diff options
Diffstat (limited to 'fs/adfs')
-rw-r--r-- | fs/adfs/Kconfig | 29 | ||||
-rw-r--r-- | fs/adfs/Makefile | 8 | ||||
-rw-r--r-- | fs/adfs/adfs.h | 230 | ||||
-rw-r--r-- | fs/adfs/dir.c | 457 | ||||
-rw-r--r-- | fs/adfs/dir_f.c | 324 | ||||
-rw-r--r-- | fs/adfs/dir_f.h | 61 | ||||
-rw-r--r-- | fs/adfs/dir_fplus.c | 287 | ||||
-rw-r--r-- | fs/adfs/dir_fplus.h | 42 | ||||
-rw-r--r-- | fs/adfs/file.c | 36 | ||||
-rw-r--r-- | fs/adfs/inode.c | 369 | ||||
-rw-r--r-- | fs/adfs/map.c | 407 | ||||
-rw-r--r-- | fs/adfs/super.c | 494 |
12 files changed, 2744 insertions, 0 deletions
diff --git a/fs/adfs/Kconfig b/fs/adfs/Kconfig new file mode 100644 index 0000000000..1b97058f0c --- /dev/null +++ b/fs/adfs/Kconfig @@ -0,0 +1,29 @@ +# SPDX-License-Identifier: GPL-2.0-only +config ADFS_FS + tristate "ADFS file system support" + depends on BLOCK + select BUFFER_HEAD + help + The Acorn Disc Filing System is the standard file system of the + RiscOS operating system which runs on Acorn's ARM-based Risc PC + systems and the Acorn Archimedes range of machines. If you say Y + here, Linux will be able to read from ADFS partitions on hard drives + and from ADFS-formatted floppy discs. If you also want to be able to + write to those devices, say Y to "ADFS write support" below. + + The ADFS partition should be the first partition (i.e., + /dev/[hs]d?1) on each of your drives. Please read the file + <file:Documentation/filesystems/adfs.rst> for further details. + + To compile this code as a module, choose M here: the module will be + called adfs. + + If unsure, say N. + +config ADFS_FS_RW + bool "ADFS write support (DANGEROUS)" + depends on ADFS_FS + help + If you say Y here, you will be able to write to ADFS partitions on + hard drives and ADFS-formatted floppy disks. This is experimental + codes, so if you're unsure, say N. diff --git a/fs/adfs/Makefile b/fs/adfs/Makefile new file mode 100644 index 0000000000..cf7de6ece6 --- /dev/null +++ b/fs/adfs/Makefile @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the linux adfs filesystem routines. +# + +obj-$(CONFIG_ADFS_FS) += adfs.o + +adfs-objs := dir.o dir_f.o dir_fplus.o file.o inode.o map.o super.o diff --git a/fs/adfs/adfs.h b/fs/adfs/adfs.h new file mode 100644 index 0000000000..223f0283d2 --- /dev/null +++ b/fs/adfs/adfs.h @@ -0,0 +1,230 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/buffer_head.h> +#include <linux/fs.h> +#include <linux/adfs_fs.h> + +/* Internal data structures for ADFS */ + +#define ADFS_FREE_FRAG 0 +#define ADFS_BAD_FRAG 1 +#define ADFS_ROOT_FRAG 2 + +#define ADFS_FILETYPE_NONE ((u16)~0) + +/* RISC OS 12-bit filetype is stored in load_address[19:8] */ +static inline u16 adfs_filetype(u32 loadaddr) +{ + return (loadaddr & 0xfff00000) == 0xfff00000 ? + (loadaddr >> 8) & 0xfff : ADFS_FILETYPE_NONE; +} + +#define ADFS_NDA_OWNER_READ (1 << 0) +#define ADFS_NDA_OWNER_WRITE (1 << 1) +#define ADFS_NDA_LOCKED (1 << 2) +#define ADFS_NDA_DIRECTORY (1 << 3) +#define ADFS_NDA_EXECUTE (1 << 4) +#define ADFS_NDA_PUBLIC_READ (1 << 5) +#define ADFS_NDA_PUBLIC_WRITE (1 << 6) + +/* + * adfs file system inode data in memory + */ +struct adfs_inode_info { + loff_t mmu_private; + __u32 parent_id; /* parent indirect disc address */ + __u32 indaddr; /* object indirect disc address */ + __u32 loadaddr; /* RISC OS load address */ + __u32 execaddr; /* RISC OS exec address */ + unsigned int attr; /* RISC OS permissions */ + struct inode vfs_inode; +}; + +static inline struct adfs_inode_info *ADFS_I(struct inode *inode) +{ + return container_of(inode, struct adfs_inode_info, vfs_inode); +} + +static inline bool adfs_inode_is_stamped(struct inode *inode) +{ + return (ADFS_I(inode)->loadaddr & 0xfff00000) == 0xfff00000; +} + +/* + * Forward-declare this + */ +struct adfs_discmap; +struct adfs_dir_ops; + +/* + * ADFS file system superblock data in memory + */ +struct adfs_sb_info { + union { struct { + struct adfs_discmap *s_map; /* bh list containing map */ + const struct adfs_dir_ops *s_dir; /* directory operations */ + }; + struct rcu_head rcu; /* used only at shutdown time */ + }; + kuid_t s_uid; /* owner uid */ + kgid_t s_gid; /* owner gid */ + umode_t s_owner_mask; /* ADFS owner perm -> unix perm */ + umode_t s_other_mask; /* ADFS other perm -> unix perm */ + int s_ftsuffix; /* ,xyz hex filetype suffix option */ + + __u32 s_ids_per_zone; /* max. no ids in one zone */ + __u32 s_idlen; /* length of ID in map */ + __u32 s_map_size; /* sector size of a map */ + signed int s_map2blk; /* shift left by this for map->sector*/ + unsigned int s_log2sharesize;/* log2 share size */ + unsigned int s_namelen; /* maximum number of characters in name */ +}; + +static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb) +{ + return sb->s_fs_info; +} + +/* + * Directory handling + */ +struct adfs_dir { + struct super_block *sb; + + int nr_buffers; + struct buffer_head *bh[4]; + struct buffer_head **bhs; + + unsigned int pos; + __u32 parent_id; + + union { + struct adfs_dirheader *dirhead; + struct adfs_bigdirheader *bighead; + }; + union { + struct adfs_newdirtail *newtail; + struct adfs_bigdirtail *bigtail; + }; +}; + +/* + * This is the overall maximum name length + */ +#define ADFS_MAX_NAME_LEN (256 + 4) /* +4 for ,xyz hex filetype suffix */ +struct object_info { + __u32 parent_id; /* parent object id */ + __u32 indaddr; /* indirect disc addr */ + __u32 loadaddr; /* load address */ + __u32 execaddr; /* execution address */ + __u32 size; /* size */ + __u8 attr; /* RISC OS attributes */ + unsigned int name_len; /* name length */ + char name[ADFS_MAX_NAME_LEN];/* file name */ +}; + +struct adfs_dir_ops { + int (*read)(struct super_block *sb, unsigned int indaddr, + unsigned int size, struct adfs_dir *dir); + int (*iterate)(struct adfs_dir *dir, struct dir_context *ctx); + int (*setpos)(struct adfs_dir *dir, unsigned int fpos); + int (*getnext)(struct adfs_dir *dir, struct object_info *obj); + int (*update)(struct adfs_dir *dir, struct object_info *obj); + int (*create)(struct adfs_dir *dir, struct object_info *obj); + int (*remove)(struct adfs_dir *dir, struct object_info *obj); + int (*commit)(struct adfs_dir *dir); +}; + +struct adfs_discmap { + struct buffer_head *dm_bh; + __u32 dm_startblk; + unsigned int dm_startbit; + unsigned int dm_endbit; +}; + +/* Inode stuff */ +struct inode *adfs_iget(struct super_block *sb, struct object_info *obj); +int adfs_write_inode(struct inode *inode, struct writeback_control *wbc); +int adfs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry, + struct iattr *attr); + +/* map.c */ +int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset); +void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf); +struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr); +void adfs_free_map(struct super_block *sb); + +/* Misc */ +__printf(3, 4) +void __adfs_error(struct super_block *sb, const char *function, + const char *fmt, ...); +#define adfs_error(sb, fmt...) __adfs_error(sb, __func__, fmt) +void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...); + +/* super.c */ + +/* + * Inodes and file operations + */ + +/* dir_*.c */ +extern const struct inode_operations adfs_dir_inode_operations; +extern const struct file_operations adfs_dir_operations; +extern const struct dentry_operations adfs_dentry_operations; +extern const struct adfs_dir_ops adfs_f_dir_ops; +extern const struct adfs_dir_ops adfs_fplus_dir_ops; + +int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset, + size_t len); +int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src, + size_t len); +void adfs_dir_relse(struct adfs_dir *dir); +int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir); +void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj); +extern int adfs_dir_update(struct super_block *sb, struct object_info *obj, + int wait); + +/* file.c */ +extern const struct inode_operations adfs_file_inode_operations; +extern const struct file_operations adfs_file_operations; + +static inline __u32 signed_asl(__u32 val, signed int shift) +{ + if (shift >= 0) + val <<= shift; + else + val >>= -shift; + return val; +} + +/* + * Calculate the address of a block in an object given the block offset + * and the object identity. + * + * The root directory ID should always be looked up in the map [3.4] + */ +static inline int __adfs_block_map(struct super_block *sb, u32 indaddr, + unsigned int block) +{ + if (indaddr & 255) { + unsigned int off; + + off = (indaddr & 255) - 1; + block += off << ADFS_SB(sb)->s_log2sharesize; + } + + return adfs_map_lookup(sb, indaddr >> 8, block); +} + +/* Return the disc record from the map */ +static inline +struct adfs_discrecord *adfs_map_discrecord(struct adfs_discmap *dm) +{ + return (void *)(dm[0].dm_bh->b_data + 4); +} + +static inline u64 adfs_disc_size(const struct adfs_discrecord *dr) +{ + return (u64)le32_to_cpu(dr->disc_size_high) << 32 | + le32_to_cpu(dr->disc_size); +} diff --git a/fs/adfs/dir.c b/fs/adfs/dir.c new file mode 100644 index 0000000000..77fbd19600 --- /dev/null +++ b/fs/adfs/dir.c @@ -0,0 +1,457 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/dir.c + * + * Copyright (C) 1999-2000 Russell King + * + * Common directory handling for ADFS + */ +#include <linux/slab.h> +#include "adfs.h" + +/* + * For future. This should probably be per-directory. + */ +static DECLARE_RWSEM(adfs_dir_rwsem); + +int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset, + size_t len) +{ + struct super_block *sb = dir->sb; + unsigned int index, remain; + + index = offset >> sb->s_blocksize_bits; + offset &= sb->s_blocksize - 1; + remain = sb->s_blocksize - offset; + if (index + (remain < len) >= dir->nr_buffers) + return -EINVAL; + + if (remain < len) { + memcpy(dst, dir->bhs[index]->b_data + offset, remain); + dst += remain; + len -= remain; + index += 1; + offset = 0; + } + + memcpy(dst, dir->bhs[index]->b_data + offset, len); + + return 0; +} + +int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src, + size_t len) +{ + struct super_block *sb = dir->sb; + unsigned int index, remain; + + index = offset >> sb->s_blocksize_bits; + offset &= sb->s_blocksize - 1; + remain = sb->s_blocksize - offset; + if (index + (remain < len) >= dir->nr_buffers) + return -EINVAL; + + if (remain < len) { + memcpy(dir->bhs[index]->b_data + offset, src, remain); + src += remain; + len -= remain; + index += 1; + offset = 0; + } + + memcpy(dir->bhs[index]->b_data + offset, src, len); + + return 0; +} + +static void __adfs_dir_cleanup(struct adfs_dir *dir) +{ + dir->nr_buffers = 0; + + if (dir->bhs != dir->bh) + kfree(dir->bhs); + dir->bhs = NULL; + dir->sb = NULL; +} + +void adfs_dir_relse(struct adfs_dir *dir) +{ + unsigned int i; + + for (i = 0; i < dir->nr_buffers; i++) + brelse(dir->bhs[i]); + + __adfs_dir_cleanup(dir); +} + +static void adfs_dir_forget(struct adfs_dir *dir) +{ + unsigned int i; + + for (i = 0; i < dir->nr_buffers; i++) + bforget(dir->bhs[i]); + + __adfs_dir_cleanup(dir); +} + +int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir) +{ + struct buffer_head **bhs; + unsigned int i, num; + int block; + + num = ALIGN(size, sb->s_blocksize) >> sb->s_blocksize_bits; + if (num > ARRAY_SIZE(dir->bh)) { + /* We only allow one extension */ + if (dir->bhs != dir->bh) + return -EINVAL; + + bhs = kcalloc(num, sizeof(*bhs), GFP_KERNEL); + if (!bhs) + return -ENOMEM; + + if (dir->nr_buffers) + memcpy(bhs, dir->bhs, dir->nr_buffers * sizeof(*bhs)); + + dir->bhs = bhs; + } + + for (i = dir->nr_buffers; i < num; i++) { + block = __adfs_block_map(sb, indaddr, i); + if (!block) { + adfs_error(sb, "dir %06x has a hole at offset %u", + indaddr, i); + goto error; + } + + dir->bhs[i] = sb_bread(sb, block); + if (!dir->bhs[i]) { + adfs_error(sb, + "dir %06x failed read at offset %u, mapped block 0x%08x", + indaddr, i, block); + goto error; + } + + dir->nr_buffers++; + } + return 0; + +error: + adfs_dir_relse(dir); + + return -EIO; +} + +static int adfs_dir_read(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir) +{ + dir->sb = sb; + dir->bhs = dir->bh; + dir->nr_buffers = 0; + + return ADFS_SB(sb)->s_dir->read(sb, indaddr, size, dir); +} + +static int adfs_dir_read_inode(struct super_block *sb, struct inode *inode, + struct adfs_dir *dir) +{ + int ret; + + ret = adfs_dir_read(sb, ADFS_I(inode)->indaddr, inode->i_size, dir); + if (ret) + return ret; + + if (ADFS_I(inode)->parent_id != dir->parent_id) { + adfs_error(sb, + "parent directory id changed under me! (%06x but got %06x)\n", + ADFS_I(inode)->parent_id, dir->parent_id); + adfs_dir_relse(dir); + ret = -EIO; + } + + return ret; +} + +static void adfs_dir_mark_dirty(struct adfs_dir *dir) +{ + unsigned int i; + + /* Mark the buffers dirty */ + for (i = 0; i < dir->nr_buffers; i++) + mark_buffer_dirty(dir->bhs[i]); +} + +static int adfs_dir_sync(struct adfs_dir *dir) +{ + int err = 0; + int i; + + for (i = dir->nr_buffers - 1; i >= 0; i--) { + struct buffer_head *bh = dir->bhs[i]; + sync_dirty_buffer(bh); + if (buffer_req(bh) && !buffer_uptodate(bh)) + err = -EIO; + } + + return err; +} + +void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj) +{ + unsigned int dots, i; + + /* + * RISC OS allows the use of '/' in directory entry names, so we need + * to fix these up. '/' is typically used for FAT compatibility to + * represent '.', so do the same conversion here. In any case, '.' + * will never be in a RISC OS name since it is used as the pathname + * separator. Handle the case where we may generate a '.' or '..' + * name, replacing the first character with '^' (the RISC OS "parent + * directory" character.) + */ + for (i = dots = 0; i < obj->name_len; i++) + if (obj->name[i] == '/') { + obj->name[i] = '.'; + dots++; + } + + if (obj->name_len <= 2 && dots == obj->name_len) + obj->name[0] = '^'; + + /* + * If the object is a file, and the user requested the ,xyz hex + * filetype suffix to the name, check the filetype and append. + */ + if (!(obj->attr & ADFS_NDA_DIRECTORY) && ADFS_SB(dir->sb)->s_ftsuffix) { + u16 filetype = adfs_filetype(obj->loadaddr); + + if (filetype != ADFS_FILETYPE_NONE) { + obj->name[obj->name_len++] = ','; + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 8); + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 4); + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 0); + } + } +} + +static int adfs_iterate(struct file *file, struct dir_context *ctx) +{ + struct inode *inode = file_inode(file); + struct super_block *sb = inode->i_sb; + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + struct adfs_dir dir; + int ret; + + down_read(&adfs_dir_rwsem); + ret = adfs_dir_read_inode(sb, inode, &dir); + if (ret) + goto unlock; + + if (ctx->pos == 0) { + if (!dir_emit_dot(file, ctx)) + goto unlock_relse; + ctx->pos = 1; + } + if (ctx->pos == 1) { + if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR)) + goto unlock_relse; + ctx->pos = 2; + } + + ret = ops->iterate(&dir, ctx); + +unlock_relse: + up_read(&adfs_dir_rwsem); + adfs_dir_relse(&dir); + return ret; + +unlock: + up_read(&adfs_dir_rwsem); + return ret; +} + +int +adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait) +{ + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + struct adfs_dir dir; + int ret; + + if (!IS_ENABLED(CONFIG_ADFS_FS_RW)) + return -EINVAL; + + if (!ops->update) + return -EINVAL; + + down_write(&adfs_dir_rwsem); + ret = adfs_dir_read(sb, obj->parent_id, 0, &dir); + if (ret) + goto unlock; + + ret = ops->update(&dir, obj); + if (ret) + goto forget; + + ret = ops->commit(&dir); + if (ret) + goto forget; + up_write(&adfs_dir_rwsem); + + adfs_dir_mark_dirty(&dir); + + if (wait) + ret = adfs_dir_sync(&dir); + + adfs_dir_relse(&dir); + return ret; + + /* + * If the updated failed because the entry wasn't found, we can + * just release the buffers. If it was any other error, forget + * the dirtied buffers so they aren't written back to the media. + */ +forget: + if (ret == -ENOENT) + adfs_dir_relse(&dir); + else + adfs_dir_forget(&dir); +unlock: + up_write(&adfs_dir_rwsem); + + return ret; +} + +static unsigned char adfs_tolower(unsigned char c) +{ + if (c >= 'A' && c <= 'Z') + c += 'a' - 'A'; + return c; +} + +static int __adfs_compare(const unsigned char *qstr, u32 qlen, + const char *str, u32 len) +{ + u32 i; + + if (qlen != len) + return 1; + + for (i = 0; i < qlen; i++) + if (adfs_tolower(qstr[i]) != adfs_tolower(str[i])) + return 1; + + return 0; +} + +static int adfs_dir_lookup_byname(struct inode *inode, const struct qstr *qstr, + struct object_info *obj) +{ + struct super_block *sb = inode->i_sb; + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + const unsigned char *name; + struct adfs_dir dir; + u32 name_len; + int ret; + + down_read(&adfs_dir_rwsem); + ret = adfs_dir_read_inode(sb, inode, &dir); + if (ret) + goto unlock; + + ret = ops->setpos(&dir, 0); + if (ret) + goto unlock_relse; + + ret = -ENOENT; + name = qstr->name; + name_len = qstr->len; + while (ops->getnext(&dir, obj) == 0) { + if (!__adfs_compare(name, name_len, obj->name, obj->name_len)) { + ret = 0; + break; + } + } + obj->parent_id = ADFS_I(inode)->indaddr; + +unlock_relse: + up_read(&adfs_dir_rwsem); + adfs_dir_relse(&dir); + return ret; + +unlock: + up_read(&adfs_dir_rwsem); + return ret; +} + +const struct file_operations adfs_dir_operations = { + .read = generic_read_dir, + .llseek = generic_file_llseek, + .iterate_shared = adfs_iterate, + .fsync = generic_file_fsync, +}; + +static int +adfs_hash(const struct dentry *parent, struct qstr *qstr) +{ + const unsigned char *name; + unsigned long hash; + u32 len; + + if (qstr->len > ADFS_SB(parent->d_sb)->s_namelen) + return -ENAMETOOLONG; + + len = qstr->len; + name = qstr->name; + hash = init_name_hash(parent); + while (len--) + hash = partial_name_hash(adfs_tolower(*name++), hash); + qstr->hash = end_name_hash(hash); + + return 0; +} + +/* + * Compare two names, taking note of the name length + * requirements of the underlying filesystem. + */ +static int adfs_compare(const struct dentry *dentry, unsigned int len, + const char *str, const struct qstr *qstr) +{ + return __adfs_compare(qstr->name, qstr->len, str, len); +} + +const struct dentry_operations adfs_dentry_operations = { + .d_hash = adfs_hash, + .d_compare = adfs_compare, +}; + +static struct dentry * +adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) +{ + struct inode *inode = NULL; + struct object_info obj; + int error; + + error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj); + if (error == 0) { + /* + * This only returns NULL if get_empty_inode + * fails. + */ + inode = adfs_iget(dir->i_sb, &obj); + if (!inode) + inode = ERR_PTR(-EACCES); + } else if (error != -ENOENT) { + inode = ERR_PTR(error); + } + return d_splice_alias(inode, dentry); +} + +/* + * directories can handle most operations... + */ +const struct inode_operations adfs_dir_inode_operations = { + .lookup = adfs_lookup, + .setattr = adfs_notify_change, +}; diff --git a/fs/adfs/dir_f.c b/fs/adfs/dir_f.c new file mode 100644 index 0000000000..05e963402e --- /dev/null +++ b/fs/adfs/dir_f.c @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/dir_f.c + * + * Copyright (C) 1997-1999 Russell King + * + * E and F format directory handling + */ +#include "adfs.h" +#include "dir_f.h" + +/* + * Read an (unaligned) value of length 1..4 bytes + */ +static inline unsigned int adfs_readval(unsigned char *p, int len) +{ + unsigned int val = 0; + + switch (len) { + case 4: val |= p[3] << 24; + fallthrough; + case 3: val |= p[2] << 16; + fallthrough; + case 2: val |= p[1] << 8; + fallthrough; + default: val |= p[0]; + } + return val; +} + +static inline void adfs_writeval(unsigned char *p, int len, unsigned int val) +{ + switch (len) { + case 4: p[3] = val >> 24; + fallthrough; + case 3: p[2] = val >> 16; + fallthrough; + case 2: p[1] = val >> 8; + fallthrough; + default: p[0] = val; + } +} + +#define ror13(v) ((v >> 13) | (v << 19)) + +#define dir_u8(idx) \ + ({ int _buf = idx >> blocksize_bits; \ + int _off = idx - (_buf << blocksize_bits);\ + *(u8 *)(bh[_buf]->b_data + _off); \ + }) + +#define dir_u32(idx) \ + ({ int _buf = idx >> blocksize_bits; \ + int _off = idx - (_buf << blocksize_bits);\ + *(__le32 *)(bh[_buf]->b_data + _off); \ + }) + +#define bufoff(_bh,_idx) \ + ({ int _buf = _idx >> blocksize_bits; \ + int _off = _idx - (_buf << blocksize_bits);\ + (void *)(_bh[_buf]->b_data + _off); \ + }) + +/* + * There are some algorithms that are nice in + * assembler, but a bitch in C... This is one + * of them. + */ +static u8 +adfs_dir_checkbyte(const struct adfs_dir *dir) +{ + struct buffer_head * const *bh = dir->bh; + const int blocksize_bits = dir->sb->s_blocksize_bits; + union { __le32 *ptr32; u8 *ptr8; } ptr, end; + u32 dircheck = 0; + int last = 5 - 26; + int i = 0; + + /* + * Accumulate each word up to the last whole + * word of the last directory entry. This + * can spread across several buffer heads. + */ + do { + last += 26; + do { + dircheck = le32_to_cpu(dir_u32(i)) ^ ror13(dircheck); + + i += sizeof(u32); + } while (i < (last & ~3)); + } while (dir_u8(last) != 0); + + /* + * Accumulate the last few bytes. These + * bytes will be within the same bh. + */ + if (i != last) { + ptr.ptr8 = bufoff(bh, i); + end.ptr8 = ptr.ptr8 + last - i; + + do { + dircheck = *ptr.ptr8++ ^ ror13(dircheck); + } while (ptr.ptr8 < end.ptr8); + } + + /* + * The directory tail is in the final bh + * Note that contary to the RISC OS PRMs, + * the first few bytes are NOT included + * in the check. All bytes are in the + * same bh. + */ + ptr.ptr8 = bufoff(bh, 2008); + end.ptr8 = ptr.ptr8 + 36; + + do { + __le32 v = *ptr.ptr32++; + dircheck = le32_to_cpu(v) ^ ror13(dircheck); + } while (ptr.ptr32 < end.ptr32); + + return (dircheck ^ (dircheck >> 8) ^ (dircheck >> 16) ^ (dircheck >> 24)) & 0xff; +} + +static int adfs_f_validate(struct adfs_dir *dir) +{ + struct adfs_dirheader *head = dir->dirhead; + struct adfs_newdirtail *tail = dir->newtail; + + if (head->startmasseq != tail->endmasseq || + tail->dirlastmask || tail->reserved[0] || tail->reserved[1] || + (memcmp(&head->startname, "Nick", 4) && + memcmp(&head->startname, "Hugo", 4)) || + memcmp(&head->startname, &tail->endname, 4) || + adfs_dir_checkbyte(dir) != tail->dircheckbyte) + return -EIO; + + return 0; +} + +/* Read and check that a directory is valid */ +static int adfs_f_read(struct super_block *sb, u32 indaddr, unsigned int size, + struct adfs_dir *dir) +{ + const unsigned int blocksize_bits = sb->s_blocksize_bits; + int ret; + + if (size && size != ADFS_NEWDIR_SIZE) + return -EIO; + + ret = adfs_dir_read_buffers(sb, indaddr, ADFS_NEWDIR_SIZE, dir); + if (ret) + return ret; + + dir->dirhead = bufoff(dir->bh, 0); + dir->newtail = bufoff(dir->bh, 2007); + + if (adfs_f_validate(dir)) + goto bad_dir; + + dir->parent_id = adfs_readval(dir->newtail->dirparent, 3); + + return 0; + +bad_dir: + adfs_error(sb, "dir %06x is corrupted", indaddr); + adfs_dir_relse(dir); + + return -EIO; +} + +/* + * convert a disk-based directory entry to a Linux ADFS directory entry + */ +static inline void +adfs_dir2obj(struct adfs_dir *dir, struct object_info *obj, + struct adfs_direntry *de) +{ + unsigned int name_len; + + for (name_len = 0; name_len < ADFS_F_NAME_LEN; name_len++) { + if (de->dirobname[name_len] < ' ') + break; + + obj->name[name_len] = de->dirobname[name_len]; + } + + obj->name_len = name_len; + obj->indaddr = adfs_readval(de->dirinddiscadd, 3); + obj->loadaddr = adfs_readval(de->dirload, 4); + obj->execaddr = adfs_readval(de->direxec, 4); + obj->size = adfs_readval(de->dirlen, 4); + obj->attr = de->newdiratts; + + adfs_object_fixup(dir, obj); +} + +/* + * convert a Linux ADFS directory entry to a disk-based directory entry + */ +static inline void +adfs_obj2dir(struct adfs_direntry *de, struct object_info *obj) +{ + adfs_writeval(de->dirinddiscadd, 3, obj->indaddr); + adfs_writeval(de->dirload, 4, obj->loadaddr); + adfs_writeval(de->direxec, 4, obj->execaddr); + adfs_writeval(de->dirlen, 4, obj->size); + de->newdiratts = obj->attr; +} + +/* + * get a directory entry. Note that the caller is responsible + * for holding the relevant locks. + */ +static int +__adfs_dir_get(struct adfs_dir *dir, int pos, struct object_info *obj) +{ + struct adfs_direntry de; + int ret; + + ret = adfs_dir_copyfrom(&de, dir, pos, 26); + if (ret) + return ret; + + if (!de.dirobname[0]) + return -ENOENT; + + adfs_dir2obj(dir, obj, &de); + + return 0; +} + +static int +adfs_f_setpos(struct adfs_dir *dir, unsigned int fpos) +{ + if (fpos >= ADFS_NUM_DIR_ENTRIES) + return -ENOENT; + + dir->pos = 5 + fpos * 26; + return 0; +} + +static int +adfs_f_getnext(struct adfs_dir *dir, struct object_info *obj) +{ + unsigned int ret; + + ret = __adfs_dir_get(dir, dir->pos, obj); + if (ret == 0) + dir->pos += 26; + + return ret; +} + +static int adfs_f_iterate(struct adfs_dir *dir, struct dir_context *ctx) +{ + struct object_info obj; + int pos = 5 + (ctx->pos - 2) * 26; + + while (ctx->pos < 2 + ADFS_NUM_DIR_ENTRIES) { + if (__adfs_dir_get(dir, pos, &obj)) + break; + if (!dir_emit(ctx, obj.name, obj.name_len, + obj.indaddr, DT_UNKNOWN)) + break; + pos += 26; + ctx->pos++; + } + return 0; +} + +static int adfs_f_update(struct adfs_dir *dir, struct object_info *obj) +{ + struct adfs_direntry de; + int offset, ret; + + offset = 5 - (int)sizeof(de); + + do { + offset += sizeof(de); + ret = adfs_dir_copyfrom(&de, dir, offset, sizeof(de)); + if (ret) { + adfs_error(dir->sb, "error reading directory entry"); + return -ENOENT; + } + if (!de.dirobname[0]) { + adfs_error(dir->sb, "unable to locate entry to update"); + return -ENOENT; + } + } while (adfs_readval(de.dirinddiscadd, 3) != obj->indaddr); + + /* Update the directory entry with the new object state */ + adfs_obj2dir(&de, obj); + + /* Write the directory entry back to the directory */ + return adfs_dir_copyto(dir, offset, &de, 26); +} + +static int adfs_f_commit(struct adfs_dir *dir) +{ + int ret; + + /* Increment directory sequence number */ + dir->dirhead->startmasseq += 1; + dir->newtail->endmasseq += 1; + + /* Update directory check byte */ + dir->newtail->dircheckbyte = adfs_dir_checkbyte(dir); + + /* Make sure the directory still validates correctly */ + ret = adfs_f_validate(dir); + if (ret) + adfs_msg(dir->sb, KERN_ERR, "error: update broke directory"); + + return ret; +} + +const struct adfs_dir_ops adfs_f_dir_ops = { + .read = adfs_f_read, + .iterate = adfs_f_iterate, + .setpos = adfs_f_setpos, + .getnext = adfs_f_getnext, + .update = adfs_f_update, + .commit = adfs_f_commit, +}; diff --git a/fs/adfs/dir_f.h b/fs/adfs/dir_f.h new file mode 100644 index 0000000000..4e6c53d59e --- /dev/null +++ b/fs/adfs/dir_f.h @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/fs/adfs/dir_f.h + * + * Copyright (C) 1999 Russell King + * + * Structures of directories on the F format disk + */ +#ifndef ADFS_DIR_F_H +#define ADFS_DIR_F_H + +/* + * Directory header + */ +struct adfs_dirheader { + __u8 startmasseq; + __u8 startname[4]; +} __attribute__((packed)); + +#define ADFS_NEWDIR_SIZE 2048 +#define ADFS_NUM_DIR_ENTRIES 77 + +/* + * Directory entries + */ +struct adfs_direntry { +#define ADFS_F_NAME_LEN 10 + char dirobname[ADFS_F_NAME_LEN]; + __u8 dirload[4]; + __u8 direxec[4]; + __u8 dirlen[4]; + __u8 dirinddiscadd[3]; + __u8 newdiratts; +} __attribute__((packed)); + +/* + * Directory tail + */ +struct adfs_olddirtail { + __u8 dirlastmask; + char dirname[10]; + __u8 dirparent[3]; + char dirtitle[19]; + __u8 reserved[14]; + __u8 endmasseq; + __u8 endname[4]; + __u8 dircheckbyte; +} __attribute__((packed)); + +struct adfs_newdirtail { + __u8 dirlastmask; + __u8 reserved[2]; + __u8 dirparent[3]; + char dirtitle[19]; + char dirname[10]; + __u8 endmasseq; + __u8 endname[4]; + __u8 dircheckbyte; +} __attribute__((packed)); + +#endif diff --git a/fs/adfs/dir_fplus.c b/fs/adfs/dir_fplus.c new file mode 100644 index 0000000000..4a15924014 --- /dev/null +++ b/fs/adfs/dir_fplus.c @@ -0,0 +1,287 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/dir_fplus.c + * + * Copyright (C) 1997-1999 Russell King + */ +#include "adfs.h" +#include "dir_fplus.h" + +/* Return the byte offset to directory entry pos */ +static unsigned int adfs_fplus_offset(const struct adfs_bigdirheader *h, + unsigned int pos) +{ + return offsetof(struct adfs_bigdirheader, bigdirname) + + ALIGN(le32_to_cpu(h->bigdirnamelen), 4) + + pos * sizeof(struct adfs_bigdirentry); +} + +static int adfs_fplus_validate_header(const struct adfs_bigdirheader *h) +{ + unsigned int size = le32_to_cpu(h->bigdirsize); + unsigned int len; + + if (h->bigdirversion[0] != 0 || h->bigdirversion[1] != 0 || + h->bigdirversion[2] != 0 || + h->bigdirstartname != cpu_to_le32(BIGDIRSTARTNAME) || + !size || size & 2047 || size > SZ_4M) + return -EIO; + + size -= sizeof(struct adfs_bigdirtail) + + offsetof(struct adfs_bigdirheader, bigdirname); + + /* Check that bigdirnamelen fits within the directory */ + len = ALIGN(le32_to_cpu(h->bigdirnamelen), 4); + if (len > size) + return -EIO; + + size -= len; + + /* Check that bigdirnamesize fits within the directory */ + len = le32_to_cpu(h->bigdirnamesize); + if (len > size) + return -EIO; + + size -= len; + + /* + * Avoid division, we know that absolute maximum number of entries + * can not be so large to cause overflow of the multiplication below. + */ + len = le32_to_cpu(h->bigdirentries); + if (len > SZ_4M / sizeof(struct adfs_bigdirentry) || + len * sizeof(struct adfs_bigdirentry) > size) + return -EIO; + + return 0; +} + +static int adfs_fplus_validate_tail(const struct adfs_bigdirheader *h, + const struct adfs_bigdirtail *t) +{ + if (t->bigdirendname != cpu_to_le32(BIGDIRENDNAME) || + t->bigdirendmasseq != h->startmasseq || + t->reserved[0] != 0 || t->reserved[1] != 0) + return -EIO; + + return 0; +} + +static u8 adfs_fplus_checkbyte(struct adfs_dir *dir) +{ + struct adfs_bigdirheader *h = dir->bighead; + struct adfs_bigdirtail *t = dir->bigtail; + unsigned int end, bs, bi, i; + __le32 *bp; + u32 dircheck; + + end = adfs_fplus_offset(h, le32_to_cpu(h->bigdirentries)) + + le32_to_cpu(h->bigdirnamesize); + + /* Accumulate the contents of the header, entries and names */ + for (dircheck = 0, bi = 0; end; bi++) { + bp = (void *)dir->bhs[bi]->b_data; + bs = dir->bhs[bi]->b_size; + if (bs > end) + bs = end; + + for (i = 0; i < bs; i += sizeof(u32)) + dircheck = ror32(dircheck, 13) ^ le32_to_cpup(bp++); + + end -= bs; + } + + /* Accumulate the contents of the tail except for the check byte */ + dircheck = ror32(dircheck, 13) ^ le32_to_cpu(t->bigdirendname); + dircheck = ror32(dircheck, 13) ^ t->bigdirendmasseq; + dircheck = ror32(dircheck, 13) ^ t->reserved[0]; + dircheck = ror32(dircheck, 13) ^ t->reserved[1]; + + return dircheck ^ dircheck >> 8 ^ dircheck >> 16 ^ dircheck >> 24; +} + +static int adfs_fplus_read(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir) +{ + struct adfs_bigdirheader *h; + struct adfs_bigdirtail *t; + unsigned int dirsize; + int ret; + + /* Read first buffer */ + ret = adfs_dir_read_buffers(sb, indaddr, sb->s_blocksize, dir); + if (ret) + return ret; + + dir->bighead = h = (void *)dir->bhs[0]->b_data; + ret = adfs_fplus_validate_header(h); + if (ret) { + adfs_error(sb, "dir %06x has malformed header", indaddr); + goto out; + } + + dirsize = le32_to_cpu(h->bigdirsize); + if (size && dirsize != size) { + adfs_msg(sb, KERN_WARNING, + "dir %06x header size %X does not match directory size %X", + indaddr, dirsize, size); + } + + /* Read remaining buffers */ + ret = adfs_dir_read_buffers(sb, indaddr, dirsize, dir); + if (ret) + return ret; + + dir->bigtail = t = (struct adfs_bigdirtail *) + (dir->bhs[dir->nr_buffers - 1]->b_data + (sb->s_blocksize - 8)); + + ret = adfs_fplus_validate_tail(h, t); + if (ret) { + adfs_error(sb, "dir %06x has malformed tail", indaddr); + goto out; + } + + if (adfs_fplus_checkbyte(dir) != t->bigdircheckbyte) { + adfs_error(sb, "dir %06x checkbyte mismatch\n", indaddr); + goto out; + } + + dir->parent_id = le32_to_cpu(h->bigdirparent); + return 0; + +out: + adfs_dir_relse(dir); + + return ret; +} + +static int +adfs_fplus_setpos(struct adfs_dir *dir, unsigned int fpos) +{ + int ret = -ENOENT; + + if (fpos <= le32_to_cpu(dir->bighead->bigdirentries)) { + dir->pos = fpos; + ret = 0; + } + + return ret; +} + +static int +adfs_fplus_getnext(struct adfs_dir *dir, struct object_info *obj) +{ + struct adfs_bigdirheader *h = dir->bighead; + struct adfs_bigdirentry bde; + unsigned int offset; + int ret; + + if (dir->pos >= le32_to_cpu(h->bigdirentries)) + return -ENOENT; + + offset = adfs_fplus_offset(h, dir->pos); + + ret = adfs_dir_copyfrom(&bde, dir, offset, + sizeof(struct adfs_bigdirentry)); + if (ret) + return ret; + + obj->loadaddr = le32_to_cpu(bde.bigdirload); + obj->execaddr = le32_to_cpu(bde.bigdirexec); + obj->size = le32_to_cpu(bde.bigdirlen); + obj->indaddr = le32_to_cpu(bde.bigdirindaddr); + obj->attr = le32_to_cpu(bde.bigdirattr); + obj->name_len = le32_to_cpu(bde.bigdirobnamelen); + + offset = adfs_fplus_offset(h, le32_to_cpu(h->bigdirentries)); + offset += le32_to_cpu(bde.bigdirobnameptr); + + ret = adfs_dir_copyfrom(obj->name, dir, offset, obj->name_len); + if (ret) + return ret; + + adfs_object_fixup(dir, obj); + + dir->pos += 1; + + return 0; +} + +static int adfs_fplus_iterate(struct adfs_dir *dir, struct dir_context *ctx) +{ + struct object_info obj; + + if ((ctx->pos - 2) >> 32) + return 0; + + if (adfs_fplus_setpos(dir, ctx->pos - 2)) + return 0; + + while (!adfs_fplus_getnext(dir, &obj)) { + if (!dir_emit(ctx, obj.name, obj.name_len, + obj.indaddr, DT_UNKNOWN)) + break; + ctx->pos++; + } + + return 0; +} + +static int adfs_fplus_update(struct adfs_dir *dir, struct object_info *obj) +{ + struct adfs_bigdirheader *h = dir->bighead; + struct adfs_bigdirentry bde; + int offset, end, ret; + + offset = adfs_fplus_offset(h, 0) - sizeof(bde); + end = adfs_fplus_offset(h, le32_to_cpu(h->bigdirentries)); + + do { + offset += sizeof(bde); + if (offset >= end) { + adfs_error(dir->sb, "unable to locate entry to update"); + return -ENOENT; + } + ret = adfs_dir_copyfrom(&bde, dir, offset, sizeof(bde)); + if (ret) { + adfs_error(dir->sb, "error reading directory entry"); + return -ENOENT; + } + } while (le32_to_cpu(bde.bigdirindaddr) != obj->indaddr); + + bde.bigdirload = cpu_to_le32(obj->loadaddr); + bde.bigdirexec = cpu_to_le32(obj->execaddr); + bde.bigdirlen = cpu_to_le32(obj->size); + bde.bigdirindaddr = cpu_to_le32(obj->indaddr); + bde.bigdirattr = cpu_to_le32(obj->attr); + + return adfs_dir_copyto(dir, offset, &bde, sizeof(bde)); +} + +static int adfs_fplus_commit(struct adfs_dir *dir) +{ + int ret; + + /* Increment directory sequence number */ + dir->bighead->startmasseq += 1; + dir->bigtail->bigdirendmasseq += 1; + + /* Update directory check byte */ + dir->bigtail->bigdircheckbyte = adfs_fplus_checkbyte(dir); + + /* Make sure the directory still validates correctly */ + ret = adfs_fplus_validate_header(dir->bighead); + if (ret == 0) + ret = adfs_fplus_validate_tail(dir->bighead, dir->bigtail); + + return ret; +} + +const struct adfs_dir_ops adfs_fplus_dir_ops = { + .read = adfs_fplus_read, + .iterate = adfs_fplus_iterate, + .setpos = adfs_fplus_setpos, + .getnext = adfs_fplus_getnext, + .update = adfs_fplus_update, + .commit = adfs_fplus_commit, +}; diff --git a/fs/adfs/dir_fplus.h b/fs/adfs/dir_fplus.h new file mode 100644 index 0000000000..d729b1591e --- /dev/null +++ b/fs/adfs/dir_fplus.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/fs/adfs/dir_fplus.h + * + * Copyright (C) 1999 Russell King + * + * Structures of directories on the F+ format disk + */ + +#define ADFS_FPLUS_NAME_LEN 255 + +#define BIGDIRSTARTNAME ('S' | 'B' << 8 | 'P' << 16 | 'r' << 24) +#define BIGDIRENDNAME ('o' | 'v' << 8 | 'e' << 16 | 'n' << 24) + +struct adfs_bigdirheader { + __u8 startmasseq; + __u8 bigdirversion[3]; + __le32 bigdirstartname; + __le32 bigdirnamelen; + __le32 bigdirsize; + __le32 bigdirentries; + __le32 bigdirnamesize; + __le32 bigdirparent; + char bigdirname[1]; +} __attribute__((packed, aligned(4))); + +struct adfs_bigdirentry { + __le32 bigdirload; + __le32 bigdirexec; + __le32 bigdirlen; + __le32 bigdirindaddr; + __le32 bigdirattr; + __le32 bigdirobnamelen; + __le32 bigdirobnameptr; +} __attribute__((packed, aligned(4))); + +struct adfs_bigdirtail { + __le32 bigdirendname; + __u8 bigdirendmasseq; + __u8 reserved[2]; + __u8 bigdircheckbyte; +} __attribute__((packed, aligned(4))); diff --git a/fs/adfs/file.c b/fs/adfs/file.c new file mode 100644 index 0000000000..ee80718aae --- /dev/null +++ b/fs/adfs/file.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/adfs/file.c + * + * Copyright (C) 1997-1999 Russell King + * from: + * + * linux/fs/ext2/file.c + * + * Copyright (C) 1992, 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + * + * from + * + * linux/fs/minix/file.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * adfs regular file handling primitives + */ +#include "adfs.h" + +const struct file_operations adfs_file_operations = { + .llseek = generic_file_llseek, + .read_iter = generic_file_read_iter, + .mmap = generic_file_mmap, + .fsync = generic_file_fsync, + .write_iter = generic_file_write_iter, + .splice_read = filemap_splice_read, +}; + +const struct inode_operations adfs_file_inode_operations = { + .setattr = adfs_notify_change, +}; diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c new file mode 100644 index 0000000000..2096300257 --- /dev/null +++ b/fs/adfs/inode.c @@ -0,0 +1,369 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/inode.c + * + * Copyright (C) 1997-1999 Russell King + */ +#include <linux/buffer_head.h> +#include <linux/writeback.h> +#include "adfs.h" + +/* + * Lookup/Create a block at offset 'block' into 'inode'. We currently do + * not support creation of new blocks, so we return -EIO for this case. + */ +static int +adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh, + int create) +{ + if (!create) { + if (block >= inode->i_blocks) + goto abort_toobig; + + block = __adfs_block_map(inode->i_sb, ADFS_I(inode)->indaddr, + block); + if (block) + map_bh(bh, inode->i_sb, block); + return 0; + } + /* don't support allocation of blocks yet */ + return -EIO; + +abort_toobig: + return 0; +} + +static int adfs_writepage(struct page *page, struct writeback_control *wbc) +{ + return block_write_full_page(page, adfs_get_block, wbc); +} + +static int adfs_read_folio(struct file *file, struct folio *folio) +{ + return block_read_full_folio(folio, adfs_get_block); +} + +static void adfs_write_failed(struct address_space *mapping, loff_t to) +{ + struct inode *inode = mapping->host; + + if (to > inode->i_size) + truncate_pagecache(inode, inode->i_size); +} + +static int adfs_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, + struct page **pagep, void **fsdata) +{ + int ret; + + *pagep = NULL; + ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata, + adfs_get_block, + &ADFS_I(mapping->host)->mmu_private); + if (unlikely(ret)) + adfs_write_failed(mapping, pos + len); + + return ret; +} + +static sector_t _adfs_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping, block, adfs_get_block); +} + +static const struct address_space_operations adfs_aops = { + .dirty_folio = block_dirty_folio, + .invalidate_folio = block_invalidate_folio, + .read_folio = adfs_read_folio, + .writepage = adfs_writepage, + .write_begin = adfs_write_begin, + .write_end = generic_write_end, + .bmap = _adfs_bmap +}; + +/* + * Convert ADFS attributes and filetype to Linux permission. + */ +static umode_t +adfs_atts2mode(struct super_block *sb, struct inode *inode) +{ + unsigned int attr = ADFS_I(inode)->attr; + umode_t mode, rmask; + struct adfs_sb_info *asb = ADFS_SB(sb); + + if (attr & ADFS_NDA_DIRECTORY) { + mode = S_IRUGO & asb->s_owner_mask; + return S_IFDIR | S_IXUGO | mode; + } + + switch (adfs_filetype(ADFS_I(inode)->loadaddr)) { + case 0xfc0: /* LinkFS */ + return S_IFLNK|S_IRWXUGO; + + case 0xfe6: /* UnixExec */ + rmask = S_IRUGO | S_IXUGO; + break; + + default: + rmask = S_IRUGO; + } + + mode = S_IFREG; + + if (attr & ADFS_NDA_OWNER_READ) + mode |= rmask & asb->s_owner_mask; + + if (attr & ADFS_NDA_OWNER_WRITE) + mode |= S_IWUGO & asb->s_owner_mask; + + if (attr & ADFS_NDA_PUBLIC_READ) + mode |= rmask & asb->s_other_mask; + + if (attr & ADFS_NDA_PUBLIC_WRITE) + mode |= S_IWUGO & asb->s_other_mask; + return mode; +} + +/* + * Convert Linux permission to ADFS attribute. We try to do the reverse + * of atts2mode, but there is not a 1:1 translation. + */ +static int adfs_mode2atts(struct super_block *sb, struct inode *inode, + umode_t ia_mode) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + umode_t mode; + int attr; + + /* FIXME: should we be able to alter a link? */ + if (S_ISLNK(inode->i_mode)) + return ADFS_I(inode)->attr; + + /* Directories do not have read/write permissions on the media */ + if (S_ISDIR(inode->i_mode)) + return ADFS_NDA_DIRECTORY; + + attr = 0; + mode = ia_mode & asb->s_owner_mask; + if (mode & S_IRUGO) + attr |= ADFS_NDA_OWNER_READ; + if (mode & S_IWUGO) + attr |= ADFS_NDA_OWNER_WRITE; + + mode = ia_mode & asb->s_other_mask; + mode &= ~asb->s_owner_mask; + if (mode & S_IRUGO) + attr |= ADFS_NDA_PUBLIC_READ; + if (mode & S_IWUGO) + attr |= ADFS_NDA_PUBLIC_WRITE; + + return attr; +} + +static const s64 nsec_unix_epoch_diff_risc_os_epoch = 2208988800000000000LL; + +/* + * Convert an ADFS time to Unix time. ADFS has a 40-bit centi-second time + * referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds + * of time to convert from RISC OS epoch to Unix epoch. + */ +static void +adfs_adfs2unix_time(struct timespec64 *tv, struct inode *inode) +{ + unsigned int high, low; + /* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since + * 01 Jan 1900 00:00:00 (RISC OS epoch) + */ + s64 nsec; + + if (!adfs_inode_is_stamped(inode)) + goto cur_time; + + high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */ + low = ADFS_I(inode)->execaddr; /* bottom 32 bits of timestamp */ + + /* convert 40-bit centi-seconds to 32-bit seconds + * going via nanoseconds to retain precision + */ + nsec = (((s64) high << 32) | (s64) low) * 10000000; /* cs to ns */ + + /* Files dated pre 01 Jan 1970 00:00:00. */ + if (nsec < nsec_unix_epoch_diff_risc_os_epoch) + goto too_early; + + /* convert from RISC OS to Unix epoch */ + nsec -= nsec_unix_epoch_diff_risc_os_epoch; + + *tv = ns_to_timespec64(nsec); + return; + + cur_time: + *tv = current_time(inode); + return; + + too_early: + tv->tv_sec = tv->tv_nsec = 0; + return; +} + +/* Convert an Unix time to ADFS time for an entry that is already stamped. */ +static void adfs_unix2adfs_time(struct inode *inode, + const struct timespec64 *ts) +{ + s64 cs, nsec = timespec64_to_ns(ts); + + /* convert from Unix to RISC OS epoch */ + nsec += nsec_unix_epoch_diff_risc_os_epoch; + + /* convert from nanoseconds to centiseconds */ + cs = div_s64(nsec, 10000000); + + cs = clamp_t(s64, cs, 0, 0xffffffffff); + + ADFS_I(inode)->loadaddr &= ~0xff; + ADFS_I(inode)->loadaddr |= (cs >> 32) & 0xff; + ADFS_I(inode)->execaddr = cs; +} + +/* + * Fill in the inode information from the object information. + * + * Note that this is an inode-less filesystem, so we can't use the inode + * number to reference the metadata on the media. Instead, we use the + * inode number to hold the object ID, which in turn will tell us where + * the data is held. We also save the parent object ID, and with these + * two, we can locate the metadata. + * + * This does mean that we rely on an objects parent remaining the same at + * all times - we cannot cope with a cross-directory rename (yet). + */ +struct inode * +adfs_iget(struct super_block *sb, struct object_info *obj) +{ + struct inode *inode; + + inode = new_inode(sb); + if (!inode) + goto out; + + inode->i_uid = ADFS_SB(sb)->s_uid; + inode->i_gid = ADFS_SB(sb)->s_gid; + inode->i_ino = obj->indaddr; + inode->i_size = obj->size; + set_nlink(inode, 2); + inode->i_blocks = (inode->i_size + sb->s_blocksize - 1) >> + sb->s_blocksize_bits; + + /* + * we need to save the parent directory ID so that + * write_inode can update the directory information + * for this file. This will need special handling + * for cross-directory renames. + */ + ADFS_I(inode)->parent_id = obj->parent_id; + ADFS_I(inode)->indaddr = obj->indaddr; + ADFS_I(inode)->loadaddr = obj->loadaddr; + ADFS_I(inode)->execaddr = obj->execaddr; + ADFS_I(inode)->attr = obj->attr; + + inode->i_mode = adfs_atts2mode(sb, inode); + adfs_adfs2unix_time(&inode->i_mtime, inode); + inode->i_atime = inode->i_mtime; + inode_set_ctime_to_ts(inode, inode->i_mtime); + + if (S_ISDIR(inode->i_mode)) { + inode->i_op = &adfs_dir_inode_operations; + inode->i_fop = &adfs_dir_operations; + } else if (S_ISREG(inode->i_mode)) { + inode->i_op = &adfs_file_inode_operations; + inode->i_fop = &adfs_file_operations; + inode->i_mapping->a_ops = &adfs_aops; + ADFS_I(inode)->mmu_private = inode->i_size; + } + + inode_fake_hash(inode); + +out: + return inode; +} + +/* + * Validate and convert a changed access mode/time to their ADFS equivalents. + * adfs_write_inode will actually write the information back to the directory + * later. + */ +int +adfs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry, + struct iattr *attr) +{ + struct inode *inode = d_inode(dentry); + struct super_block *sb = inode->i_sb; + unsigned int ia_valid = attr->ia_valid; + int error; + + error = setattr_prepare(&nop_mnt_idmap, dentry, attr); + + /* + * we can't change the UID or GID of any file - + * we have a global UID/GID in the superblock + */ + if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, ADFS_SB(sb)->s_uid)) || + (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, ADFS_SB(sb)->s_gid))) + error = -EPERM; + + if (error) + goto out; + + /* XXX: this is missing some actual on-disk truncation.. */ + if (ia_valid & ATTR_SIZE) + truncate_setsize(inode, attr->ia_size); + + if (ia_valid & ATTR_MTIME && adfs_inode_is_stamped(inode)) { + adfs_unix2adfs_time(inode, &attr->ia_mtime); + adfs_adfs2unix_time(&inode->i_mtime, inode); + } + + /* + * FIXME: should we make these == to i_mtime since we don't + * have the ability to represent them in our filesystem? + */ + if (ia_valid & ATTR_ATIME) + inode->i_atime = attr->ia_atime; + if (ia_valid & ATTR_CTIME) + inode_set_ctime_to_ts(inode, attr->ia_ctime); + if (ia_valid & ATTR_MODE) { + ADFS_I(inode)->attr = adfs_mode2atts(sb, inode, attr->ia_mode); + inode->i_mode = adfs_atts2mode(sb, inode); + } + + /* + * FIXME: should we be marking this inode dirty even if + * we don't have any metadata to write back? + */ + if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE)) + mark_inode_dirty(inode); +out: + return error; +} + +/* + * write an existing inode back to the directory, and therefore the disk. + * The adfs-specific inode data has already been updated by + * adfs_notify_change() + */ +int adfs_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + struct super_block *sb = inode->i_sb; + struct object_info obj; + + obj.indaddr = ADFS_I(inode)->indaddr; + obj.name_len = 0; + obj.parent_id = ADFS_I(inode)->parent_id; + obj.loadaddr = ADFS_I(inode)->loadaddr; + obj.execaddr = ADFS_I(inode)->execaddr; + obj.attr = ADFS_I(inode)->attr; + obj.size = inode->i_size; + + return adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL); +} diff --git a/fs/adfs/map.c b/fs/adfs/map.c new file mode 100644 index 0000000000..a81de80c45 --- /dev/null +++ b/fs/adfs/map.c @@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/map.c + * + * Copyright (C) 1997-2002 Russell King + */ +#include <linux/slab.h> +#include <linux/statfs.h> +#include <asm/unaligned.h> +#include "adfs.h" + +/* + * The ADFS map is basically a set of sectors. Each sector is called a + * zone which contains a bitstream made up of variable sized fragments. + * Each bit refers to a set of bytes in the filesystem, defined by + * log2bpmb. This may be larger or smaller than the sector size, but + * the overall size it describes will always be a round number of + * sectors. A fragment id is always idlen bits long. + * + * < idlen > < n > <1> + * +---------+-------//---------+---+ + * | frag id | 0000....000000 | 1 | + * +---------+-------//---------+---+ + * + * The physical disk space used by a fragment is taken from the start of + * the fragment id up to and including the '1' bit - ie, idlen + n + 1 + * bits. + * + * A fragment id can be repeated multiple times in the whole map for + * large or fragmented files. The first map zone a fragment starts in + * is given by fragment id / ids_per_zone - this allows objects to start + * from any zone on the disk. + * + * Free space is described by a linked list of fragments. Each free + * fragment describes free space in the same way as the other fragments, + * however, the frag id specifies an offset (in map bits) from the end + * of this fragment to the start of the next free fragment. + * + * Objects stored on the disk are allocated object ids (we use these as + * our inode numbers.) Object ids contain a fragment id and an optional + * offset. This allows a directory fragment to contain small files + * associated with that directory. + */ + +/* + * For the future... + */ +static DEFINE_RWLOCK(adfs_map_lock); + +/* + * This is fun. We need to load up to 19 bits from the map at an + * arbitrary bit alignment. (We're limited to 19 bits by F+ version 2). + */ +#define GET_FRAG_ID(_map,_start,_idmask) \ + ({ \ + unsigned char *_m = _map + (_start >> 3); \ + u32 _frag = get_unaligned_le32(_m); \ + _frag >>= (_start & 7); \ + _frag & _idmask; \ + }) + +/* + * return the map bit offset of the fragment frag_id in the zone dm. + * Note that the loop is optimised for best asm code - look at the + * output of: + * gcc -D__KERNEL__ -O2 -I../../include -o - -S map.c + */ +static int lookup_zone(const struct adfs_discmap *dm, const unsigned int idlen, + const u32 frag_id, unsigned int *offset) +{ + const unsigned int endbit = dm->dm_endbit; + const u32 idmask = (1 << idlen) - 1; + unsigned char *map = dm->dm_bh->b_data; + unsigned int start = dm->dm_startbit; + unsigned int freelink, fragend; + u32 frag; + + frag = GET_FRAG_ID(map, 8, idmask & 0x7fff); + freelink = frag ? 8 + frag : 0; + + do { + frag = GET_FRAG_ID(map, start, idmask); + + fragend = find_next_bit_le(map, endbit, start + idlen); + if (fragend >= endbit) + goto error; + + if (start == freelink) { + freelink += frag & 0x7fff; + } else if (frag == frag_id) { + unsigned int length = fragend + 1 - start; + + if (*offset < length) + return start + *offset; + *offset -= length; + } + + start = fragend + 1; + } while (start < endbit); + return -1; + +error: + printk(KERN_ERR "adfs: oversized fragment 0x%x at 0x%x-0x%x\n", + frag, start, fragend); + return -1; +} + +/* + * Scan the free space map, for this zone, calculating the total + * number of map bits in each free space fragment. + * + * Note: idmask is limited to 15 bits [3.2] + */ +static unsigned int +scan_free_map(struct adfs_sb_info *asb, struct adfs_discmap *dm) +{ + const unsigned int endbit = dm->dm_endbit; + const unsigned int idlen = asb->s_idlen; + const unsigned int frag_idlen = idlen <= 15 ? idlen : 15; + const u32 idmask = (1 << frag_idlen) - 1; + unsigned char *map = dm->dm_bh->b_data; + unsigned int start = 8, fragend; + u32 frag; + unsigned long total = 0; + + /* + * get fragment id + */ + frag = GET_FRAG_ID(map, start, idmask); + + /* + * If the freelink is null, then no free fragments + * exist in this zone. + */ + if (frag == 0) + return 0; + + do { + start += frag; + + frag = GET_FRAG_ID(map, start, idmask); + + fragend = find_next_bit_le(map, endbit, start + idlen); + if (fragend >= endbit) + goto error; + + total += fragend + 1 - start; + } while (frag >= idlen + 1); + + if (frag != 0) + printk(KERN_ERR "adfs: undersized free fragment\n"); + + return total; +error: + printk(KERN_ERR "adfs: oversized free fragment\n"); + return 0; +} + +static int scan_map(struct adfs_sb_info *asb, unsigned int zone, + const u32 frag_id, unsigned int mapoff) +{ + const unsigned int idlen = asb->s_idlen; + struct adfs_discmap *dm, *dm_end; + int result; + + dm = asb->s_map + zone; + zone = asb->s_map_size; + dm_end = asb->s_map + zone; + + do { + result = lookup_zone(dm, idlen, frag_id, &mapoff); + + if (result != -1) + goto found; + + dm ++; + if (dm == dm_end) + dm = asb->s_map; + } while (--zone > 0); + + return -1; +found: + result -= dm->dm_startbit; + result += dm->dm_startblk; + + return result; +} + +/* + * calculate the amount of free blocks in the map. + * + * n=1 + * total_free = E(free_in_zone_n) + * nzones + */ +void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + struct adfs_discrecord *dr = adfs_map_discrecord(asb->s_map); + struct adfs_discmap *dm; + unsigned int total = 0; + unsigned int zone; + + dm = asb->s_map; + zone = asb->s_map_size; + + do { + total += scan_free_map(asb, dm++); + } while (--zone > 0); + + buf->f_blocks = adfs_disc_size(dr) >> sb->s_blocksize_bits; + buf->f_files = asb->s_ids_per_zone * asb->s_map_size; + buf->f_bavail = + buf->f_bfree = signed_asl(total, asb->s_map2blk); +} + +int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + unsigned int zone, mapoff; + int result; + + /* + * map & root fragment is special - it starts in the center of the + * disk. The other fragments start at zone (frag / ids_per_zone) + */ + if (frag_id == ADFS_ROOT_FRAG) + zone = asb->s_map_size >> 1; + else + zone = frag_id / asb->s_ids_per_zone; + + if (zone >= asb->s_map_size) + goto bad_fragment; + + /* Convert sector offset to map offset */ + mapoff = signed_asl(offset, -asb->s_map2blk); + + read_lock(&adfs_map_lock); + result = scan_map(asb, zone, frag_id, mapoff); + read_unlock(&adfs_map_lock); + + if (result > 0) { + unsigned int secoff; + + /* Calculate sector offset into map block */ + secoff = offset - signed_asl(mapoff, asb->s_map2blk); + return secoff + signed_asl(result, asb->s_map2blk); + } + + adfs_error(sb, "fragment 0x%04x at offset %d not found in map", + frag_id, offset); + return 0; + +bad_fragment: + adfs_error(sb, "invalid fragment 0x%04x (zone = %d, max = %d)", + frag_id, zone, asb->s_map_size); + return 0; +} + +static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map) +{ + unsigned int v0, v1, v2, v3; + int i; + + v0 = v1 = v2 = v3 = 0; + for (i = sb->s_blocksize - 4; i; i -= 4) { + v0 += map[i] + (v3 >> 8); + v3 &= 0xff; + v1 += map[i + 1] + (v0 >> 8); + v0 &= 0xff; + v2 += map[i + 2] + (v1 >> 8); + v1 &= 0xff; + v3 += map[i + 3] + (v2 >> 8); + v2 &= 0xff; + } + v0 += v3 >> 8; + v1 += map[1] + (v0 >> 8); + v2 += map[2] + (v1 >> 8); + v3 += map[3] + (v2 >> 8); + + return v0 ^ v1 ^ v2 ^ v3; +} + +static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm) +{ + unsigned char crosscheck = 0, zonecheck = 1; + int i; + + for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) { + unsigned char *map; + + map = dm[i].dm_bh->b_data; + + if (adfs_calczonecheck(sb, map) != map[0]) { + adfs_error(sb, "zone %d fails zonecheck", i); + zonecheck = 0; + } + crosscheck ^= map[3]; + } + if (crosscheck != 0xff) + adfs_error(sb, "crosscheck != 0xff"); + return crosscheck == 0xff && zonecheck; +} + +/* + * Layout the map - the first zone contains a copy of the disc record, + * and the last zone must be limited to the size of the filesystem. + */ +static void adfs_map_layout(struct adfs_discmap *dm, unsigned int nzones, + struct adfs_discrecord *dr) +{ + unsigned int zone, zone_size; + u64 size; + + zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare); + + dm[0].dm_bh = NULL; + dm[0].dm_startblk = 0; + dm[0].dm_startbit = 32 + ADFS_DR_SIZE_BITS; + dm[0].dm_endbit = 32 + zone_size; + + for (zone = 1; zone < nzones; zone++) { + dm[zone].dm_bh = NULL; + dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS; + dm[zone].dm_startbit = 32; + dm[zone].dm_endbit = 32 + zone_size; + } + + size = adfs_disc_size(dr) >> dr->log2bpmb; + size -= (nzones - 1) * zone_size - ADFS_DR_SIZE_BITS; + dm[nzones - 1].dm_endbit = 32 + size; +} + +static int adfs_map_read(struct adfs_discmap *dm, struct super_block *sb, + unsigned int map_addr, unsigned int nzones) +{ + unsigned int zone; + + for (zone = 0; zone < nzones; zone++) { + dm[zone].dm_bh = sb_bread(sb, map_addr + zone); + if (!dm[zone].dm_bh) + return -EIO; + } + + return 0; +} + +static void adfs_map_relse(struct adfs_discmap *dm, unsigned int nzones) +{ + unsigned int zone; + + for (zone = 0; zone < nzones; zone++) + brelse(dm[zone].dm_bh); +} + +struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + struct adfs_discmap *dm; + unsigned int map_addr, zone_size, nzones; + int ret; + + nzones = dr->nzones | dr->nzones_high << 8; + zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare); + + asb->s_idlen = dr->idlen; + asb->s_map_size = nzones; + asb->s_map2blk = dr->log2bpmb - dr->log2secsize; + asb->s_log2sharesize = dr->log2sharesize; + asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1); + + map_addr = (nzones >> 1) * zone_size - + ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0); + map_addr = signed_asl(map_addr, asb->s_map2blk); + + dm = kmalloc_array(nzones, sizeof(*dm), GFP_KERNEL); + if (dm == NULL) { + adfs_error(sb, "not enough memory"); + return ERR_PTR(-ENOMEM); + } + + adfs_map_layout(dm, nzones, dr); + + ret = adfs_map_read(dm, sb, map_addr, nzones); + if (ret) { + adfs_error(sb, "unable to read map"); + goto error_free; + } + + if (adfs_checkmap(sb, dm)) + return dm; + + adfs_error(sb, "map corrupted"); + +error_free: + adfs_map_relse(dm, nzones); + kfree(dm); + return ERR_PTR(-EIO); +} + +void adfs_free_map(struct super_block *sb) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + + adfs_map_relse(asb->s_map, asb->s_map_size); + kfree(asb->s_map); +} diff --git a/fs/adfs/super.c b/fs/adfs/super.c new file mode 100644 index 0000000000..e8bfc38239 --- /dev/null +++ b/fs/adfs/super.c @@ -0,0 +1,494 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/super.c + * + * Copyright (C) 1997-1999 Russell King + */ +#include <linux/module.h> +#include <linux/init.h> +#include <linux/parser.h> +#include <linux/mount.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/statfs.h> +#include <linux/user_namespace.h> +#include <linux/blkdev.h> +#include "adfs.h" +#include "dir_f.h" +#include "dir_fplus.h" + +#define ADFS_SB_FLAGS SB_NOATIME + +#define ADFS_DEFAULT_OWNER_MASK S_IRWXU +#define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO) + +void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + + printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %pV\n", + sb->s_id, function ? ": " : "", + function ? function : "", &vaf); + + va_end(args); +} + +void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + printk("%sADFS-fs (%s): %pV\n", pfx, sb->s_id, &vaf); + va_end(args); +} + +static int adfs_checkdiscrecord(struct adfs_discrecord *dr) +{ + unsigned int max_idlen; + int i; + + /* sector size must be 256, 512 or 1024 bytes */ + if (dr->log2secsize != 8 && + dr->log2secsize != 9 && + dr->log2secsize != 10) + return 1; + + /* idlen must be at least log2secsize + 3 */ + if (dr->idlen < dr->log2secsize + 3) + return 1; + + /* we cannot have such a large disc that we + * are unable to represent sector offsets in + * 32 bits. This works out at 2.0 TB. + */ + if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize) + return 1; + + /* + * Maximum idlen is limited to 16 bits for new directories by + * the three-byte storage of an indirect disc address. For + * big directories, idlen must be no greater than 19 v2 [1.0] + */ + max_idlen = dr->format_version ? 19 : 16; + if (dr->idlen > max_idlen) + return 1; + + /* reserved bytes should be zero */ + for (i = 0; i < sizeof(dr->unused52); i++) + if (dr->unused52[i] != 0) + return 1; + + return 0; +} + +static void adfs_put_super(struct super_block *sb) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + + adfs_free_map(sb); + kfree_rcu(asb, rcu); +} + +static int adfs_show_options(struct seq_file *seq, struct dentry *root) +{ + struct adfs_sb_info *asb = ADFS_SB(root->d_sb); + + if (!uid_eq(asb->s_uid, GLOBAL_ROOT_UID)) + seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, asb->s_uid)); + if (!gid_eq(asb->s_gid, GLOBAL_ROOT_GID)) + seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, asb->s_gid)); + if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK) + seq_printf(seq, ",ownmask=%o", asb->s_owner_mask); + if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK) + seq_printf(seq, ",othmask=%o", asb->s_other_mask); + if (asb->s_ftsuffix != 0) + seq_printf(seq, ",ftsuffix=%u", asb->s_ftsuffix); + + return 0; +} + +enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_ftsuffix, Opt_err}; + +static const match_table_t tokens = { + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_ownmask, "ownmask=%o"}, + {Opt_othmask, "othmask=%o"}, + {Opt_ftsuffix, "ftsuffix=%u"}, + {Opt_err, NULL} +}; + +static int parse_options(struct super_block *sb, struct adfs_sb_info *asb, + char *options) +{ + char *p; + int option; + + if (!options) + return 0; + + while ((p = strsep(&options, ",")) != NULL) { + substring_t args[MAX_OPT_ARGS]; + int token; + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_uid: + if (match_int(args, &option)) + return -EINVAL; + asb->s_uid = make_kuid(current_user_ns(), option); + if (!uid_valid(asb->s_uid)) + return -EINVAL; + break; + case Opt_gid: + if (match_int(args, &option)) + return -EINVAL; + asb->s_gid = make_kgid(current_user_ns(), option); + if (!gid_valid(asb->s_gid)) + return -EINVAL; + break; + case Opt_ownmask: + if (match_octal(args, &option)) + return -EINVAL; + asb->s_owner_mask = option; + break; + case Opt_othmask: + if (match_octal(args, &option)) + return -EINVAL; + asb->s_other_mask = option; + break; + case Opt_ftsuffix: + if (match_int(args, &option)) + return -EINVAL; + asb->s_ftsuffix = option; + break; + default: + adfs_msg(sb, KERN_ERR, + "unrecognised mount option \"%s\" or missing value", + p); + return -EINVAL; + } + } + return 0; +} + +static int adfs_remount(struct super_block *sb, int *flags, char *data) +{ + struct adfs_sb_info temp_asb; + int ret; + + sync_filesystem(sb); + *flags |= ADFS_SB_FLAGS; + + temp_asb = *ADFS_SB(sb); + ret = parse_options(sb, &temp_asb, data); + if (ret == 0) + *ADFS_SB(sb) = temp_asb; + + return ret; +} + +static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + struct adfs_sb_info *sbi = ADFS_SB(sb); + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + + adfs_map_statfs(sb, buf); + + buf->f_type = ADFS_SUPER_MAGIC; + buf->f_namelen = sbi->s_namelen; + buf->f_bsize = sb->s_blocksize; + buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks; + buf->f_fsid = u64_to_fsid(id); + + return 0; +} + +static struct kmem_cache *adfs_inode_cachep; + +static struct inode *adfs_alloc_inode(struct super_block *sb) +{ + struct adfs_inode_info *ei; + ei = alloc_inode_sb(sb, adfs_inode_cachep, GFP_KERNEL); + if (!ei) + return NULL; + return &ei->vfs_inode; +} + +static void adfs_free_inode(struct inode *inode) +{ + kmem_cache_free(adfs_inode_cachep, ADFS_I(inode)); +} + +static int adfs_drop_inode(struct inode *inode) +{ + /* always drop inodes if we are read-only */ + return !IS_ENABLED(CONFIG_ADFS_FS_RW) || IS_RDONLY(inode); +} + +static void init_once(void *foo) +{ + struct adfs_inode_info *ei = (struct adfs_inode_info *) foo; + + inode_init_once(&ei->vfs_inode); +} + +static int __init init_inodecache(void) +{ + adfs_inode_cachep = kmem_cache_create("adfs_inode_cache", + sizeof(struct adfs_inode_info), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD|SLAB_ACCOUNT), + init_once); + if (adfs_inode_cachep == NULL) + return -ENOMEM; + return 0; +} + +static void destroy_inodecache(void) +{ + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(adfs_inode_cachep); +} + +static const struct super_operations adfs_sops = { + .alloc_inode = adfs_alloc_inode, + .free_inode = adfs_free_inode, + .drop_inode = adfs_drop_inode, + .write_inode = adfs_write_inode, + .put_super = adfs_put_super, + .statfs = adfs_statfs, + .remount_fs = adfs_remount, + .show_options = adfs_show_options, +}; + +static int adfs_probe(struct super_block *sb, unsigned int offset, int silent, + int (*validate)(struct super_block *sb, + struct buffer_head *bh, + struct adfs_discrecord **bhp)) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + struct adfs_discrecord *dr; + struct buffer_head *bh; + unsigned int blocksize = BLOCK_SIZE; + int ret, try; + + for (try = 0; try < 2; try++) { + /* try to set the requested block size */ + if (sb->s_blocksize != blocksize && + !sb_set_blocksize(sb, blocksize)) { + if (!silent) + adfs_msg(sb, KERN_ERR, + "error: unsupported blocksize"); + return -EINVAL; + } + + /* read the buffer */ + bh = sb_bread(sb, offset >> sb->s_blocksize_bits); + if (!bh) { + adfs_msg(sb, KERN_ERR, + "error: unable to read block %u, try %d", + offset >> sb->s_blocksize_bits, try); + return -EIO; + } + + /* validate it */ + ret = validate(sb, bh, &dr); + if (ret) { + brelse(bh); + return ret; + } + + /* does the block size match the filesystem block size? */ + blocksize = 1 << dr->log2secsize; + if (sb->s_blocksize == blocksize) { + asb->s_map = adfs_read_map(sb, dr); + brelse(bh); + return PTR_ERR_OR_ZERO(asb->s_map); + } + + brelse(bh); + } + + return -EIO; +} + +static int adfs_validate_bblk(struct super_block *sb, struct buffer_head *bh, + struct adfs_discrecord **drp) +{ + struct adfs_discrecord *dr; + unsigned char *b_data; + + b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize); + if (adfs_checkbblk(b_data)) + return -EILSEQ; + + /* Do some sanity checks on the ADFS disc record */ + dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); + if (adfs_checkdiscrecord(dr)) + return -EILSEQ; + + *drp = dr; + return 0; +} + +static int adfs_validate_dr0(struct super_block *sb, struct buffer_head *bh, + struct adfs_discrecord **drp) +{ + struct adfs_discrecord *dr; + + /* Do some sanity checks on the ADFS disc record */ + dr = (struct adfs_discrecord *)(bh->b_data + 4); + if (adfs_checkdiscrecord(dr) || dr->nzones_high || dr->nzones != 1) + return -EILSEQ; + + *drp = dr; + return 0; +} + +static int adfs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct adfs_discrecord *dr; + struct object_info root_obj; + struct adfs_sb_info *asb; + struct inode *root; + int ret = -EINVAL; + + sb->s_flags |= ADFS_SB_FLAGS; + + asb = kzalloc(sizeof(*asb), GFP_KERNEL); + if (!asb) + return -ENOMEM; + + sb->s_fs_info = asb; + sb->s_magic = ADFS_SUPER_MAGIC; + sb->s_time_gran = 10000000; + + /* set default options */ + asb->s_uid = GLOBAL_ROOT_UID; + asb->s_gid = GLOBAL_ROOT_GID; + asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK; + asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK; + asb->s_ftsuffix = 0; + + if (parse_options(sb, asb, data)) + goto error; + + /* Try to probe the filesystem boot block */ + ret = adfs_probe(sb, ADFS_DISCRECORD, 1, adfs_validate_bblk); + if (ret == -EILSEQ) + ret = adfs_probe(sb, 0, silent, adfs_validate_dr0); + if (ret == -EILSEQ) { + if (!silent) + adfs_msg(sb, KERN_ERR, + "error: can't find an ADFS filesystem on dev %s.", + sb->s_id); + ret = -EINVAL; + } + if (ret) + goto error; + + /* set up enough so that we can read an inode */ + sb->s_op = &adfs_sops; + + dr = adfs_map_discrecord(asb->s_map); + + root_obj.parent_id = root_obj.indaddr = le32_to_cpu(dr->root); + root_obj.name_len = 0; + /* Set root object date as 01 Jan 1987 00:00:00 */ + root_obj.loadaddr = 0xfff0003f; + root_obj.execaddr = 0xec22c000; + root_obj.size = ADFS_NEWDIR_SIZE; + root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ | + ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ; + + /* + * If this is a F+ disk with variable length directories, + * get the root_size from the disc record. + */ + if (dr->format_version) { + root_obj.size = le32_to_cpu(dr->root_size); + asb->s_dir = &adfs_fplus_dir_ops; + asb->s_namelen = ADFS_FPLUS_NAME_LEN; + } else { + asb->s_dir = &adfs_f_dir_ops; + asb->s_namelen = ADFS_F_NAME_LEN; + } + /* + * ,xyz hex filetype suffix may be added by driver + * to files that have valid RISC OS filetype + */ + if (asb->s_ftsuffix) + asb->s_namelen += 4; + + sb->s_d_op = &adfs_dentry_operations; + root = adfs_iget(sb, &root_obj); + sb->s_root = d_make_root(root); + if (!sb->s_root) { + adfs_free_map(sb); + adfs_error(sb, "get root inode failed\n"); + ret = -EIO; + goto error; + } + return 0; + +error: + sb->s_fs_info = NULL; + kfree(asb); + return ret; +} + +static struct dentry *adfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, adfs_fill_super); +} + +static struct file_system_type adfs_fs_type = { + .owner = THIS_MODULE, + .name = "adfs", + .mount = adfs_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("adfs"); + +static int __init init_adfs_fs(void) +{ + int err = init_inodecache(); + if (err) + goto out1; + err = register_filesystem(&adfs_fs_type); + if (err) + goto out; + return 0; +out: + destroy_inodecache(); +out1: + return err; +} + +static void __exit exit_adfs_fs(void) +{ + unregister_filesystem(&adfs_fs_type); + destroy_inodecache(); +} + +module_init(init_adfs_fs) +module_exit(exit_adfs_fs) +MODULE_LICENSE("GPL"); |