diff options
Diffstat (limited to 'fs/befs')
| -rw-r--r-- | fs/befs/ChangeLog | 417 | ||||
| -rw-r--r-- | fs/befs/Kconfig | 27 | ||||
| -rw-r--r-- | fs/befs/Makefile | 8 | ||||
| -rw-r--r-- | fs/befs/befs.h | 150 | ||||
| -rw-r--r-- | fs/befs/befs_fs_types.h | 256 | ||||
| -rw-r--r-- | fs/befs/btree.c | 784 | ||||
| -rw-r--r-- | fs/befs/btree.h | 12 | ||||
| -rw-r--r-- | fs/befs/datastream.c | 525 | ||||
| -rw-r--r-- | fs/befs/datastream.h | 20 | ||||
| -rw-r--r-- | fs/befs/debug.c | 262 | ||||
| -rw-r--r-- | fs/befs/endian.h | 126 | ||||
| -rw-r--r-- | fs/befs/inode.c | 55 | ||||
| -rw-r--r-- | fs/befs/inode.h | 7 | ||||
| -rw-r--r-- | fs/befs/io.c | 61 | ||||
| -rw-r--r-- | fs/befs/io.h | 6 | ||||
| -rw-r--r-- | fs/befs/linuxvfs.c | 1027 | ||||
| -rw-r--r-- | fs/befs/super.c | 118 | ||||
| -rw-r--r-- | fs/befs/super.h | 6 |
18 files changed, 3867 insertions, 0 deletions
diff --git a/fs/befs/ChangeLog b/fs/befs/ChangeLog new file mode 100644 index 000000000..aff7eec8f --- /dev/null +++ b/fs/befs/ChangeLog @@ -0,0 +1,417 @@ +Version 0.92 (2002-03-29) +========== +* Minor cleanup. Ran Lindent on the sources. + +Version 0.92 (2002-03-27) +========== +* Fixed module makefile problem. It was not compiling all the correct + source files! +* Removed duplicated function definition +* Fixed potential null pointer dereference when reporting an error + +Version 0.91 (2002-03-26) +========== +* Oy! Fixed stupid bug that would cause an unresolved symbol error. + Thanks to Laszlo Boszormenyi for pointing this out to me. + +Version 0.9 (2002-03-14) +========== +* Added Sergey S. Kostyliov's patch to eliminate memcpy() overhead + from b+tree operations. Changes the befs_read_datastream() interface. + +* Segregated the functions that interface directly with the linux vfs + interface into their own file called linuxvfs.c. [WD] + +Version 0.64 (2002-02-07) +========== +* Did the string comparison really right this time (btree.c) [WD] + +* Fixed up some places where I assumed that a long int could hold + a pointer value. (btree.c) [WD] + +* Andrew Farnham <andrewfarnham@uq.net.au> pointed out that the module + wouldn't work on older (<2.4.10) kernels due to an unresolved symbol. + This is bad, since 2.4.9 is still the current RedHat kernel. I added + a workaround for this problem (compatibility.h) [WD] + +* Sergey S. Kostyliov made befs_find_key() use a binary search to find + keys within btree nodes, rather than the linear search we were using + before. (btree.c) [Sergey S. Kostyliov <rathamahata@php4.ru>] + +* Made a debian package of the source for use with kernel-package. [WD] + + +Version 0.63 (2002-01-31) +========== +* Fixed bug in befs_find_brun_indirect() that would result in the wrong + block being read. It was introduced when adding byteswapping in + 0.61. (datastream.c) [WD] + +* Fixed a longstanding bug in befs_find_key() that would result in it + finding the first key that is a substring of the string it is searching + for. For example, this would cause files in the same directory with + names like file1 and file2 to mysteriously be duplicates of each other + (because they have the same inode number). Many thanks to Pavel Roskin + for reporting this serious bug!!! + (btree.c) [WD] + +* Added support for long symlinks, after Axel Dorfler explained up how + they work. I had forgotten all about them. (inode.c, symlink.c) [WD] + +* Documentation improvements in source. [WD] + +* Makefile fix for independent module when CONFIG_MODVERSION is set in + kernel config [Pavel Roskin <proski@gnu.org>] + +* Compile warning fix for namei.c. [Sergey S. Kostyliov <rathamahata@php4.ru>] + + +Version 0.62 +========== +* Fixed makefile for module install [WD] + + +Version 0.61 (2002-01-20) +========== +* Made functions in endian.h to do the correct byteswapping, no matter + the arch. [WD] + +* Abbandoned silly checks for a NULL superblock pointer in debug.c. [WD] + +* Misc code cleanups. Also cleanup of this changelog file. [WD] + +* Added byteswapping to all metadata reads from disk. + Uses the functions from endian.h [WD] + +* Remove the typedef of struct super_block to vfs_sb, as it offended + certain peoples' aesthetic sense. [WD] + +* Ditto with the befs_read_block() interface. [WD] + + +Version 0.6 (2001-12-15) +========== +* Cleanup of NLS functions (util.c) [WD] + +* Make directory lookup/read use the NLS if an iocharset is provided. [WD] + +* Fixed stupid bug where specifying the uid or gid mount options as '0' + would result in the filesystem using the on-disk uid and gid. [WD] + +* Added mount option to control debug printing. + The option is, simply enough, 'debug'. + (super.c, debug.c) [WD] + +* Removed notion of btree handle from btree.c. It was unnecessary, as the + linux VFS doesn't allow us to keep any state between calls. Updated + dir.c, namei.c befs_fs.h to account for it. [WD] + +* Improved handleing of overflow nodes when listing directories. + Now works for overflow nodes hanging off of nodes other than the root + node. This is the cleaner solution to Brent Miszalaski's problem. [WD] + +* Added new debug/warning/error print functions in debug.c. + More flexible. Will soon be controllable at mount time + (see TODO). [WD] + +* Rewrote datastream position lookups. + (datastream.c) [WD] + +* Moved the TODO list to its own file. + + +Version 0.50 (2001-11-13) +========== +* Added workaround for mis-understanding of the nature of the b+trees used + in directories. A cleaner solution will come after I've thought about it + for a while. Thanks to Brent Miszalaski for finding and reporting this bug. + (btree.c) [WD] + +* Minor cleanups + +* Added test for "impossible" condition of empty internal nodes in + seekleaf() in btree.c [WD] + +* Implemented the abstracted read_block() in io.c [WD] + +* Cleaned up the inode validation in inode.c [WD] + +* Anton Altaparmakov figured out (by asking Linus :) ) what was causing the + hanging disk io problem. It turns out you need to have the sync_pages + callback defined in your address_space_ops, even if it just uses the + default linux-supplied implementation. Fixed. Works now. + (file.c) [WD] + +* Anton Altaparmakov and Christoph Hellwig alerted me to the fact that + filesystem code should be using GFP_NOFS instead of GFP_KERNEL as the + priority parameter to kmalloc(). Fixed. + (datastream.c, btree.c super.c inode.c) [WD] + +* Anton also told me that the blocksize is not allowed to be larger than + the page size in linux, which is 4k i386. Oops. Added a test for + (blocksize > PAGE_SIZE), and refuse to mount in that case. What this + practically means is that 8k blocksize volumes won't work without a major + restructuring of the driver (or an alpha or other 64bit hardware). [WD] + +* Cleaned up the befs_count_blocks() function. Much smarter now. + And somewhat smaller too. [WD] + +* Made inode allocations use a slab cache + (super.c inode.c) [WD] + +* Moved the freeing of the private inode section from put_inode() to + clear_inode(). This fixes a potential free twice type bug. Put_inode() + can be called multiple times for each inode struct. [WD] + +* Converted all non vfs-callback functions to use befs_sb_info as the + superblock type, rather than struct super_block. This is for + portablity. [WD] + +* Fixed a couple of compile warnings due to use of malloc.h, when slab.h + is the new way. (inode.c, super.c) [WD] + +* Fixed erronous includes of linux/befs_fs_i.h and linux/befs_fs_sb.h + in inode.c [WD] + +Version 0.45 (2001-10-29) +========== +* Added functions to get the private superblock and inode structures from + their enclosing public structures. Switched all references to the + private portions to use them. (many files) [WD] + +* Made read_super and read_inode allocate the private portions of those + structures into the generic pointer fields of the public structures + with kmalloc(). put_super and put_inode free them. This allows us not + to have to touch the definitions of the public structures in + include/linux/fs.h. Also, befs_inode_info is huge (because of the + symlink string). (super.c, inode.c, befs_fs.h) [WD] + +* Fixed a thinko that was corrupting file reads after the first block_run + is done being read. (datastream.c) [WD] + +* Removed fsync() hooks, since a read-only filesystem doesn't need them. + [Christoph Hellwig]. + +* Fixed befs_readlink() (symlink.c) [Christoph Hellwig]. + +* Removed all the Read-Write stuff. I'll redo it when it is time to add + write support (various files) [WD]. + +* Removed prototypes for functions who's definitions have been removed + (befs_fs.h) [WD]. + + +Version 0.4 (2001-10-28) +========== +* Made it an option to use the old non-pagecache befs_file_read() for + testing purposes. (fs/Config.in) + +* Fixed unused variable warnings when compiling without debugging. + +* Fixed a bug where the inode and super_block didn't get their blockbits + fields set (inode.c and super.c). + +* Release patch version 11. AKA befs-driver version 0.4. + +* Thats right. New versioning scheme. + I've done some serious testing on it now (on my box anyhow), and it + seems stable and not outragously slow. Existing features are more-or-less + correct (see TODO list). But it isn't 1.0 yet. I think 0.4 gives me some + headroom before the big 1.0. + + +2001-10-26 +========== +* Fixed date format in this file. Was I smoking crack? + +* Removed old datastream code from file.c, since it is nolonger used. + +* Generic_read_file() is now used to read regular file data. + It doesn't chew up the buffer cache (it does page io instead), and seems + to be about as fast (even though it has to look up each file block + indivdualy). And it knows about doing readahead, which is a major plus. + So it does i/o in much larger chunks. It is the correct linux way. It + uses befs_get_block() by way of befs_readpage() to find the disk offsets + of blocks, which in turn calls befs_fpos2brun() in datastream.c to do + the hard work of finding the disk block number. + +* Changed method of checking for a dirty filesystem in befs_read_super + (super.c). Now we check to see if log_start and log_end differ. If so, + the journal needs to be replayed, and the filesystem cannot be mounted. + +* Fixed an extra instance of MOD_DEC_USE_COUNT in super.c + +* Fixed a problem with reading the superblock on devices with large sector + sizes (such as cdroms) on linux 2.4.10 and up. + +2001-10-24 +========== +* Fix nasty bug in converting block numbers to struct befs_inode_addr. + Subtle, because the old version was only sometimes wrong. + Probably responsible for lots of problems. (inode.c) + +* Fix bug with reading an empty directory. (btree.c and dir.c) + +* This one looks good. Release patch version 10 + +2001-10-23 +========== +* Added btree searching function. + +* Use befs_btree_find in befs_lookup (namei.c) + +* Additional comments in btree.c + +2001-10-22 +========== +* Added B+tree reading functions (in btree.c). + Made befs_readdir() use them them instead of the cruft in index.c. + +2001-09-11 +========== +* Converted befs_read_file() to use the new datastream code. + +* Finally updated the README file. + +* Added many comments. + +* Posted version 6 + +* Removed byte-order conversion code. + I have no intention of supporting it, and it was very ugly. + Flow control with #ifdef (ugh). Maybe I'll redo it once + native byteorder works 100%. + +2001-09-10 +========== +* Finished implementing read_datastream() + +* made befs_read_brun() more general + Supports an offset to start at and a max bytes to read + Added a wrapper function to give the old call + +2001-09-30 +========== +* Discovered that the datastream handleing code in file.c is quite deficient + in several respects. For one thing, it doesn't deal with indirect blocks + +* Rewrote datastream handleing. + +* Created io.c, for io related functions. + Previously, the befs_bread() funtions lived in file.c + Created the befs_read_brun() function. + + +2001-09-07 +========== +* Made a function to actually count the number of fs blocks used by a file. + And helper functions. + (fs/befs/inode.c) + +2001-09-05 +========== +* Fixed a misunderstanding of the inode fields. + This fixed the problmem with wrong file sizes from du and others. + The i_blocks field of the inode struct is not the number of blocks for the + inode, it is the number of blocks for the file. Also, i_blksize is not + necessarily the size of the inode, although in practice it works out. + Changed to blocksize of filesystem. + (fs/befs/inode.c) + +* Permanently removed code that had been provisionally ifdefed out of befs_fs.h + +* Since we don't support access time, make that field zero, instead of + copying m_time. + (fs/befs/inode.c) + +* Added sanity check for inode reading + Make sure inode we got was the one we asked for. + (fs/befs/inode.c) + +* Code cleanup + Local pointers to commonly used structures in inode.c. + Got rid of abominations befs_iaddr2inode() and befs_inode2ino(). + Replaced with single function iaddr2blockno(). + (fs/befs/super.c) (fs/befs/inode.c) + +2001-09-01 +========== +* Fixed the problem with statfs where it would always claim the disk was + half full, due to improper understanding of the statfs fields. + (fs/befs/super.c) + +* Posted verion 4 of the patch + +2001-09-01 +========== +* Changed the macros in befs_fs.h to inline functions. + More readable. Typesafe. Better + (include/linux/befs_fs.h) + +* Moved type definitions from befs_fs.h to a new file, befs_fs_types.h + Because befs_fs_i.h and befs_fs_sb.h were including befs_fs.h for the + typedefs, and they are inlcuded in <linux/fs.h>, which has definitions + that I want the inline functions in befs_fs.h to be able to see. Nasty + circularity. + (include/linux/befs_fs.h) + +2001-08-30 +========== +* Cleaned up some wording. + +* Added additional consitency checks on mount + Check block_size agrees with block_shift + Check flags == BEFS_CLEAN + (fs/befs/super.c) + +* Tell the kernel to only mount befs read-only. + By setting the SB_RDONLY flag in befs_read_super(). + Not that it was possible to write before. But now the kernel won't even try. + (fs/befs/super.c) + +* Got rid of kernel warning on mount. + The kernel doesn't like it if you call set_blocksize() on a device when + you have some of its blocks open. Moved the second set_blocksize() to the + very end of befs_read_super(), after we are done with the disk superblock. + (fs/befs/super.c) + +* Fixed wrong number of args bug in befs_dump_inode + (fs/befs/debug.c) + +* Solved lots of type mismatches in kprint()s + (everwhere) + +2001-08-27 +========== +* Cleaned up the fs/Config.in entries a bit, now slightly more descriptive. + +* BeFS depends on NLS, so I made activating BeFS enable the NLS questions + (fs/nls/Config.in) + +* Added Configure.help entries for CONFIG_BEFS_FS and CONFIG_DEBUG_BEFS + (currently at fs/befs/Kconfig) + +2001-08-?? +========== +* Removed superblock locking calls in befs_read_super(). In 2.4, the VFS + hands us a super_block struct that is already locked. + +2001-08-13 +========== +* Will Dyson <will_dyson@pobox.com> is now attempting to maintain this module + Makoto Kato <m_kato@ga2.so-net.ne.jp> is original author.Daniel Berlin + also did some work on it (fixing it up for the later 2.3.x kernels, IIRC). + +* Fixed compile errors on 2.4.1 kernel (WD) + Resolve rejected patches + Accommodate changed NLS interface (util.h) + Needed to include <linux/slab.h> in most files + Makefile changes + fs/Config.in changes + +* Tried to niceify the code using the ext2 fs as a guide + Declare befs_fs_type using the DECLARE_FSTYPE_DEV() macro + +* Made it a configure option to turn on debugging (fs/Config.in) + +* Compiles on 2.4.7 diff --git a/fs/befs/Kconfig b/fs/befs/Kconfig new file mode 100644 index 000000000..9550b6462 --- /dev/null +++ b/fs/befs/Kconfig @@ -0,0 +1,27 @@ +# SPDX-License-Identifier: GPL-2.0-only +config BEFS_FS + tristate "BeOS file system (BeFS) support (read only)" + depends on BLOCK + select NLS + help + The BeOS File System (BeFS) is the native file system of Be, Inc's + BeOS. Notable features include support for arbitrary attributes + on files and directories, and database-like indices on selected + attributes. (Also note that this driver doesn't make those features + available at this time). It is a 64 bit filesystem, so it supports + extremely large volumes and files. + + If you use this filesystem, you should also say Y to at least one + of the NLS (native language support) options below. + + If you don't know what this is about, say N. + + To compile this as a module, choose M here: the module will be + called befs. + +config BEFS_DEBUG + bool "Debug BeFS" + depends on BEFS_FS + help + If you say Y here, you can use the 'debug' mount option to enable + debugging output from the driver. diff --git a/fs/befs/Makefile b/fs/befs/Makefile new file mode 100644 index 000000000..6c9c3cbc5 --- /dev/null +++ b/fs/befs/Makefile @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the linux BeOS filesystem routines. +# + +obj-$(CONFIG_BEFS_FS) += befs.o +ccflags-$(CONFIG_BEFS_DEBUG) += -DDEBUG +befs-objs := datastream.o btree.o super.o inode.o debug.o io.o linuxvfs.o diff --git a/fs/befs/befs.h b/fs/befs/befs.h new file mode 100644 index 000000000..7cd472456 --- /dev/null +++ b/fs/befs/befs.h @@ -0,0 +1,150 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * befs.h + * + * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com> + * Copyright (C) 1999 Makoto Kato (m_kato@ga2.so-net.ne.jp) + */ + +#ifndef _LINUX_BEFS_H +#define _LINUX_BEFS_H + +#include "befs_fs_types.h" + +/* used in debug.c */ +#define BEFS_VERSION "0.9.3" + + +typedef u64 befs_blocknr_t; +/* + * BeFS in memory structures + */ + +struct befs_mount_options { + kgid_t gid; + kuid_t uid; + int use_gid; + int use_uid; + int debug; + char *iocharset; +}; + +struct befs_sb_info { + u32 magic1; + u32 block_size; + u32 block_shift; + int byte_order; + befs_off_t num_blocks; + befs_off_t used_blocks; + u32 inode_size; + u32 magic2; + + /* Allocation group information */ + u32 blocks_per_ag; + u32 ag_shift; + u32 num_ags; + + /* State of the superblock */ + u32 flags; + + /* Journal log entry */ + befs_block_run log_blocks; + befs_off_t log_start; + befs_off_t log_end; + + befs_inode_addr root_dir; + befs_inode_addr indices; + u32 magic3; + + struct befs_mount_options mount_opts; + struct nls_table *nls; +}; + +struct befs_inode_info { + u32 i_flags; + u32 i_type; + + befs_inode_addr i_inode_num; + befs_inode_addr i_parent; + befs_inode_addr i_attribute; + + union { + befs_data_stream ds; + char symlink[BEFS_SYMLINK_LEN]; + } i_data; + + struct inode vfs_inode; +}; + +enum befs_err { + BEFS_OK, + BEFS_ERR, + BEFS_BAD_INODE, + BEFS_BT_END, + BEFS_BT_EMPTY, + BEFS_BT_MATCH, + BEFS_BT_OVERFLOW, + BEFS_BT_NOT_FOUND +}; + + +/****************************/ +/* debug.c */ +__printf(2, 3) +void befs_error(const struct super_block *sb, const char *fmt, ...); +__printf(2, 3) +void befs_warning(const struct super_block *sb, const char *fmt, ...); +__printf(2, 3) +void befs_debug(const struct super_block *sb, const char *fmt, ...); + +void befs_dump_super_block(const struct super_block *sb, befs_super_block *); +void befs_dump_inode(const struct super_block *sb, befs_inode *); +void befs_dump_index_entry(const struct super_block *sb, befs_disk_btree_super *); +void befs_dump_index_node(const struct super_block *sb, befs_btree_nodehead *); +/****************************/ + + +/* Gets a pointer to the private portion of the super_block + * structure from the public part + */ +static inline struct befs_sb_info * +BEFS_SB(const struct super_block *super) +{ + return (struct befs_sb_info *) super->s_fs_info; +} + +static inline struct befs_inode_info * +BEFS_I(const struct inode *inode) +{ + return container_of(inode, struct befs_inode_info, vfs_inode); +} + +static inline befs_blocknr_t +iaddr2blockno(struct super_block *sb, const befs_inode_addr *iaddr) +{ + return ((iaddr->allocation_group << BEFS_SB(sb)->ag_shift) + + iaddr->start); +} + +static inline befs_inode_addr +blockno2iaddr(struct super_block *sb, befs_blocknr_t blockno) +{ + befs_inode_addr iaddr; + + iaddr.allocation_group = blockno >> BEFS_SB(sb)->ag_shift; + iaddr.start = + blockno - (iaddr.allocation_group << BEFS_SB(sb)->ag_shift); + iaddr.len = 1; + + return iaddr; +} + +static inline unsigned int +befs_iaddrs_per_block(struct super_block *sb) +{ + return BEFS_SB(sb)->block_size / sizeof(befs_disk_inode_addr); +} + +#include "endian.h" + +#endif /* _LINUX_BEFS_H */ diff --git a/fs/befs/befs_fs_types.h b/fs/befs/befs_fs_types.h new file mode 100644 index 000000000..8019fde81 --- /dev/null +++ b/fs/befs/befs_fs_types.h @@ -0,0 +1,256 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * fs/befs/befs_fs_types.h + * + * Copyright (C) 2001 Will Dyson (will@cs.earlham.edu) + * + * + * + * from linux/include/linux/befs_fs.h + * + * Copyright (C) 1999 Makoto Kato (m_kato@ga2.so-net.ne.jp) + * + */ + +#ifndef _LINUX_BEFS_FS_TYPES +#define _LINUX_BEFS_FS_TYPES + +#ifdef __KERNEL__ +#include <linux/types.h> +#endif /*__KERNEL__*/ + +#define PACKED __attribute__ ((__packed__)) + +/* + * Max name lengths of BFS + */ + +#define BEFS_NAME_LEN 255 + +#define BEFS_SYMLINK_LEN 144 +#define BEFS_NUM_DIRECT_BLOCKS 12 +#define B_OS_NAME_LENGTH 32 + +/* The datastream blocks mapped by the double-indirect + * block are always 4 fs blocks long. + * This eliminates the need for linear searches among + * the potentially huge number of indirect blocks + * + * Err. Should that be 4 fs blocks or 4k??? + * It matters on large blocksize volumes + */ +#define BEFS_DBLINDIR_BRUN_LEN 4 + +/* + * Flags of superblock + */ + +enum super_flags { + BEFS_BYTESEX_BE, + BEFS_BYTESEX_LE, + BEFS_CLEAN = 0x434c454e, + BEFS_DIRTY = 0x44495254, + BEFS_SUPER_MAGIC1 = 0x42465331, /* BFS1 */ + BEFS_SUPER_MAGIC2 = 0xdd121031, + BEFS_SUPER_MAGIC3 = 0x15b6830e, +}; + +#define BEFS_BYTEORDER_NATIVE 0x42494745 +#define BEFS_BYTEORDER_NATIVE_LE ((__force fs32)cpu_to_le32(BEFS_BYTEORDER_NATIVE)) +#define BEFS_BYTEORDER_NATIVE_BE ((__force fs32)cpu_to_be32(BEFS_BYTEORDER_NATIVE)) + +#define BEFS_SUPER_MAGIC BEFS_SUPER_MAGIC1 +#define BEFS_SUPER_MAGIC1_LE ((__force fs32)cpu_to_le32(BEFS_SUPER_MAGIC1)) +#define BEFS_SUPER_MAGIC1_BE ((__force fs32)cpu_to_be32(BEFS_SUPER_MAGIC1)) + +/* + * Flags of inode + */ + +#define BEFS_INODE_MAGIC1 0x3bbe0ad9 + +enum inode_flags { + BEFS_INODE_IN_USE = 0x00000001, + BEFS_ATTR_INODE = 0x00000004, + BEFS_INODE_LOGGED = 0x00000008, + BEFS_INODE_DELETED = 0x00000010, + BEFS_LONG_SYMLINK = 0x00000040, + BEFS_PERMANENT_FLAG = 0x0000ffff, + BEFS_INODE_NO_CREATE = 0x00010000, + BEFS_INODE_WAS_WRITTEN = 0x00020000, + BEFS_NO_TRANSACTION = 0x00040000, +}; +/* + * On-Disk datastructures of BeFS + */ + +typedef u64 __bitwise fs64; +typedef u32 __bitwise fs32; +typedef u16 __bitwise fs16; + +typedef u64 befs_off_t; +typedef fs64 befs_time_t; + +/* Block runs */ +typedef struct { + fs32 allocation_group; + fs16 start; + fs16 len; +} PACKED befs_disk_block_run; + +typedef struct { + u32 allocation_group; + u16 start; + u16 len; +} PACKED befs_block_run; + +typedef befs_disk_block_run befs_disk_inode_addr; +typedef befs_block_run befs_inode_addr; + +/* + * The Superblock Structure + */ +typedef struct { + char name[B_OS_NAME_LENGTH]; + fs32 magic1; + fs32 fs_byte_order; + + fs32 block_size; + fs32 block_shift; + + fs64 num_blocks; + fs64 used_blocks; + + fs32 inode_size; + + fs32 magic2; + fs32 blocks_per_ag; + fs32 ag_shift; + fs32 num_ags; + + fs32 flags; + + befs_disk_block_run log_blocks; + fs64 log_start; + fs64 log_end; + + fs32 magic3; + befs_disk_inode_addr root_dir; + befs_disk_inode_addr indices; + +} PACKED befs_super_block; + +/* + * Note: the indirect and dbl_indir block_runs may + * be longer than one block! + */ +typedef struct { + befs_disk_block_run direct[BEFS_NUM_DIRECT_BLOCKS]; + fs64 max_direct_range; + befs_disk_block_run indirect; + fs64 max_indirect_range; + befs_disk_block_run double_indirect; + fs64 max_double_indirect_range; + fs64 size; +} PACKED befs_disk_data_stream; + +typedef struct { + befs_block_run direct[BEFS_NUM_DIRECT_BLOCKS]; + befs_off_t max_direct_range; + befs_block_run indirect; + befs_off_t max_indirect_range; + befs_block_run double_indirect; + befs_off_t max_double_indirect_range; + befs_off_t size; +} PACKED befs_data_stream; + +/* Attribute */ +typedef struct { + fs32 type; + fs16 name_size; + fs16 data_size; + char name[1]; +} PACKED befs_small_data; + +/* Inode structure */ +typedef struct { + fs32 magic1; + befs_disk_inode_addr inode_num; + fs32 uid; + fs32 gid; + fs32 mode; + fs32 flags; + befs_time_t create_time; + befs_time_t last_modified_time; + befs_disk_inode_addr parent; + befs_disk_inode_addr attributes; + fs32 type; + + fs32 inode_size; + fs32 etc; /* not use */ + + union { + befs_disk_data_stream datastream; + char symlink[BEFS_SYMLINK_LEN]; + } data; + + fs32 pad[4]; /* not use */ + befs_small_data small_data[1]; +} PACKED befs_inode; + +/* + * B+tree superblock + */ + +#define BEFS_BTREE_MAGIC 0x69f6c2e8 + +enum btree_types { + BTREE_STRING_TYPE = 0, + BTREE_INT32_TYPE = 1, + BTREE_UINT32_TYPE = 2, + BTREE_INT64_TYPE = 3, + BTREE_UINT64_TYPE = 4, + BTREE_FLOAT_TYPE = 5, + BTREE_DOUBLE_TYPE = 6 +}; + +typedef struct { + fs32 magic; + fs32 node_size; + fs32 max_depth; + fs32 data_type; + fs64 root_node_ptr; + fs64 free_node_ptr; + fs64 max_size; +} PACKED befs_disk_btree_super; + +typedef struct { + u32 magic; + u32 node_size; + u32 max_depth; + u32 data_type; + befs_off_t root_node_ptr; + befs_off_t free_node_ptr; + befs_off_t max_size; +} PACKED befs_btree_super; + +/* + * Header structure of each btree node + */ +typedef struct { + fs64 left; + fs64 right; + fs64 overflow; + fs16 all_key_count; + fs16 all_key_length; +} PACKED befs_btree_nodehead; + +typedef struct { + befs_off_t left; + befs_off_t right; + befs_off_t overflow; + u16 all_key_count; + u16 all_key_length; +} PACKED befs_host_btree_nodehead; + +#endif /* _LINUX_BEFS_FS_TYPES */ diff --git a/fs/befs/btree.c b/fs/befs/btree.c new file mode 100644 index 000000000..1b7e0f712 --- /dev/null +++ b/fs/befs/btree.c @@ -0,0 +1,784 @@ +/* + * linux/fs/befs/btree.c + * + * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com> + * + * Licensed under the GNU GPL. See the file COPYING for details. + * + * 2002-02-05: Sergey S. Kostyliov added binary search within + * btree nodes. + * + * Many thanks to: + * + * Dominic Giampaolo, author of "Practical File System + * Design with the Be File System", for such a helpful book. + * + * Marcus J. Ranum, author of the b+tree package in + * comp.sources.misc volume 10. This code is not copied from that + * work, but it is partially based on it. + * + * Makoto Kato, author of the original BeFS for linux filesystem + * driver. + */ + +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/buffer_head.h> + +#include "befs.h" +#include "btree.h" +#include "datastream.h" + +/* + * The btree functions in this file are built on top of the + * datastream.c interface, which is in turn built on top of the + * io.c interface. + */ + +/* Befs B+tree structure: + * + * The first thing in the tree is the tree superblock. It tells you + * all kinds of useful things about the tree, like where the rootnode + * is located, and the size of the nodes (always 1024 with current version + * of BeOS). + * + * The rest of the tree consists of a series of nodes. Nodes contain a header + * (struct befs_btree_nodehead), the packed key data, an array of shorts + * containing the ending offsets for each of the keys, and an array of + * befs_off_t values. In interior nodes, the keys are the ending keys for + * the childnode they point to, and the values are offsets into the + * datastream containing the tree. + */ + +/* Note: + * + * The book states 2 confusing things about befs b+trees. First, + * it states that the overflow field of node headers is used by internal nodes + * to point to another node that "effectively continues this one". Here is what + * I believe that means. Each key in internal nodes points to another node that + * contains key values less than itself. Inspection reveals that the last key + * in the internal node is not the last key in the index. Keys that are + * greater than the last key in the internal node go into the overflow node. + * I imagine there is a performance reason for this. + * + * Second, it states that the header of a btree node is sufficient to + * distinguish internal nodes from leaf nodes. Without saying exactly how. + * After figuring out the first, it becomes obvious that internal nodes have + * overflow nodes and leafnodes do not. + */ + +/* + * Currently, this code is only good for directory B+trees. + * In order to be used for other BFS indexes, it needs to be extended to handle + * duplicate keys and non-string keytypes (int32, int64, float, double). + */ + +/* + * In memory structure of each btree node + */ +struct befs_btree_node { + befs_host_btree_nodehead head; /* head of node converted to cpu byteorder */ + struct buffer_head *bh; + befs_btree_nodehead *od_node; /* on disk node */ +}; + +/* local constants */ +static const befs_off_t BEFS_BT_INVAL = 0xffffffffffffffffULL; + +/* local functions */ +static int befs_btree_seekleaf(struct super_block *sb, const befs_data_stream *ds, + befs_btree_super * bt_super, + struct befs_btree_node *this_node, + befs_off_t * node_off); + +static int befs_bt_read_super(struct super_block *sb, const befs_data_stream *ds, + befs_btree_super * sup); + +static int befs_bt_read_node(struct super_block *sb, const befs_data_stream *ds, + struct befs_btree_node *node, + befs_off_t node_off); + +static int befs_leafnode(struct befs_btree_node *node); + +static fs16 *befs_bt_keylen_index(struct befs_btree_node *node); + +static fs64 *befs_bt_valarray(struct befs_btree_node *node); + +static char *befs_bt_keydata(struct befs_btree_node *node); + +static int befs_find_key(struct super_block *sb, + struct befs_btree_node *node, + const char *findkey, befs_off_t * value); + +static char *befs_bt_get_key(struct super_block *sb, + struct befs_btree_node *node, + int index, u16 * keylen); + +static int befs_compare_strings(const void *key1, int keylen1, + const void *key2, int keylen2); + +/** + * befs_bt_read_super() - read in btree superblock convert to cpu byteorder + * @sb: Filesystem superblock + * @ds: Datastream to read from + * @sup: Buffer in which to place the btree superblock + * + * Calls befs_read_datastream to read in the btree superblock and + * makes sure it is in cpu byteorder, byteswapping if necessary. + * Return: BEFS_OK on success and if *@sup contains the btree superblock in cpu + * byte order. Otherwise return BEFS_ERR on error. + */ +static int +befs_bt_read_super(struct super_block *sb, const befs_data_stream *ds, + befs_btree_super * sup) +{ + struct buffer_head *bh; + befs_disk_btree_super *od_sup; + + befs_debug(sb, "---> %s", __func__); + + bh = befs_read_datastream(sb, ds, 0, NULL); + + if (!bh) { + befs_error(sb, "Couldn't read index header."); + goto error; + } + od_sup = (befs_disk_btree_super *) bh->b_data; + befs_dump_index_entry(sb, od_sup); + + sup->magic = fs32_to_cpu(sb, od_sup->magic); + sup->node_size = fs32_to_cpu(sb, od_sup->node_size); + sup->max_depth = fs32_to_cpu(sb, od_sup->max_depth); + sup->data_type = fs32_to_cpu(sb, od_sup->data_type); + sup->root_node_ptr = fs64_to_cpu(sb, od_sup->root_node_ptr); + + brelse(bh); + if (sup->magic != BEFS_BTREE_MAGIC) { + befs_error(sb, "Index header has bad magic."); + goto error; + } + + befs_debug(sb, "<--- %s", __func__); + return BEFS_OK; + + error: + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_bt_read_node - read in btree node and convert to cpu byteorder + * @sb: Filesystem superblock + * @ds: Datastream to read from + * @node: Buffer in which to place the btree node + * @node_off: Starting offset (in bytes) of the node in @ds + * + * Calls befs_read_datastream to read in the indicated btree node and + * makes sure its header fields are in cpu byteorder, byteswapping if + * necessary. + * Note: node->bh must be NULL when this function is called the first time. + * Don't forget brelse(node->bh) after last call. + * + * On success, returns BEFS_OK and *@node contains the btree node that + * starts at @node_off, with the node->head fields in cpu byte order. + * + * On failure, BEFS_ERR is returned. + */ + +static int +befs_bt_read_node(struct super_block *sb, const befs_data_stream *ds, + struct befs_btree_node *node, befs_off_t node_off) +{ + uint off = 0; + + befs_debug(sb, "---> %s", __func__); + + if (node->bh) + brelse(node->bh); + + node->bh = befs_read_datastream(sb, ds, node_off, &off); + if (!node->bh) { + befs_error(sb, "%s failed to read " + "node at %llu", __func__, node_off); + befs_debug(sb, "<--- %s ERROR", __func__); + + return BEFS_ERR; + } + node->od_node = + (befs_btree_nodehead *) ((void *) node->bh->b_data + off); + + befs_dump_index_node(sb, node->od_node); + + node->head.left = fs64_to_cpu(sb, node->od_node->left); + node->head.right = fs64_to_cpu(sb, node->od_node->right); + node->head.overflow = fs64_to_cpu(sb, node->od_node->overflow); + node->head.all_key_count = + fs16_to_cpu(sb, node->od_node->all_key_count); + node->head.all_key_length = + fs16_to_cpu(sb, node->od_node->all_key_length); + + befs_debug(sb, "<--- %s", __func__); + return BEFS_OK; +} + +/** + * befs_btree_find - Find a key in a befs B+tree + * @sb: Filesystem superblock + * @ds: Datastream containing btree + * @key: Key string to lookup in btree + * @value: Value stored with @key + * + * On success, returns BEFS_OK and sets *@value to the value stored + * with @key (usually the disk block number of an inode). + * + * On failure, returns BEFS_ERR or BEFS_BT_NOT_FOUND. + * + * Algorithm: + * Read the superblock and rootnode of the b+tree. + * Drill down through the interior nodes using befs_find_key(). + * Once at the correct leaf node, use befs_find_key() again to get the + * actual value stored with the key. + */ +int +befs_btree_find(struct super_block *sb, const befs_data_stream *ds, + const char *key, befs_off_t * value) +{ + struct befs_btree_node *this_node; + befs_btree_super bt_super; + befs_off_t node_off; + int res; + + befs_debug(sb, "---> %s Key: %s", __func__, key); + + if (befs_bt_read_super(sb, ds, &bt_super) != BEFS_OK) { + befs_error(sb, + "befs_btree_find() failed to read index superblock"); + goto error; + } + + this_node = kmalloc(sizeof(struct befs_btree_node), + GFP_NOFS); + if (!this_node) { + befs_error(sb, "befs_btree_find() failed to allocate %zu " + "bytes of memory", sizeof(struct befs_btree_node)); + goto error; + } + + this_node->bh = NULL; + + /* read in root node */ + node_off = bt_super.root_node_ptr; + if (befs_bt_read_node(sb, ds, this_node, node_off) != BEFS_OK) { + befs_error(sb, "befs_btree_find() failed to read " + "node at %llu", node_off); + goto error_alloc; + } + + while (!befs_leafnode(this_node)) { + res = befs_find_key(sb, this_node, key, &node_off); + /* if no key set, try the overflow node */ + if (res == BEFS_BT_OVERFLOW) + node_off = this_node->head.overflow; + if (befs_bt_read_node(sb, ds, this_node, node_off) != BEFS_OK) { + befs_error(sb, "befs_btree_find() failed to read " + "node at %llu", node_off); + goto error_alloc; + } + } + + /* at a leaf node now, check if it is correct */ + res = befs_find_key(sb, this_node, key, value); + + brelse(this_node->bh); + kfree(this_node); + + if (res != BEFS_BT_MATCH) { + befs_error(sb, "<--- %s Key %s not found", __func__, key); + befs_debug(sb, "<--- %s ERROR", __func__); + *value = 0; + return BEFS_BT_NOT_FOUND; + } + befs_debug(sb, "<--- %s Found key %s, value %llu", __func__, + key, *value); + return BEFS_OK; + + error_alloc: + kfree(this_node); + error: + *value = 0; + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_find_key - Search for a key within a node + * @sb: Filesystem superblock + * @node: Node to find the key within + * @findkey: Keystring to search for + * @value: If key is found, the value stored with the key is put here + * + * Finds exact match if one exists, and returns BEFS_BT_MATCH. + * If there is no match and node's value array is too small for key, return + * BEFS_BT_OVERFLOW. + * If no match and node should countain this key, return BEFS_BT_NOT_FOUND. + * + * Uses binary search instead of a linear. + */ +static int +befs_find_key(struct super_block *sb, struct befs_btree_node *node, + const char *findkey, befs_off_t * value) +{ + int first, last, mid; + int eq; + u16 keylen; + int findkey_len; + char *thiskey; + fs64 *valarray; + + befs_debug(sb, "---> %s %s", __func__, findkey); + + findkey_len = strlen(findkey); + + /* if node can not contain key, just skip this node */ + last = node->head.all_key_count - 1; + thiskey = befs_bt_get_key(sb, node, last, &keylen); + + eq = befs_compare_strings(thiskey, keylen, findkey, findkey_len); + if (eq < 0) { + befs_debug(sb, "<--- node can't contain %s", findkey); + return BEFS_BT_OVERFLOW; + } + + valarray = befs_bt_valarray(node); + + /* simple binary search */ + first = 0; + mid = 0; + while (last >= first) { + mid = (last + first) / 2; + befs_debug(sb, "first: %d, last: %d, mid: %d", first, last, + mid); + thiskey = befs_bt_get_key(sb, node, mid, &keylen); + eq = befs_compare_strings(thiskey, keylen, findkey, + findkey_len); + + if (eq == 0) { + befs_debug(sb, "<--- %s found %s at %d", + __func__, thiskey, mid); + + *value = fs64_to_cpu(sb, valarray[mid]); + return BEFS_BT_MATCH; + } + if (eq > 0) + last = mid - 1; + else + first = mid + 1; + } + + /* return an existing value so caller can arrive to a leaf node */ + if (eq < 0) + *value = fs64_to_cpu(sb, valarray[mid + 1]); + else + *value = fs64_to_cpu(sb, valarray[mid]); + befs_error(sb, "<--- %s %s not found", __func__, findkey); + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_BT_NOT_FOUND; +} + +/** + * befs_btree_read - Traverse leafnodes of a btree + * @sb: Filesystem superblock + * @ds: Datastream containing btree + * @key_no: Key number (alphabetical order) of key to read + * @bufsize: Size of the buffer to return key in + * @keybuf: Pointer to a buffer to put the key in + * @keysize: Length of the returned key + * @value: Value stored with the returned key + * + * Here's how it works: Key_no is the index of the key/value pair to + * return in keybuf/value. + * Bufsize is the size of keybuf (BEFS_NAME_LEN+1 is a good size). Keysize is + * the number of characters in the key (just a convenience). + * + * Algorithm: + * Get the first leafnode of the tree. See if the requested key is in that + * node. If not, follow the node->right link to the next leafnode. Repeat + * until the (key_no)th key is found or the tree is out of keys. + */ +int +befs_btree_read(struct super_block *sb, const befs_data_stream *ds, + loff_t key_no, size_t bufsize, char *keybuf, size_t * keysize, + befs_off_t * value) +{ + struct befs_btree_node *this_node; + befs_btree_super bt_super; + befs_off_t node_off; + int cur_key; + fs64 *valarray; + char *keystart; + u16 keylen; + int res; + + uint key_sum = 0; + + befs_debug(sb, "---> %s", __func__); + + if (befs_bt_read_super(sb, ds, &bt_super) != BEFS_OK) { + befs_error(sb, + "befs_btree_read() failed to read index superblock"); + goto error; + } + + this_node = kmalloc(sizeof(struct befs_btree_node), GFP_NOFS); + if (this_node == NULL) { + befs_error(sb, "befs_btree_read() failed to allocate %zu " + "bytes of memory", sizeof(struct befs_btree_node)); + goto error; + } + + node_off = bt_super.root_node_ptr; + this_node->bh = NULL; + + /* seeks down to first leafnode, reads it into this_node */ + res = befs_btree_seekleaf(sb, ds, &bt_super, this_node, &node_off); + if (res == BEFS_BT_EMPTY) { + brelse(this_node->bh); + kfree(this_node); + *value = 0; + *keysize = 0; + befs_debug(sb, "<--- %s Tree is EMPTY", __func__); + return BEFS_BT_EMPTY; + } else if (res == BEFS_ERR) { + goto error_alloc; + } + + /* find the leaf node containing the key_no key */ + + while (key_sum + this_node->head.all_key_count <= key_no) { + + /* no more nodes to look in: key_no is too large */ + if (this_node->head.right == BEFS_BT_INVAL) { + *keysize = 0; + *value = 0; + befs_debug(sb, + "<--- %s END of keys at %llu", __func__, + (unsigned long long) + key_sum + this_node->head.all_key_count); + brelse(this_node->bh); + kfree(this_node); + return BEFS_BT_END; + } + + key_sum += this_node->head.all_key_count; + node_off = this_node->head.right; + + if (befs_bt_read_node(sb, ds, this_node, node_off) != BEFS_OK) { + befs_error(sb, "%s failed to read node at %llu", + __func__, (unsigned long long)node_off); + goto error_alloc; + } + } + + /* how many keys into this_node is key_no */ + cur_key = key_no - key_sum; + + /* get pointers to datastructures within the node body */ + valarray = befs_bt_valarray(this_node); + + keystart = befs_bt_get_key(sb, this_node, cur_key, &keylen); + + befs_debug(sb, "Read [%llu,%d]: keysize %d", + (long long unsigned int)node_off, (int)cur_key, + (int)keylen); + + if (bufsize < keylen + 1) { + befs_error(sb, "%s keybuf too small (%zu) " + "for key of size %d", __func__, bufsize, keylen); + brelse(this_node->bh); + goto error_alloc; + } + + strlcpy(keybuf, keystart, keylen + 1); + *value = fs64_to_cpu(sb, valarray[cur_key]); + *keysize = keylen; + + befs_debug(sb, "Read [%llu,%d]: Key \"%.*s\", Value %llu", node_off, + cur_key, keylen, keybuf, *value); + + brelse(this_node->bh); + kfree(this_node); + + befs_debug(sb, "<--- %s", __func__); + + return BEFS_OK; + + error_alloc: + kfree(this_node); + + error: + *keysize = 0; + *value = 0; + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_btree_seekleaf - Find the first leafnode in the btree + * @sb: Filesystem superblock + * @ds: Datastream containing btree + * @bt_super: Pointer to the superblock of the btree + * @this_node: Buffer to return the leafnode in + * @node_off: Pointer to offset of current node within datastream. Modified + * by the function. + * + * Helper function for btree traverse. Moves the current position to the + * start of the first leaf node. + * + * Also checks for an empty tree. If there are no keys, returns BEFS_BT_EMPTY. + */ +static int +befs_btree_seekleaf(struct super_block *sb, const befs_data_stream *ds, + befs_btree_super *bt_super, + struct befs_btree_node *this_node, + befs_off_t * node_off) +{ + + befs_debug(sb, "---> %s", __func__); + + if (befs_bt_read_node(sb, ds, this_node, *node_off) != BEFS_OK) { + befs_error(sb, "%s failed to read " + "node at %llu", __func__, *node_off); + goto error; + } + befs_debug(sb, "Seekleaf to root node %llu", *node_off); + + if (this_node->head.all_key_count == 0 && befs_leafnode(this_node)) { + befs_debug(sb, "<--- %s Tree is EMPTY", __func__); + return BEFS_BT_EMPTY; + } + + while (!befs_leafnode(this_node)) { + + if (this_node->head.all_key_count == 0) { + befs_debug(sb, "%s encountered " + "an empty interior node: %llu. Using Overflow " + "node: %llu", __func__, *node_off, + this_node->head.overflow); + *node_off = this_node->head.overflow; + } else { + fs64 *valarray = befs_bt_valarray(this_node); + *node_off = fs64_to_cpu(sb, valarray[0]); + } + if (befs_bt_read_node(sb, ds, this_node, *node_off) != BEFS_OK) { + befs_error(sb, "%s failed to read " + "node at %llu", __func__, *node_off); + goto error; + } + + befs_debug(sb, "Seekleaf to child node %llu", *node_off); + } + befs_debug(sb, "Node %llu is a leaf node", *node_off); + + return BEFS_OK; + + error: + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_leafnode - Determine if the btree node is a leaf node or an + * interior node + * @node: Pointer to node structure to test + * + * Return 1 if leaf, 0 if interior + */ +static int +befs_leafnode(struct befs_btree_node *node) +{ + /* all interior nodes (and only interior nodes) have an overflow node */ + if (node->head.overflow == BEFS_BT_INVAL) + return 1; + else + return 0; +} + +/** + * befs_bt_keylen_index - Finds start of keylen index in a node + * @node: Pointer to the node structure to find the keylen index within + * + * Returns a pointer to the start of the key length index array + * of the B+tree node *@node + * + * "The length of all the keys in the node is added to the size of the + * header and then rounded up to a multiple of four to get the beginning + * of the key length index" (p.88, practical filesystem design). + * + * Except that rounding up to 8 works, and rounding up to 4 doesn't. + */ +static fs16 * +befs_bt_keylen_index(struct befs_btree_node *node) +{ + const int keylen_align = 8; + unsigned long int off = + (sizeof (befs_btree_nodehead) + node->head.all_key_length); + ulong tmp = off % keylen_align; + + if (tmp) + off += keylen_align - tmp; + + return (fs16 *) ((void *) node->od_node + off); +} + +/** + * befs_bt_valarray - Finds the start of value array in a node + * @node: Pointer to the node structure to find the value array within + * + * Returns a pointer to the start of the value array + * of the node pointed to by the node header + */ +static fs64 * +befs_bt_valarray(struct befs_btree_node *node) +{ + void *keylen_index_start = (void *) befs_bt_keylen_index(node); + size_t keylen_index_size = node->head.all_key_count * sizeof (fs16); + + return (fs64 *) (keylen_index_start + keylen_index_size); +} + +/** + * befs_bt_keydata - Finds start of keydata array in a node + * @node: Pointer to the node structure to find the keydata array within + * + * Returns a pointer to the start of the keydata array + * of the node pointed to by the node header + */ +static char * +befs_bt_keydata(struct befs_btree_node *node) +{ + return (char *) ((void *) node->od_node + sizeof (befs_btree_nodehead)); +} + +/** + * befs_bt_get_key - returns a pointer to the start of a key + * @sb: filesystem superblock + * @node: node in which to look for the key + * @index: the index of the key to get + * @keylen: modified to be the length of the key at @index + * + * Returns a valid pointer into @node on success. + * Returns NULL on failure (bad input) and sets *@keylen = 0 + */ +static char * +befs_bt_get_key(struct super_block *sb, struct befs_btree_node *node, + int index, u16 * keylen) +{ + int prev_key_end; + char *keystart; + fs16 *keylen_index; + + if (index < 0 || index > node->head.all_key_count) { + *keylen = 0; + return NULL; + } + + keystart = befs_bt_keydata(node); + keylen_index = befs_bt_keylen_index(node); + + if (index == 0) + prev_key_end = 0; + else + prev_key_end = fs16_to_cpu(sb, keylen_index[index - 1]); + + *keylen = fs16_to_cpu(sb, keylen_index[index]) - prev_key_end; + + return keystart + prev_key_end; +} + +/** + * befs_compare_strings - compare two strings + * @key1: pointer to the first key to be compared + * @keylen1: length in bytes of key1 + * @key2: pointer to the second key to be compared + * @keylen2: length in bytes of key2 + * + * Returns 0 if @key1 and @key2 are equal. + * Returns >0 if @key1 is greater. + * Returns <0 if @key2 is greater. + */ +static int +befs_compare_strings(const void *key1, int keylen1, + const void *key2, int keylen2) +{ + int len = min_t(int, keylen1, keylen2); + int result = strncmp(key1, key2, len); + if (result == 0) + result = keylen1 - keylen2; + return result; +} + +/* These will be used for non-string keyed btrees */ +#if 0 +static int +btree_compare_int32(cont void *key1, int keylen1, const void *key2, int keylen2) +{ + return *(int32_t *) key1 - *(int32_t *) key2; +} + +static int +btree_compare_uint32(cont void *key1, int keylen1, + const void *key2, int keylen2) +{ + if (*(u_int32_t *) key1 == *(u_int32_t *) key2) + return 0; + else if (*(u_int32_t *) key1 > *(u_int32_t *) key2) + return 1; + + return -1; +} +static int +btree_compare_int64(cont void *key1, int keylen1, const void *key2, int keylen2) +{ + if (*(int64_t *) key1 == *(int64_t *) key2) + return 0; + else if (*(int64_t *) key1 > *(int64_t *) key2) + return 1; + + return -1; +} + +static int +btree_compare_uint64(cont void *key1, int keylen1, + const void *key2, int keylen2) +{ + if (*(u_int64_t *) key1 == *(u_int64_t *) key2) + return 0; + else if (*(u_int64_t *) key1 > *(u_int64_t *) key2) + return 1; + + return -1; +} + +static int +btree_compare_float(cont void *key1, int keylen1, const void *key2, int keylen2) +{ + float result = *(float *) key1 - *(float *) key2; + if (result == 0.0f) + return 0; + + return (result < 0.0f) ? -1 : 1; +} + +static int +btree_compare_double(cont void *key1, int keylen1, + const void *key2, int keylen2) +{ + double result = *(double *) key1 - *(double *) key2; + if (result == 0.0) + return 0; + + return (result < 0.0) ? -1 : 1; +} +#endif //0 diff --git a/fs/befs/btree.h b/fs/befs/btree.h new file mode 100644 index 000000000..a253a6276 --- /dev/null +++ b/fs/befs/btree.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * btree.h + * + */ + +int befs_btree_find(struct super_block *sb, const befs_data_stream *ds, + const char *key, befs_off_t *value); + +int befs_btree_read(struct super_block *sb, const befs_data_stream *ds, + loff_t key_no, size_t bufsize, char *keybuf, + size_t *keysize, befs_off_t *value); diff --git a/fs/befs/datastream.c b/fs/befs/datastream.c new file mode 100644 index 000000000..97719a7c7 --- /dev/null +++ b/fs/befs/datastream.c @@ -0,0 +1,525 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/befs/datastream.c + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com> + * + * Based on portions of file.c by Makoto Kato <m_kato@ga2.so-net.ne.jp> + * + * Many thanks to Dominic Giampaolo, author of "Practical File System + * Design with the Be File System", for such a helpful book. + * + */ + +#include <linux/kernel.h> +#include <linux/buffer_head.h> +#include <linux/string.h> + +#include "befs.h" +#include "datastream.h" +#include "io.h" + +const befs_inode_addr BAD_IADDR = { 0, 0, 0 }; + +static int befs_find_brun_direct(struct super_block *sb, + const befs_data_stream *data, + befs_blocknr_t blockno, befs_block_run *run); + +static int befs_find_brun_indirect(struct super_block *sb, + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run); + +static int befs_find_brun_dblindirect(struct super_block *sb, + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run); + +/** + * befs_read_datastream - get buffer_head containing data, starting from pos. + * @sb: Filesystem superblock + * @ds: datastream to find data with + * @pos: start of data + * @off: offset of data in buffer_head->b_data + * + * Returns pointer to buffer_head containing data starting with offset @off, + * if you don't need to know offset just set @off = NULL. + */ +struct buffer_head * +befs_read_datastream(struct super_block *sb, const befs_data_stream *ds, + befs_off_t pos, uint *off) +{ + struct buffer_head *bh; + befs_block_run run; + befs_blocknr_t block; /* block coresponding to pos */ + + befs_debug(sb, "---> %s %llu", __func__, pos); + block = pos >> BEFS_SB(sb)->block_shift; + if (off) + *off = pos - (block << BEFS_SB(sb)->block_shift); + + if (befs_fblock2brun(sb, ds, block, &run) != BEFS_OK) { + befs_error(sb, "BeFS: Error finding disk addr of block %lu", + (unsigned long)block); + befs_debug(sb, "<--- %s ERROR", __func__); + return NULL; + } + bh = befs_bread_iaddr(sb, run); + if (!bh) { + befs_error(sb, "BeFS: Error reading block %lu from datastream", + (unsigned long)block); + return NULL; + } + + befs_debug(sb, "<--- %s read data, starting at %llu", __func__, pos); + + return bh; +} + +/** + * befs_fblock2brun - give back block run for fblock + * @sb: the superblock + * @data: datastream to read from + * @fblock: the blocknumber with the file position to find + * @run: The found run is passed back through this pointer + * + * Takes a file position and gives back a brun who's starting block + * is block number fblock of the file. + * + * Returns BEFS_OK or BEFS_ERR. + * + * Calls specialized functions for each of the three possible + * datastream regions. + */ +int +befs_fblock2brun(struct super_block *sb, const befs_data_stream *data, + befs_blocknr_t fblock, befs_block_run *run) +{ + int err; + befs_off_t pos = fblock << BEFS_SB(sb)->block_shift; + + if (pos < data->max_direct_range) { + err = befs_find_brun_direct(sb, data, fblock, run); + + } else if (pos < data->max_indirect_range) { + err = befs_find_brun_indirect(sb, data, fblock, run); + + } else if (pos < data->max_double_indirect_range) { + err = befs_find_brun_dblindirect(sb, data, fblock, run); + + } else { + befs_error(sb, + "befs_fblock2brun() was asked to find block %lu, " + "which is not mapped by the datastream\n", + (unsigned long)fblock); + err = BEFS_ERR; + } + return err; +} + +/** + * befs_read_lsmylink - read long symlink from datastream. + * @sb: Filesystem superblock + * @ds: Datastream to read from + * @buff: Buffer in which to place long symlink data + * @len: Length of the long symlink in bytes + * + * Returns the number of bytes read + */ +size_t +befs_read_lsymlink(struct super_block *sb, const befs_data_stream *ds, + void *buff, befs_off_t len) +{ + befs_off_t bytes_read = 0; /* bytes readed */ + u16 plen; + struct buffer_head *bh; + + befs_debug(sb, "---> %s length: %llu", __func__, len); + + while (bytes_read < len) { + bh = befs_read_datastream(sb, ds, bytes_read, NULL); + if (!bh) { + befs_error(sb, "BeFS: Error reading datastream block " + "starting from %llu", bytes_read); + befs_debug(sb, "<--- %s ERROR", __func__); + return bytes_read; + + } + plen = ((bytes_read + BEFS_SB(sb)->block_size) < len) ? + BEFS_SB(sb)->block_size : len - bytes_read; + memcpy(buff + bytes_read, bh->b_data, plen); + brelse(bh); + bytes_read += plen; + } + + befs_debug(sb, "<--- %s read %u bytes", __func__, (unsigned int) + bytes_read); + return bytes_read; +} + +/** + * befs_count_blocks - blocks used by a file + * @sb: Filesystem superblock + * @ds: Datastream of the file + * + * Counts the number of fs blocks that the file represented by + * inode occupies on the filesystem, counting both regular file + * data and filesystem metadata (and eventually attribute data + * when we support attributes) +*/ + +befs_blocknr_t +befs_count_blocks(struct super_block *sb, const befs_data_stream *ds) +{ + befs_blocknr_t blocks; + befs_blocknr_t datablocks; /* File data blocks */ + befs_blocknr_t metablocks; /* FS metadata blocks */ + struct befs_sb_info *befs_sb = BEFS_SB(sb); + + befs_debug(sb, "---> %s", __func__); + + datablocks = ds->size >> befs_sb->block_shift; + if (ds->size & (befs_sb->block_size - 1)) + datablocks += 1; + + metablocks = 1; /* Start with 1 block for inode */ + + /* Size of indirect block */ + if (ds->size > ds->max_direct_range) + metablocks += ds->indirect.len; + + /* + * Double indir block, plus all the indirect blocks it maps. + * In the double-indirect range, all block runs of data are + * BEFS_DBLINDIR_BRUN_LEN blocks long. Therefore, we know + * how many data block runs are in the double-indirect region, + * and from that we know how many indirect blocks it takes to + * map them. We assume that the indirect blocks are also + * BEFS_DBLINDIR_BRUN_LEN blocks long. + */ + if (ds->size > ds->max_indirect_range && ds->max_indirect_range != 0) { + uint dbl_bytes; + uint dbl_bruns; + uint indirblocks; + + dbl_bytes = + ds->max_double_indirect_range - ds->max_indirect_range; + dbl_bruns = + dbl_bytes / (befs_sb->block_size * BEFS_DBLINDIR_BRUN_LEN); + indirblocks = dbl_bruns / befs_iaddrs_per_block(sb); + + metablocks += ds->double_indirect.len; + metablocks += indirblocks; + } + + blocks = datablocks + metablocks; + befs_debug(sb, "<--- %s %u blocks", __func__, (unsigned int)blocks); + + return blocks; +} + +/** + * befs_find_brun_direct - find a direct block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the direct region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * Linear search. Checks each element of array[] to see if it + * contains the blockno-th filesystem block. This is necessary + * because the block runs map variable amounts of data. Simply + * keeps a count of the number of blocks searched so far (sum), + * incrementing this by the length of each block run as we come + * across it. Adds sum to *count before returning (this is so + * you can search multiple arrays that are logicaly one array, + * as in the indirect region code). + * + * When/if blockno is found, if blockno is inside of a block + * run as stored on disk, we offset the start and length members + * of the block run, so that blockno is the start and len is + * still valid (the run ends in the same place). + */ +static int +befs_find_brun_direct(struct super_block *sb, const befs_data_stream *data, + befs_blocknr_t blockno, befs_block_run *run) +{ + int i; + const befs_block_run *array = data->direct; + befs_blocknr_t sum; + + befs_debug(sb, "---> %s, find %lu", __func__, (unsigned long)blockno); + + for (i = 0, sum = 0; i < BEFS_NUM_DIRECT_BLOCKS; + sum += array[i].len, i++) { + if (blockno >= sum && blockno < sum + (array[i].len)) { + int offset = blockno - sum; + + run->allocation_group = array[i].allocation_group; + run->start = array[i].start + offset; + run->len = array[i].len - offset; + + befs_debug(sb, "---> %s, " + "found %lu at direct[%d]", __func__, + (unsigned long)blockno, i); + return BEFS_OK; + } + } + + befs_error(sb, "%s failed to find file block %lu", __func__, + (unsigned long)blockno); + befs_debug(sb, "---> %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_find_brun_indirect - find a block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the indirect region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * For each block in the indirect run of the datastream, read + * it in and search through it for search_blk. + * + * XXX: + * Really should check to make sure blockno is inside indirect + * region. + */ +static int +befs_find_brun_indirect(struct super_block *sb, + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run) +{ + int i, j; + befs_blocknr_t sum = 0; + befs_blocknr_t indir_start_blk; + befs_blocknr_t search_blk; + struct buffer_head *indirblock; + befs_disk_block_run *array; + + befs_block_run indirect = data->indirect; + befs_blocknr_t indirblockno = iaddr2blockno(sb, &indirect); + int arraylen = befs_iaddrs_per_block(sb); + + befs_debug(sb, "---> %s, find %lu", __func__, (unsigned long)blockno); + + indir_start_blk = data->max_direct_range >> BEFS_SB(sb)->block_shift; + search_blk = blockno - indir_start_blk; + + /* Examine blocks of the indirect run one at a time */ + for (i = 0; i < indirect.len; i++) { + indirblock = sb_bread(sb, indirblockno + i); + if (indirblock == NULL) { + befs_error(sb, "---> %s failed to read " + "disk block %lu from the indirect brun", + __func__, (unsigned long)indirblockno + i); + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; + } + + array = (befs_disk_block_run *) indirblock->b_data; + + for (j = 0; j < arraylen; ++j) { + int len = fs16_to_cpu(sb, array[j].len); + + if (search_blk >= sum && search_blk < sum + len) { + int offset = search_blk - sum; + run->allocation_group = + fs32_to_cpu(sb, array[j].allocation_group); + run->start = + fs16_to_cpu(sb, array[j].start) + offset; + run->len = + fs16_to_cpu(sb, array[j].len) - offset; + + brelse(indirblock); + befs_debug(sb, + "<--- %s found file block " + "%lu at indirect[%d]", __func__, + (unsigned long)blockno, + j + (i * arraylen)); + return BEFS_OK; + } + sum += len; + } + + brelse(indirblock); + } + + /* Only fallthrough is an error */ + befs_error(sb, "BeFS: %s failed to find " + "file block %lu", __func__, (unsigned long)blockno); + + befs_debug(sb, "<--- %s ERROR", __func__); + return BEFS_ERR; +} + +/** + * befs_find_brun_dblindirect - find a block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the double-indirect region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * The block runs in the double-indirect region are different. + * They are always allocated 4 fs blocks at a time, so each + * block run maps a constant amount of file data. This means + * that we can directly calculate how many block runs into the + * double-indirect region we need to go to get to the one that + * maps a particular filesystem block. + * + * We do this in two stages. First we calculate which of the + * inode addresses in the double-indirect block will point us + * to the indirect block that contains the mapping for the data, + * then we calculate which of the inode addresses in that + * indirect block maps the data block we are after. + * + * Oh, and once we've done that, we actually read in the blocks + * that contain the inode addresses we calculated above. Even + * though the double-indirect run may be several blocks long, + * we can calculate which of those blocks will contain the index + * we are after and only read that one. We then follow it to + * the indirect block and perform a similar process to find + * the actual block run that maps the data block we are interested + * in. + * + * Then we offset the run as in befs_find_brun_array() and we are + * done. + */ +static int +befs_find_brun_dblindirect(struct super_block *sb, + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run) +{ + int dblindir_indx; + int indir_indx; + int offset; + int dbl_which_block; + int which_block; + int dbl_block_indx; + int block_indx; + off_t dblindir_leftover; + befs_blocknr_t blockno_at_run_start; + struct buffer_head *dbl_indir_block; + struct buffer_head *indir_block; + befs_block_run indir_run; + befs_disk_inode_addr *iaddr_array; + + befs_blocknr_t indir_start_blk = + data->max_indirect_range >> BEFS_SB(sb)->block_shift; + + off_t dbl_indir_off = blockno - indir_start_blk; + + /* number of data blocks mapped by each of the iaddrs in + * the indirect block pointed to by the double indirect block + */ + size_t iblklen = BEFS_DBLINDIR_BRUN_LEN; + + /* number of data blocks mapped by each of the iaddrs in + * the double indirect block + */ + size_t diblklen = iblklen * befs_iaddrs_per_block(sb) + * BEFS_DBLINDIR_BRUN_LEN; + + befs_debug(sb, "---> %s find %lu", __func__, (unsigned long)blockno); + + /* First, discover which of the double_indir->indir blocks + * contains pos. Then figure out how much of pos that + * accounted for. Then discover which of the iaddrs in + * the indirect block contains pos. + */ + + dblindir_indx = dbl_indir_off / diblklen; + dblindir_leftover = dbl_indir_off % diblklen; + indir_indx = dblindir_leftover / diblklen; + + /* Read double indirect block */ + dbl_which_block = dblindir_indx / befs_iaddrs_per_block(sb); + if (dbl_which_block > data->double_indirect.len) { + befs_error(sb, "The double-indirect index calculated by " + "%s, %d, is outside the range " + "of the double-indirect block", __func__, + dblindir_indx); + return BEFS_ERR; + } + + dbl_indir_block = + sb_bread(sb, iaddr2blockno(sb, &data->double_indirect) + + dbl_which_block); + if (dbl_indir_block == NULL) { + befs_error(sb, "%s couldn't read the " + "double-indirect block at blockno %lu", __func__, + (unsigned long) + iaddr2blockno(sb, &data->double_indirect) + + dbl_which_block); + return BEFS_ERR; + } + + dbl_block_indx = + dblindir_indx - (dbl_which_block * befs_iaddrs_per_block(sb)); + iaddr_array = (befs_disk_inode_addr *) dbl_indir_block->b_data; + indir_run = fsrun_to_cpu(sb, iaddr_array[dbl_block_indx]); + brelse(dbl_indir_block); + + /* Read indirect block */ + which_block = indir_indx / befs_iaddrs_per_block(sb); + if (which_block > indir_run.len) { + befs_error(sb, "The indirect index calculated by " + "%s, %d, is outside the range " + "of the indirect block", __func__, indir_indx); + return BEFS_ERR; + } + + indir_block = + sb_bread(sb, iaddr2blockno(sb, &indir_run) + which_block); + if (indir_block == NULL) { + befs_error(sb, "%s couldn't read the indirect block " + "at blockno %lu", __func__, (unsigned long) + iaddr2blockno(sb, &indir_run) + which_block); + return BEFS_ERR; + } + + block_indx = indir_indx - (which_block * befs_iaddrs_per_block(sb)); + iaddr_array = (befs_disk_inode_addr *) indir_block->b_data; + *run = fsrun_to_cpu(sb, iaddr_array[block_indx]); + brelse(indir_block); + + blockno_at_run_start = indir_start_blk; + blockno_at_run_start += diblklen * dblindir_indx; + blockno_at_run_start += iblklen * indir_indx; + offset = blockno - blockno_at_run_start; + + run->start += offset; + run->len -= offset; + + befs_debug(sb, "Found file block %lu in double_indirect[%d][%d]," + " double_indirect_leftover = %lu", (unsigned long) + blockno, dblindir_indx, indir_indx, dblindir_leftover); + + return BEFS_OK; +} diff --git a/fs/befs/datastream.h b/fs/befs/datastream.h new file mode 100644 index 000000000..39b1d4766 --- /dev/null +++ b/fs/befs/datastream.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * datastream.h + * + */ + +struct buffer_head *befs_read_datastream(struct super_block *sb, + const befs_data_stream *ds, + befs_off_t pos, uint *off); + +int befs_fblock2brun(struct super_block *sb, const befs_data_stream *data, + befs_blocknr_t fblock, befs_block_run *run); + +size_t befs_read_lsymlink(struct super_block *sb, const befs_data_stream *data, + void *buff, befs_off_t len); + +befs_blocknr_t befs_count_blocks(struct super_block *sb, + const befs_data_stream *ds); + +extern const befs_inode_addr BAD_IADDR; diff --git a/fs/befs/debug.c b/fs/befs/debug.c new file mode 100644 index 000000000..02fa66fb8 --- /dev/null +++ b/fs/befs/debug.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/befs/debug.c + * + * Copyright (C) 2001 Will Dyson (will_dyson at pobox.com) + * + * With help from the ntfs-tng driver by Anton Altparmakov + * + * Copyright (C) 1999 Makoto Kato (m_kato@ga2.so-net.ne.jp) + * + * debug functions + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#ifdef __KERNEL__ + +#include <linux/stdarg.h> +#include <linux/string.h> +#include <linux/spinlock.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/slab.h> + +#endif /* __KERNEL__ */ + +#include "befs.h" + +void +befs_error(const struct super_block *sb, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + pr_err("(%s): %pV\n", sb->s_id, &vaf); + va_end(args); +} + +void +befs_warning(const struct super_block *sb, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + pr_warn("(%s): %pV\n", sb->s_id, &vaf); + va_end(args); +} + +void +befs_debug(const struct super_block *sb, const char *fmt, ...) +{ +#ifdef CONFIG_BEFS_DEBUG + + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + pr_debug("(%s): %pV\n", sb->s_id, &vaf); + va_end(args); + +#endif //CONFIG_BEFS_DEBUG +} + +void +befs_dump_inode(const struct super_block *sb, befs_inode *inode) +{ +#ifdef CONFIG_BEFS_DEBUG + + befs_block_run tmp_run; + + befs_debug(sb, "befs_inode information"); + + befs_debug(sb, " magic1 %08x", fs32_to_cpu(sb, inode->magic1)); + + tmp_run = fsrun_to_cpu(sb, inode->inode_num); + befs_debug(sb, " inode_num %u, %hu, %hu", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + + befs_debug(sb, " uid %u", fs32_to_cpu(sb, inode->uid)); + befs_debug(sb, " gid %u", fs32_to_cpu(sb, inode->gid)); + befs_debug(sb, " mode %08x", fs32_to_cpu(sb, inode->mode)); + befs_debug(sb, " flags %08x", fs32_to_cpu(sb, inode->flags)); + befs_debug(sb, " create_time %llu", + fs64_to_cpu(sb, inode->create_time)); + befs_debug(sb, " last_modified_time %llu", + fs64_to_cpu(sb, inode->last_modified_time)); + + tmp_run = fsrun_to_cpu(sb, inode->parent); + befs_debug(sb, " parent [%u, %hu, %hu]", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + + tmp_run = fsrun_to_cpu(sb, inode->attributes); + befs_debug(sb, " attributes [%u, %hu, %hu]", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + + befs_debug(sb, " type %08x", fs32_to_cpu(sb, inode->type)); + befs_debug(sb, " inode_size %u", fs32_to_cpu(sb, inode->inode_size)); + + if (S_ISLNK(fs32_to_cpu(sb, inode->mode))) { + befs_debug(sb, " Symbolic link [%s]", inode->data.symlink); + } else { + int i; + + for (i = 0; i < BEFS_NUM_DIRECT_BLOCKS; i++) { + tmp_run = + fsrun_to_cpu(sb, inode->data.datastream.direct[i]); + befs_debug(sb, " direct %d [%u, %hu, %hu]", i, + tmp_run.allocation_group, tmp_run.start, + tmp_run.len); + } + befs_debug(sb, " max_direct_range %llu", + fs64_to_cpu(sb, + inode->data.datastream. + max_direct_range)); + + tmp_run = fsrun_to_cpu(sb, inode->data.datastream.indirect); + befs_debug(sb, " indirect [%u, %hu, %hu]", + tmp_run.allocation_group, + tmp_run.start, tmp_run.len); + + befs_debug(sb, " max_indirect_range %llu", + fs64_to_cpu(sb, + inode->data.datastream. + max_indirect_range)); + + tmp_run = + fsrun_to_cpu(sb, inode->data.datastream.double_indirect); + befs_debug(sb, " double indirect [%u, %hu, %hu]", + tmp_run.allocation_group, tmp_run.start, + tmp_run.len); + + befs_debug(sb, " max_double_indirect_range %llu", + fs64_to_cpu(sb, + inode->data.datastream. + max_double_indirect_range)); + + befs_debug(sb, " size %llu", + fs64_to_cpu(sb, inode->data.datastream.size)); + } + +#endif //CONFIG_BEFS_DEBUG +} + +/* + * Display super block structure for debug. + */ + +void +befs_dump_super_block(const struct super_block *sb, befs_super_block *sup) +{ +#ifdef CONFIG_BEFS_DEBUG + + befs_block_run tmp_run; + + befs_debug(sb, "befs_super_block information"); + + befs_debug(sb, " name %s", sup->name); + befs_debug(sb, " magic1 %08x", fs32_to_cpu(sb, sup->magic1)); + befs_debug(sb, " fs_byte_order %08x", + fs32_to_cpu(sb, sup->fs_byte_order)); + + befs_debug(sb, " block_size %u", fs32_to_cpu(sb, sup->block_size)); + befs_debug(sb, " block_shift %u", fs32_to_cpu(sb, sup->block_shift)); + + befs_debug(sb, " num_blocks %llu", fs64_to_cpu(sb, sup->num_blocks)); + befs_debug(sb, " used_blocks %llu", fs64_to_cpu(sb, sup->used_blocks)); + befs_debug(sb, " inode_size %u", fs32_to_cpu(sb, sup->inode_size)); + + befs_debug(sb, " magic2 %08x", fs32_to_cpu(sb, sup->magic2)); + befs_debug(sb, " blocks_per_ag %u", + fs32_to_cpu(sb, sup->blocks_per_ag)); + befs_debug(sb, " ag_shift %u", fs32_to_cpu(sb, sup->ag_shift)); + befs_debug(sb, " num_ags %u", fs32_to_cpu(sb, sup->num_ags)); + + befs_debug(sb, " flags %08x", fs32_to_cpu(sb, sup->flags)); + + tmp_run = fsrun_to_cpu(sb, sup->log_blocks); + befs_debug(sb, " log_blocks %u, %hu, %hu", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + + befs_debug(sb, " log_start %lld", fs64_to_cpu(sb, sup->log_start)); + befs_debug(sb, " log_end %lld", fs64_to_cpu(sb, sup->log_end)); + + befs_debug(sb, " magic3 %08x", fs32_to_cpu(sb, sup->magic3)); + + tmp_run = fsrun_to_cpu(sb, sup->root_dir); + befs_debug(sb, " root_dir %u, %hu, %hu", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + + tmp_run = fsrun_to_cpu(sb, sup->indices); + befs_debug(sb, " indices %u, %hu, %hu", + tmp_run.allocation_group, tmp_run.start, tmp_run.len); + +#endif //CONFIG_BEFS_DEBUG +} + +#if 0 +/* unused */ +void +befs_dump_small_data(const struct super_block *sb, befs_small_data *sd) +{ +} + +/* unused */ +void +befs_dump_run(const struct super_block *sb, befs_disk_block_run run) +{ +#ifdef CONFIG_BEFS_DEBUG + + befs_block_run n = fsrun_to_cpu(sb, run); + + befs_debug(sb, "[%u, %hu, %hu]", n.allocation_group, n.start, n.len); + +#endif //CONFIG_BEFS_DEBUG +} +#endif /* 0 */ + +void +befs_dump_index_entry(const struct super_block *sb, + befs_disk_btree_super *super) +{ +#ifdef CONFIG_BEFS_DEBUG + + befs_debug(sb, "Btree super structure"); + befs_debug(sb, " magic %08x", fs32_to_cpu(sb, super->magic)); + befs_debug(sb, " node_size %u", fs32_to_cpu(sb, super->node_size)); + befs_debug(sb, " max_depth %08x", fs32_to_cpu(sb, super->max_depth)); + + befs_debug(sb, " data_type %08x", fs32_to_cpu(sb, super->data_type)); + befs_debug(sb, " root_node_pointer %016LX", + fs64_to_cpu(sb, super->root_node_ptr)); + befs_debug(sb, " free_node_pointer %016LX", + fs64_to_cpu(sb, super->free_node_ptr)); + befs_debug(sb, " maximum size %016LX", + fs64_to_cpu(sb, super->max_size)); + +#endif //CONFIG_BEFS_DEBUG +} + +void +befs_dump_index_node(const struct super_block *sb, befs_btree_nodehead *node) +{ +#ifdef CONFIG_BEFS_DEBUG + + befs_debug(sb, "Btree node structure"); + befs_debug(sb, " left %016LX", fs64_to_cpu(sb, node->left)); + befs_debug(sb, " right %016LX", fs64_to_cpu(sb, node->right)); + befs_debug(sb, " overflow %016LX", fs64_to_cpu(sb, node->overflow)); + befs_debug(sb, " all_key_count %hu", + fs16_to_cpu(sb, node->all_key_count)); + befs_debug(sb, " all_key_length %hu", + fs16_to_cpu(sb, node->all_key_length)); + +#endif //CONFIG_BEFS_DEBUG +} diff --git a/fs/befs/endian.h b/fs/befs/endian.h new file mode 100644 index 000000000..bb55a54c2 --- /dev/null +++ b/fs/befs/endian.h @@ -0,0 +1,126 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * linux/fs/befs/endian.h + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com> + * + * Partially based on similar funtions in the sysv driver. + */ + +#ifndef LINUX_BEFS_ENDIAN +#define LINUX_BEFS_ENDIAN + +#include <asm/byteorder.h> + +static inline u64 +fs64_to_cpu(const struct super_block *sb, fs64 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return le64_to_cpu((__force __le64)n); + else + return be64_to_cpu((__force __be64)n); +} + +static inline fs64 +cpu_to_fs64(const struct super_block *sb, u64 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return (__force fs64)cpu_to_le64(n); + else + return (__force fs64)cpu_to_be64(n); +} + +static inline u32 +fs32_to_cpu(const struct super_block *sb, fs32 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return le32_to_cpu((__force __le32)n); + else + return be32_to_cpu((__force __be32)n); +} + +static inline fs32 +cpu_to_fs32(const struct super_block *sb, u32 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return (__force fs32)cpu_to_le32(n); + else + return (__force fs32)cpu_to_be32(n); +} + +static inline u16 +fs16_to_cpu(const struct super_block *sb, fs16 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return le16_to_cpu((__force __le16)n); + else + return be16_to_cpu((__force __be16)n); +} + +static inline fs16 +cpu_to_fs16(const struct super_block *sb, u16 n) +{ + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) + return (__force fs16)cpu_to_le16(n); + else + return (__force fs16)cpu_to_be16(n); +} + +/* Composite types below here */ + +static inline befs_block_run +fsrun_to_cpu(const struct super_block *sb, befs_disk_block_run n) +{ + befs_block_run run; + + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) { + run.allocation_group = le32_to_cpu((__force __le32)n.allocation_group); + run.start = le16_to_cpu((__force __le16)n.start); + run.len = le16_to_cpu((__force __le16)n.len); + } else { + run.allocation_group = be32_to_cpu((__force __be32)n.allocation_group); + run.start = be16_to_cpu((__force __be16)n.start); + run.len = be16_to_cpu((__force __be16)n.len); + } + return run; +} + +static inline befs_disk_block_run +cpu_to_fsrun(const struct super_block *sb, befs_block_run n) +{ + befs_disk_block_run run; + + if (BEFS_SB(sb)->byte_order == BEFS_BYTESEX_LE) { + run.allocation_group = cpu_to_le32(n.allocation_group); + run.start = cpu_to_le16(n.start); + run.len = cpu_to_le16(n.len); + } else { + run.allocation_group = cpu_to_be32(n.allocation_group); + run.start = cpu_to_be16(n.start); + run.len = cpu_to_be16(n.len); + } + return run; +} + +static inline befs_data_stream +fsds_to_cpu(const struct super_block *sb, const befs_disk_data_stream *n) +{ + befs_data_stream data; + int i; + + for (i = 0; i < BEFS_NUM_DIRECT_BLOCKS; ++i) + data.direct[i] = fsrun_to_cpu(sb, n->direct[i]); + + data.max_direct_range = fs64_to_cpu(sb, n->max_direct_range); + data.indirect = fsrun_to_cpu(sb, n->indirect); + data.max_indirect_range = fs64_to_cpu(sb, n->max_indirect_range); + data.double_indirect = fsrun_to_cpu(sb, n->double_indirect); + data.max_double_indirect_range = fs64_to_cpu(sb, + n-> + max_double_indirect_range); + data.size = fs64_to_cpu(sb, n->size); + + return data; +} + +#endif //LINUX_BEFS_ENDIAN diff --git a/fs/befs/inode.c b/fs/befs/inode.c new file mode 100644 index 000000000..791b46a6f --- /dev/null +++ b/fs/befs/inode.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * inode.c + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com> + */ + +#include <linux/fs.h> + +#include "befs.h" +#include "inode.h" + +/* + * Validates the correctness of the befs inode + * Returns BEFS_OK if the inode should be used, otherwise + * returns BEFS_BAD_INODE + */ +int +befs_check_inode(struct super_block *sb, befs_inode *raw_inode, + befs_blocknr_t inode) +{ + u32 magic1 = fs32_to_cpu(sb, raw_inode->magic1); + befs_inode_addr ino_num = fsrun_to_cpu(sb, raw_inode->inode_num); + u32 flags = fs32_to_cpu(sb, raw_inode->flags); + + /* check magic header. */ + if (magic1 != BEFS_INODE_MAGIC1) { + befs_error(sb, + "Inode has a bad magic header - inode = %lu", + (unsigned long)inode); + return BEFS_BAD_INODE; + } + + /* + * Sanity check2: inodes store their own block address. Check it. + */ + if (inode != iaddr2blockno(sb, &ino_num)) { + befs_error(sb, "inode blocknr field disagrees with vfs " + "VFS: %lu, Inode %lu", (unsigned long) + inode, (unsigned long)iaddr2blockno(sb, &ino_num)); + return BEFS_BAD_INODE; + } + + /* + * check flag + */ + + if (!(flags & BEFS_INODE_IN_USE)) { + befs_error(sb, "inode is not used - inode = %lu", + (unsigned long)inode); + return BEFS_BAD_INODE; + } + + return BEFS_OK; +} diff --git a/fs/befs/inode.h b/fs/befs/inode.h new file mode 100644 index 000000000..2219e412f --- /dev/null +++ b/fs/befs/inode.h @@ -0,0 +1,7 @@ +/* + * inode.h + * + */ + +int befs_check_inode(struct super_block *sb, befs_inode *raw_inode, + befs_blocknr_t inode); diff --git a/fs/befs/io.c b/fs/befs/io.c new file mode 100644 index 000000000..2caf50a4a --- /dev/null +++ b/fs/befs/io.c @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/befs/io.c + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com + * + * Based on portions of file.c and inode.c + * by Makoto Kato (m_kato@ga2.so-net.ne.jp) + * + * Many thanks to Dominic Giampaolo, author of Practical File System + * Design with the Be File System, for such a helpful book. + * + */ + +#include <linux/buffer_head.h> + +#include "befs.h" +#include "io.h" + +/* + * Converts befs notion of disk addr to a disk offset and uses + * linux kernel function sb_bread() to get the buffer containing + * the offset. + */ + +struct buffer_head * +befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr) +{ + struct buffer_head *bh; + befs_blocknr_t block; + struct befs_sb_info *befs_sb = BEFS_SB(sb); + + befs_debug(sb, "---> Enter %s " + "[%u, %hu, %hu]", __func__, iaddr.allocation_group, + iaddr.start, iaddr.len); + + if (iaddr.allocation_group > befs_sb->num_ags) { + befs_error(sb, "BEFS: Invalid allocation group %u, max is %u", + iaddr.allocation_group, befs_sb->num_ags); + goto error; + } + + block = iaddr2blockno(sb, &iaddr); + + befs_debug(sb, "%s: offset = %lu", __func__, (unsigned long)block); + + bh = sb_bread(sb, block); + + if (bh == NULL) { + befs_error(sb, "Failed to read block %lu", + (unsigned long)block); + goto error; + } + + befs_debug(sb, "<--- %s", __func__); + return bh; + +error: + befs_debug(sb, "<--- %s ERROR", __func__); + return NULL; +} diff --git a/fs/befs/io.h b/fs/befs/io.h new file mode 100644 index 000000000..9b3e1967c --- /dev/null +++ b/fs/befs/io.h @@ -0,0 +1,6 @@ +/* + * io.h + */ + +struct buffer_head *befs_bread_iaddr(struct super_block *sb, + befs_inode_addr iaddr); diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c new file mode 100644 index 000000000..32749fcee --- /dev/null +++ b/fs/befs/linuxvfs.c @@ -0,0 +1,1027 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/befs/linuxvfs.c + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/errno.h> +#include <linux/stat.h> +#include <linux/nls.h> +#include <linux/buffer_head.h> +#include <linux/vfs.h> +#include <linux/parser.h> +#include <linux/namei.h> +#include <linux/sched.h> +#include <linux/cred.h> +#include <linux/exportfs.h> +#include <linux/seq_file.h> +#include <linux/blkdev.h> + +#include "befs.h" +#include "btree.h" +#include "inode.h" +#include "datastream.h" +#include "super.h" +#include "io.h" + +MODULE_DESCRIPTION("BeOS File System (BeFS) driver"); +MODULE_AUTHOR("Will Dyson"); +MODULE_LICENSE("GPL"); + +/* The units the vfs expects inode->i_blocks to be in */ +#define VFS_BLOCK_SIZE 512 + +static int befs_readdir(struct file *, struct dir_context *); +static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int); +static int befs_read_folio(struct file *file, struct folio *folio); +static sector_t befs_bmap(struct address_space *mapping, sector_t block); +static struct dentry *befs_lookup(struct inode *, struct dentry *, + unsigned int); +static struct inode *befs_iget(struct super_block *, unsigned long); +static struct inode *befs_alloc_inode(struct super_block *sb); +static void befs_free_inode(struct inode *inode); +static void befs_destroy_inodecache(void); +static int befs_symlink_read_folio(struct file *, struct folio *); +static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, + char **out, int *out_len); +static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, + char **out, int *out_len); +static void befs_put_super(struct super_block *); +static int befs_remount(struct super_block *, int *, char *); +static int befs_statfs(struct dentry *, struct kstatfs *); +static int befs_show_options(struct seq_file *, struct dentry *); +static int parse_options(char *, struct befs_mount_options *); +static struct dentry *befs_fh_to_dentry(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type); +static struct dentry *befs_fh_to_parent(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type); +static struct dentry *befs_get_parent(struct dentry *child); + +static const struct super_operations befs_sops = { + .alloc_inode = befs_alloc_inode, /* allocate a new inode */ + .free_inode = befs_free_inode, /* deallocate an inode */ + .put_super = befs_put_super, /* uninit super */ + .statfs = befs_statfs, /* statfs */ + .remount_fs = befs_remount, + .show_options = befs_show_options, +}; + +/* slab cache for befs_inode_info objects */ +static struct kmem_cache *befs_inode_cachep; + +static const struct file_operations befs_dir_operations = { + .read = generic_read_dir, + .iterate_shared = befs_readdir, + .llseek = generic_file_llseek, +}; + +static const struct inode_operations befs_dir_inode_operations = { + .lookup = befs_lookup, +}; + +static const struct address_space_operations befs_aops = { + .read_folio = befs_read_folio, + .bmap = befs_bmap, +}; + +static const struct address_space_operations befs_symlink_aops = { + .read_folio = befs_symlink_read_folio, +}; + +static const struct export_operations befs_export_operations = { + .fh_to_dentry = befs_fh_to_dentry, + .fh_to_parent = befs_fh_to_parent, + .get_parent = befs_get_parent, +}; + +/* + * Called by generic_file_read() to read a folio of data + * + * In turn, simply calls a generic block read function and + * passes it the address of befs_get_block, for mapping file + * positions to disk blocks. + */ +static int befs_read_folio(struct file *file, struct folio *folio) +{ + return block_read_full_folio(folio, befs_get_block); +} + +static sector_t +befs_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping, block, befs_get_block); +} + +/* + * Generic function to map a file position (block) to a + * disk offset (passed back in bh_result). + * + * Used by many higher level functions. + * + * Calls befs_fblock2brun() in datastream.c to do the real work. + */ + +static int +befs_get_block(struct inode *inode, sector_t block, + struct buffer_head *bh_result, int create) +{ + struct super_block *sb = inode->i_sb; + befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; + befs_block_run run = BAD_IADDR; + int res; + ulong disk_off; + + befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", + (unsigned long)inode->i_ino, (long)block); + if (create) { + befs_error(sb, "befs_get_block() was asked to write to " + "block %ld in inode %lu", (long)block, + (unsigned long)inode->i_ino); + return -EPERM; + } + + res = befs_fblock2brun(sb, ds, block, &run); + if (res != BEFS_OK) { + befs_error(sb, + "<--- %s for inode %lu, block %ld ERROR", + __func__, (unsigned long)inode->i_ino, + (long)block); + return -EFBIG; + } + + disk_off = (ulong) iaddr2blockno(sb, &run); + + map_bh(bh_result, inode->i_sb, disk_off); + + befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", + __func__, (unsigned long)inode->i_ino, (long)block, + (unsigned long)disk_off); + + return 0; +} + +static struct dentry * +befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) +{ + struct inode *inode; + struct super_block *sb = dir->i_sb; + const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; + befs_off_t offset; + int ret; + int utfnamelen; + char *utfname; + const char *name = dentry->d_name.name; + + befs_debug(sb, "---> %s name %pd inode %ld", __func__, + dentry, dir->i_ino); + + /* Convert to UTF-8 */ + if (BEFS_SB(sb)->nls) { + ret = + befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); + if (ret < 0) { + befs_debug(sb, "<--- %s ERROR", __func__); + return ERR_PTR(ret); + } + ret = befs_btree_find(sb, ds, utfname, &offset); + kfree(utfname); + + } else { + ret = befs_btree_find(sb, ds, name, &offset); + } + + if (ret == BEFS_BT_NOT_FOUND) { + befs_debug(sb, "<--- %s %pd not found", __func__, dentry); + inode = NULL; + } else if (ret != BEFS_OK || offset == 0) { + befs_error(sb, "<--- %s Error", __func__); + inode = ERR_PTR(-ENODATA); + } else { + inode = befs_iget(dir->i_sb, (ino_t) offset); + } + befs_debug(sb, "<--- %s", __func__); + + return d_splice_alias(inode, dentry); +} + +static int +befs_readdir(struct file *file, struct dir_context *ctx) +{ + struct inode *inode = file_inode(file); + struct super_block *sb = inode->i_sb; + const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; + befs_off_t value; + int result; + size_t keysize; + char keybuf[BEFS_NAME_LEN + 1]; + + befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", + __func__, file, inode->i_ino, ctx->pos); + + while (1) { + result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, + keybuf, &keysize, &value); + + if (result == BEFS_ERR) { + befs_debug(sb, "<--- %s ERROR", __func__); + befs_error(sb, "IO error reading %pD (inode %lu)", + file, inode->i_ino); + return -EIO; + + } else if (result == BEFS_BT_END) { + befs_debug(sb, "<--- %s END", __func__); + return 0; + + } else if (result == BEFS_BT_EMPTY) { + befs_debug(sb, "<--- %s Empty directory", __func__); + return 0; + } + + /* Convert to NLS */ + if (BEFS_SB(sb)->nls) { + char *nlsname; + int nlsnamelen; + + result = + befs_utf2nls(sb, keybuf, keysize, &nlsname, + &nlsnamelen); + if (result < 0) { + befs_debug(sb, "<--- %s ERROR", __func__); + return result; + } + if (!dir_emit(ctx, nlsname, nlsnamelen, + (ino_t) value, DT_UNKNOWN)) { + kfree(nlsname); + return 0; + } + kfree(nlsname); + } else { + if (!dir_emit(ctx, keybuf, keysize, + (ino_t) value, DT_UNKNOWN)) + return 0; + } + ctx->pos++; + } +} + +static struct inode * +befs_alloc_inode(struct super_block *sb) +{ + struct befs_inode_info *bi; + + bi = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL); + if (!bi) + return NULL; + return &bi->vfs_inode; +} + +static void befs_free_inode(struct inode *inode) +{ + kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); +} + +static void init_once(void *foo) +{ + struct befs_inode_info *bi = (struct befs_inode_info *) foo; + + inode_init_once(&bi->vfs_inode); +} + +static struct inode *befs_iget(struct super_block *sb, unsigned long ino) +{ + struct buffer_head *bh; + befs_inode *raw_inode; + struct befs_sb_info *befs_sb = BEFS_SB(sb); + struct befs_inode_info *befs_ino; + struct inode *inode; + + befs_debug(sb, "---> %s inode = %lu", __func__, ino); + + inode = iget_locked(sb, ino); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + befs_ino = BEFS_I(inode); + + /* convert from vfs's inode number to befs's inode number */ + befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); + + befs_debug(sb, " real inode number [%u, %hu, %hu]", + befs_ino->i_inode_num.allocation_group, + befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); + + bh = sb_bread(sb, inode->i_ino); + if (!bh) { + befs_error(sb, "unable to read inode block - " + "inode = %lu", inode->i_ino); + goto unacquire_none; + } + + raw_inode = (befs_inode *) bh->b_data; + + befs_dump_inode(sb, raw_inode); + + if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { + befs_error(sb, "Bad inode: %lu", inode->i_ino); + goto unacquire_bh; + } + + inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); + + /* + * set uid and gid. But since current BeOS is single user OS, so + * you can change by "uid" or "gid" options. + */ + + inode->i_uid = befs_sb->mount_opts.use_uid ? + befs_sb->mount_opts.uid : + make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); + inode->i_gid = befs_sb->mount_opts.use_gid ? + befs_sb->mount_opts.gid : + make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); + + set_nlink(inode, 1); + + /* + * BEFS's time is 64 bits, but current VFS is 32 bits... + * BEFS don't have access time. Nor inode change time. VFS + * doesn't have creation time. + * Also, the lower 16 bits of the last_modified_time and + * create_time are just a counter to help ensure uniqueness + * for indexing purposes. (PFD, page 54) + */ + + inode->i_mtime.tv_sec = + fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16; + inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */ + inode->i_ctime = inode->i_mtime; + inode->i_atime = inode->i_mtime; + + befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); + befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); + befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); + befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); + + if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ + inode->i_size = 0; + inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; + strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink, + BEFS_SYMLINK_LEN); + } else { + int num_blks; + + befs_ino->i_data.ds = + fsds_to_cpu(sb, &raw_inode->data.datastream); + + num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); + inode->i_blocks = + num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); + inode->i_size = befs_ino->i_data.ds.size; + } + + inode->i_mapping->a_ops = &befs_aops; + + if (S_ISREG(inode->i_mode)) { + inode->i_fop = &generic_ro_fops; + } else if (S_ISDIR(inode->i_mode)) { + inode->i_op = &befs_dir_inode_operations; + inode->i_fop = &befs_dir_operations; + } else if (S_ISLNK(inode->i_mode)) { + if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { + inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); + inode->i_mapping->a_ops = &befs_symlink_aops; + } else { + inode->i_link = befs_ino->i_data.symlink; + inode->i_op = &simple_symlink_inode_operations; + } + } else { + befs_error(sb, "Inode %lu is not a regular file, " + "directory or symlink. THAT IS WRONG! BeFS has no " + "on disk special files", inode->i_ino); + goto unacquire_bh; + } + + brelse(bh); + befs_debug(sb, "<--- %s", __func__); + unlock_new_inode(inode); + return inode; + +unacquire_bh: + brelse(bh); + +unacquire_none: + iget_failed(inode); + befs_debug(sb, "<--- %s - Bad inode", __func__); + return ERR_PTR(-EIO); +} + +/* Initialize the inode cache. Called at fs setup. + * + * Taken from NFS implementation by Al Viro. + */ +static int __init +befs_init_inodecache(void) +{ + befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache", + sizeof(struct befs_inode_info), 0, + (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| + SLAB_ACCOUNT), + offsetof(struct befs_inode_info, + i_data.symlink), + sizeof_field(struct befs_inode_info, + i_data.symlink), + init_once); + if (befs_inode_cachep == NULL) + return -ENOMEM; + + return 0; +} + +/* Called at fs teardown. + * + * Taken from NFS implementation by Al Viro. + */ +static void +befs_destroy_inodecache(void) +{ + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(befs_inode_cachep); +} + +/* + * The inode of symbolic link is different to data stream. + * The data stream become link name. Unless the LONG_SYMLINK + * flag is set. + */ +static int befs_symlink_read_folio(struct file *unused, struct folio *folio) +{ + struct inode *inode = folio->mapping->host; + struct super_block *sb = inode->i_sb; + struct befs_inode_info *befs_ino = BEFS_I(inode); + befs_data_stream *data = &befs_ino->i_data.ds; + befs_off_t len = data->size; + char *link = folio_address(folio); + + if (len == 0 || len > PAGE_SIZE) { + befs_error(sb, "Long symlink with illegal length"); + goto fail; + } + befs_debug(sb, "Follow long symlink"); + + if (befs_read_lsymlink(sb, data, link, len) != len) { + befs_error(sb, "Failed to read entire long symlink"); + goto fail; + } + link[len - 1] = '\0'; + folio_mark_uptodate(folio); + folio_unlock(folio); + return 0; +fail: + folio_set_error(folio); + folio_unlock(folio); + return -EIO; +} + +/* + * UTF-8 to NLS charset convert routine + * + * Uses uni2char() / char2uni() rather than the nls tables directly + */ +static int +befs_utf2nls(struct super_block *sb, const char *in, + int in_len, char **out, int *out_len) +{ + struct nls_table *nls = BEFS_SB(sb)->nls; + int i, o; + unicode_t uni; + int unilen, utflen; + char *result; + /* The utf8->nls conversion won't make the final nls string bigger + * than the utf one, but if the string is pure ascii they'll have the + * same width and an extra char is needed to save the additional \0 + */ + int maxlen = in_len + 1; + + befs_debug(sb, "---> %s", __func__); + + if (!nls) { + befs_error(sb, "%s called with no NLS table loaded", __func__); + return -EINVAL; + } + + *out = result = kmalloc(maxlen, GFP_NOFS); + if (!*out) + return -ENOMEM; + + for (i = o = 0; i < in_len; i += utflen, o += unilen) { + + /* convert from UTF-8 to Unicode */ + utflen = utf8_to_utf32(&in[i], in_len - i, &uni); + if (utflen < 0) + goto conv_err; + + /* convert from Unicode to nls */ + if (uni > MAX_WCHAR_T) + goto conv_err; + unilen = nls->uni2char(uni, &result[o], in_len - o); + if (unilen < 0) + goto conv_err; + } + result[o] = '\0'; + *out_len = o; + + befs_debug(sb, "<--- %s", __func__); + + return o; + +conv_err: + befs_error(sb, "Name using character set %s contains a character that " + "cannot be converted to unicode.", nls->charset); + befs_debug(sb, "<--- %s", __func__); + kfree(result); + return -EILSEQ; +} + +/** + * befs_nls2utf - Convert NLS string to utf8 encodeing + * @sb: Superblock + * @in: Input string buffer in NLS format + * @in_len: Length of input string in bytes + * @out: The output string in UTF-8 format + * @out_len: Length of the output buffer + * + * Converts input string @in, which is in the format of the loaded NLS map, + * into a utf8 string. + * + * The destination string @out is allocated by this function and the caller is + * responsible for freeing it with kfree() + * + * On return, *@out_len is the length of @out in bytes. + * + * On success, the return value is the number of utf8 characters written to + * the output buffer @out. + * + * On Failure, a negative number coresponding to the error code is returned. + */ + +static int +befs_nls2utf(struct super_block *sb, const char *in, + int in_len, char **out, int *out_len) +{ + struct nls_table *nls = BEFS_SB(sb)->nls; + int i, o; + wchar_t uni; + int unilen, utflen; + char *result; + /* + * There are nls characters that will translate to 3-chars-wide UTF-8 + * characters, an additional byte is needed to save the final \0 + * in special cases + */ + int maxlen = (3 * in_len) + 1; + + befs_debug(sb, "---> %s\n", __func__); + + if (!nls) { + befs_error(sb, "%s called with no NLS table loaded.", + __func__); + return -EINVAL; + } + + *out = result = kmalloc(maxlen, GFP_NOFS); + if (!*out) { + *out_len = 0; + return -ENOMEM; + } + + for (i = o = 0; i < in_len; i += unilen, o += utflen) { + + /* convert from nls to unicode */ + unilen = nls->char2uni(&in[i], in_len - i, &uni); + if (unilen < 0) + goto conv_err; + + /* convert from unicode to UTF-8 */ + utflen = utf32_to_utf8(uni, &result[o], 3); + if (utflen <= 0) + goto conv_err; + } + + result[o] = '\0'; + *out_len = o; + + befs_debug(sb, "<--- %s", __func__); + + return i; + +conv_err: + befs_error(sb, "Name using character set %s contains a character that " + "cannot be converted to unicode.", nls->charset); + befs_debug(sb, "<--- %s", __func__); + kfree(result); + return -EILSEQ; +} + +static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino, + uint32_t generation) +{ + /* No need to handle i_generation */ + return befs_iget(sb, ino); +} + +/* + * Map a NFS file handle to a corresponding dentry + */ +static struct dentry *befs_fh_to_dentry(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type) +{ + return generic_fh_to_dentry(sb, fid, fh_len, fh_type, + befs_nfs_get_inode); +} + +/* + * Find the parent for a file specified by NFS handle + */ +static struct dentry *befs_fh_to_parent(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type) +{ + return generic_fh_to_parent(sb, fid, fh_len, fh_type, + befs_nfs_get_inode); +} + +static struct dentry *befs_get_parent(struct dentry *child) +{ + struct inode *parent; + struct befs_inode_info *befs_ino = BEFS_I(d_inode(child)); + + parent = befs_iget(child->d_sb, + (unsigned long)befs_ino->i_parent.start); + if (IS_ERR(parent)) + return ERR_CAST(parent); + + return d_obtain_alias(parent); +} + +enum { + Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, +}; + +static const match_table_t befs_tokens = { + {Opt_uid, "uid=%d"}, + {Opt_gid, "gid=%d"}, + {Opt_charset, "iocharset=%s"}, + {Opt_debug, "debug"}, + {Opt_err, NULL} +}; + +static int +parse_options(char *options, struct befs_mount_options *opts) +{ + char *p; + substring_t args[MAX_OPT_ARGS]; + int option; + kuid_t uid; + kgid_t gid; + + /* Initialize options */ + opts->uid = GLOBAL_ROOT_UID; + opts->gid = GLOBAL_ROOT_GID; + opts->use_uid = 0; + opts->use_gid = 0; + opts->iocharset = NULL; + opts->debug = 0; + + if (!options) + return 1; + + while ((p = strsep(&options, ",")) != NULL) { + int token; + + if (!*p) + continue; + + token = match_token(p, befs_tokens, args); + switch (token) { + case Opt_uid: + if (match_int(&args[0], &option)) + return 0; + uid = INVALID_UID; + if (option >= 0) + uid = make_kuid(current_user_ns(), option); + if (!uid_valid(uid)) { + pr_err("Invalid uid %d, " + "using default\n", option); + break; + } + opts->uid = uid; + opts->use_uid = 1; + break; + case Opt_gid: + if (match_int(&args[0], &option)) + return 0; + gid = INVALID_GID; + if (option >= 0) + gid = make_kgid(current_user_ns(), option); + if (!gid_valid(gid)) { + pr_err("Invalid gid %d, " + "using default\n", option); + break; + } + opts->gid = gid; + opts->use_gid = 1; + break; + case Opt_charset: + kfree(opts->iocharset); + opts->iocharset = match_strdup(&args[0]); + if (!opts->iocharset) { + pr_err("allocation failure for " + "iocharset string\n"); + return 0; + } + break; + case Opt_debug: + opts->debug = 1; + break; + default: + pr_err("Unrecognized mount option \"%s\" " + "or missing value\n", p); + return 0; + } + } + return 1; +} + +static int befs_show_options(struct seq_file *m, struct dentry *root) +{ + struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb); + struct befs_mount_options *opts = &befs_sb->mount_opts; + + if (!uid_eq(opts->uid, GLOBAL_ROOT_UID)) + seq_printf(m, ",uid=%u", + from_kuid_munged(&init_user_ns, opts->uid)); + if (!gid_eq(opts->gid, GLOBAL_ROOT_GID)) + seq_printf(m, ",gid=%u", + from_kgid_munged(&init_user_ns, opts->gid)); + if (opts->iocharset) + seq_printf(m, ",charset=%s", opts->iocharset); + if (opts->debug) + seq_puts(m, ",debug"); + return 0; +} + +/* This function has the responsibiltiy of getting the + * filesystem ready for unmounting. + * Basically, we free everything that we allocated in + * befs_read_inode + */ +static void +befs_put_super(struct super_block *sb) +{ + kfree(BEFS_SB(sb)->mount_opts.iocharset); + BEFS_SB(sb)->mount_opts.iocharset = NULL; + unload_nls(BEFS_SB(sb)->nls); + kfree(sb->s_fs_info); + sb->s_fs_info = NULL; +} + +/* Allocate private field of the superblock, fill it. + * + * Finish filling the public superblock fields + * Make the root directory + * Load a set of NLS translations if needed. + */ +static int +befs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct buffer_head *bh; + struct befs_sb_info *befs_sb; + befs_super_block *disk_sb; + struct inode *root; + long ret = -EINVAL; + const unsigned long sb_block = 0; + const off_t x86_sb_off = 512; + int blocksize; + + sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); + if (sb->s_fs_info == NULL) + goto unacquire_none; + + befs_sb = BEFS_SB(sb); + + if (!parse_options((char *) data, &befs_sb->mount_opts)) { + if (!silent) + befs_error(sb, "cannot parse mount options"); + goto unacquire_priv_sbp; + } + + befs_debug(sb, "---> %s", __func__); + + if (!sb_rdonly(sb)) { + befs_warning(sb, + "No write support. Marking filesystem read-only"); + sb->s_flags |= SB_RDONLY; + } + + /* + * Set dummy blocksize to read super block. + * Will be set to real fs blocksize later. + * + * Linux 2.4.10 and later refuse to read blocks smaller than + * the logical block size for the device. But we also need to read at + * least 1k to get the second 512 bytes of the volume. + */ + blocksize = sb_min_blocksize(sb, 1024); + if (!blocksize) { + if (!silent) + befs_error(sb, "unable to set blocksize"); + goto unacquire_priv_sbp; + } + + bh = sb_bread(sb, sb_block); + if (!bh) { + if (!silent) + befs_error(sb, "unable to read superblock"); + goto unacquire_priv_sbp; + } + + /* account for offset of super block on x86 */ + disk_sb = (befs_super_block *) bh->b_data; + if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) || + (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) { + befs_debug(sb, "Using PPC superblock location"); + } else { + befs_debug(sb, "Using x86 superblock location"); + disk_sb = + (befs_super_block *) ((void *) bh->b_data + x86_sb_off); + } + + if ((befs_load_sb(sb, disk_sb) != BEFS_OK) || + (befs_check_sb(sb) != BEFS_OK)) + goto unacquire_bh; + + befs_dump_super_block(sb, disk_sb); + + brelse(bh); + + if (befs_sb->num_blocks > ~((sector_t)0)) { + if (!silent) + befs_error(sb, "blocks count: %llu is larger than the host can use", + befs_sb->num_blocks); + goto unacquire_priv_sbp; + } + + /* + * set up enough so that it can read an inode + * Fill in kernel superblock fields from private sb + */ + sb->s_magic = BEFS_SUPER_MAGIC; + /* Set real blocksize of fs */ + sb_set_blocksize(sb, (ulong) befs_sb->block_size); + sb->s_op = &befs_sops; + sb->s_export_op = &befs_export_operations; + sb->s_time_min = 0; + sb->s_time_max = 0xffffffffffffll; + root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto unacquire_priv_sbp; + } + sb->s_root = d_make_root(root); + if (!sb->s_root) { + if (!silent) + befs_error(sb, "get root inode failed"); + goto unacquire_priv_sbp; + } + + /* load nls library */ + if (befs_sb->mount_opts.iocharset) { + befs_debug(sb, "Loading nls: %s", + befs_sb->mount_opts.iocharset); + befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset); + if (!befs_sb->nls) { + befs_warning(sb, "Cannot load nls %s" + " loading default nls", + befs_sb->mount_opts.iocharset); + befs_sb->nls = load_nls_default(); + } + /* load default nls if none is specified in mount options */ + } else { + befs_debug(sb, "Loading default nls"); + befs_sb->nls = load_nls_default(); + } + + return 0; + +unacquire_bh: + brelse(bh); + +unacquire_priv_sbp: + kfree(befs_sb->mount_opts.iocharset); + kfree(sb->s_fs_info); + sb->s_fs_info = NULL; + +unacquire_none: + return ret; +} + +static int +befs_remount(struct super_block *sb, int *flags, char *data) +{ + sync_filesystem(sb); + if (!(*flags & SB_RDONLY)) + return -EINVAL; + return 0; +} + +static int +befs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + + befs_debug(sb, "---> %s", __func__); + + buf->f_type = BEFS_SUPER_MAGIC; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = BEFS_SB(sb)->num_blocks; + buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks; + buf->f_bavail = buf->f_bfree; + buf->f_files = 0; /* UNKNOWN */ + buf->f_ffree = 0; /* UNKNOWN */ + buf->f_fsid = u64_to_fsid(id); + buf->f_namelen = BEFS_NAME_LEN; + + befs_debug(sb, "<--- %s", __func__); + + return 0; +} + +static struct dentry * +befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, + void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); +} + +static struct file_system_type befs_fs_type = { + .owner = THIS_MODULE, + .name = "befs", + .mount = befs_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("befs"); + +static int __init +init_befs_fs(void) +{ + int err; + + pr_info("version: %s\n", BEFS_VERSION); + + err = befs_init_inodecache(); + if (err) + goto unacquire_none; + + err = register_filesystem(&befs_fs_type); + if (err) + goto unacquire_inodecache; + + return 0; + +unacquire_inodecache: + befs_destroy_inodecache(); + +unacquire_none: + return err; +} + +static void __exit +exit_befs_fs(void) +{ + befs_destroy_inodecache(); + + unregister_filesystem(&befs_fs_type); +} + +/* + * Macros that typecheck the init and exit functions, + * ensures that they are called at init and cleanup, + * and eliminates warnings about unused functions. + */ +module_init(init_befs_fs) +module_exit(exit_befs_fs) diff --git a/fs/befs/super.c b/fs/befs/super.c new file mode 100644 index 000000000..7c50025c9 --- /dev/null +++ b/fs/befs/super.c @@ -0,0 +1,118 @@ +/* + * super.c + * + * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com> + * + * Licensed under the GNU GPL. See the file COPYING for details. + * + */ + +#include <linux/fs.h> +#include <asm/page.h> /* for PAGE_SIZE */ + +#include "befs.h" +#include "super.h" + +/* + * befs_load_sb -- Read from disk and properly byteswap all the fields + * of the befs superblock + */ +int +befs_load_sb(struct super_block *sb, befs_super_block *disk_sb) +{ + struct befs_sb_info *befs_sb = BEFS_SB(sb); + + /* Check the byte order of the filesystem */ + if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_LE) + befs_sb->byte_order = BEFS_BYTESEX_LE; + else if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_BE) + befs_sb->byte_order = BEFS_BYTESEX_BE; + + befs_sb->magic1 = fs32_to_cpu(sb, disk_sb->magic1); + befs_sb->magic2 = fs32_to_cpu(sb, disk_sb->magic2); + befs_sb->magic3 = fs32_to_cpu(sb, disk_sb->magic3); + befs_sb->block_size = fs32_to_cpu(sb, disk_sb->block_size); + befs_sb->block_shift = fs32_to_cpu(sb, disk_sb->block_shift); + befs_sb->num_blocks = fs64_to_cpu(sb, disk_sb->num_blocks); + befs_sb->used_blocks = fs64_to_cpu(sb, disk_sb->used_blocks); + befs_sb->inode_size = fs32_to_cpu(sb, disk_sb->inode_size); + + befs_sb->blocks_per_ag = fs32_to_cpu(sb, disk_sb->blocks_per_ag); + befs_sb->ag_shift = fs32_to_cpu(sb, disk_sb->ag_shift); + befs_sb->num_ags = fs32_to_cpu(sb, disk_sb->num_ags); + + befs_sb->flags = fs32_to_cpu(sb, disk_sb->flags); + + befs_sb->log_blocks = fsrun_to_cpu(sb, disk_sb->log_blocks); + befs_sb->log_start = fs64_to_cpu(sb, disk_sb->log_start); + befs_sb->log_end = fs64_to_cpu(sb, disk_sb->log_end); + + befs_sb->root_dir = fsrun_to_cpu(sb, disk_sb->root_dir); + befs_sb->indices = fsrun_to_cpu(sb, disk_sb->indices); + befs_sb->nls = NULL; + + return BEFS_OK; +} + +int +befs_check_sb(struct super_block *sb) +{ + struct befs_sb_info *befs_sb = BEFS_SB(sb); + + /* Check magic headers of super block */ + if ((befs_sb->magic1 != BEFS_SUPER_MAGIC1) + || (befs_sb->magic2 != BEFS_SUPER_MAGIC2) + || (befs_sb->magic3 != BEFS_SUPER_MAGIC3)) { + befs_error(sb, "invalid magic header"); + return BEFS_ERR; + } + + /* + * Check blocksize of BEFS. + * + * Blocksize of BEFS is 1024, 2048, 4096 or 8192. + */ + + if ((befs_sb->block_size != 1024) + && (befs_sb->block_size != 2048) + && (befs_sb->block_size != 4096) + && (befs_sb->block_size != 8192)) { + befs_error(sb, "invalid blocksize: %u", befs_sb->block_size); + return BEFS_ERR; + } + + if (befs_sb->block_size > PAGE_SIZE) { + befs_error(sb, "blocksize(%u) cannot be larger " + "than system pagesize(%lu)", befs_sb->block_size, + PAGE_SIZE); + return BEFS_ERR; + } + + /* + * block_shift and block_size encode the same information + * in different ways as a consistency check. + */ + + if ((1 << befs_sb->block_shift) != befs_sb->block_size) { + befs_error(sb, "block_shift disagrees with block_size. " + "Corruption likely."); + return BEFS_ERR; + } + + + /* ag_shift also encodes the same information as blocks_per_ag in a + * different way, non-fatal consistency check + */ + if ((1 << befs_sb->ag_shift) != befs_sb->blocks_per_ag) + befs_error(sb, "ag_shift disagrees with blocks_per_ag."); + + if (befs_sb->log_start != befs_sb->log_end || + befs_sb->flags == BEFS_DIRTY) { + befs_error(sb, "Filesystem not clean! There are blocks in the " + "journal. You must boot into BeOS and mount this " + "volume to make it clean."); + return BEFS_ERR; + } + + return BEFS_OK; +} diff --git a/fs/befs/super.h b/fs/befs/super.h new file mode 100644 index 000000000..ec1df30a7 --- /dev/null +++ b/fs/befs/super.h @@ -0,0 +1,6 @@ +/* + * super.h + */ + +int befs_load_sb(struct super_block *sb, befs_super_block *disk_sb); +int befs_check_sb(struct super_block *sb); |