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-rw-r--r--fs/adfs/Kconfig28
-rw-r--r--fs/adfs/Makefile8
-rw-r--r--fs/adfs/adfs.h230
-rw-r--r--fs/adfs/dir.c457
-rw-r--r--fs/adfs/dir_f.c324
-rw-r--r--fs/adfs/dir_f.h66
-rw-r--r--fs/adfs/dir_fplus.c287
-rw-r--r--fs/adfs/dir_fplus.h42
-rw-r--r--fs/adfs/file.c36
-rw-r--r--fs/adfs/inode.c369
-rw-r--r--fs/adfs/map.c407
-rw-r--r--fs/adfs/super.c494
12 files changed, 2748 insertions, 0 deletions
diff --git a/fs/adfs/Kconfig b/fs/adfs/Kconfig
new file mode 100644
index 000000000..44738fed6
--- /dev/null
+++ b/fs/adfs/Kconfig
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ADFS_FS
+ tristate "ADFS file system support"
+ depends on BLOCK
+ 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 000000000..cf7de6ece
--- /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 000000000..06b7c9234
--- /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 user_namespace *mnt_userns, 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 000000000..77fbd1960
--- /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 000000000..05e963402
--- /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 000000000..a5393e6cf
--- /dev/null
+++ b/fs/adfs/dir_f.h
@@ -0,0 +1,66 @@
+/* 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));
+
+union adfs_dirtail {
+ struct adfs_olddirtail old;
+ struct adfs_newdirtail new;
+};
+
+#endif
diff --git a/fs/adfs/dir_fplus.c b/fs/adfs/dir_fplus.c
new file mode 100644
index 000000000..4a1592401
--- /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 000000000..d729b1591
--- /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 000000000..754afb14a
--- /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 = generic_file_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 000000000..ee22278b0
--- /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->i_ctime = 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 user_namespace *mnt_userns, 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(&init_user_ns, 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->i_ctime = 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 000000000..a81de80c4
--- /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 000000000..e8bfc3823
--- /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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 12:10:51 +0000