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Diffstat (limited to 'fs/cramfs/inode.c')
-rw-r--r--fs/cramfs/inode.c286
1 files changed, 158 insertions, 128 deletions
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 350680fd7da..ddcfe590b8a 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -17,16 +17,30 @@
#include <linux/init.h>
#include <linux/string.h>
#include <linux/blkdev.h>
-#include <linux/cramfs_fs.h>
#include <linux/slab.h>
-#include <linux/cramfs_fs_sb.h>
-#include <linux/buffer_head.h>
#include <linux/vfs.h>
#include <linux/mutex.h>
-#include <asm/semaphore.h>
-
+#include <uapi/linux/cramfs_fs.h>
#include <asm/uaccess.h>
+#include "internal.h"
+
+/*
+ * cramfs super-block data in memory
+ */
+struct cramfs_sb_info {
+ unsigned long magic;
+ unsigned long size;
+ unsigned long blocks;
+ unsigned long files;
+ unsigned long flags;
+};
+
+static inline struct cramfs_sb_info *CRAMFS_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
static const struct super_operations cramfs_ops;
static const struct inode_operations cramfs_dir_inode_operations;
static const struct file_operations cramfs_directory_operations;
@@ -35,79 +49,81 @@ static const struct address_space_operations cramfs_aops;
static DEFINE_MUTEX(read_mutex);
-/* These two macros may change in future, to provide better st_ino
- semantics. */
-#define CRAMINO(x) (((x)->offset && (x)->size)?(x)->offset<<2:1)
+/* These macros may change in future, to provide better st_ino semantics. */
#define OFFSET(x) ((x)->i_ino)
-
-static int cramfs_iget5_test(struct inode *inode, void *opaque)
+static unsigned long cramino(const struct cramfs_inode *cino, unsigned int offset)
{
- struct cramfs_inode *cramfs_inode = opaque;
-
- if (inode->i_ino != CRAMINO(cramfs_inode))
- return 0; /* does not match */
-
- if (inode->i_ino != 1)
- return 1;
-
- /* all empty directories, char, block, pipe, and sock, share inode #1 */
-
- if ((inode->i_mode != cramfs_inode->mode) ||
- (inode->i_gid != cramfs_inode->gid) ||
- (inode->i_uid != cramfs_inode->uid))
- return 0; /* does not match */
-
- if ((S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) &&
- (inode->i_rdev != old_decode_dev(cramfs_inode->size)))
- return 0; /* does not match */
-
- return 1; /* matches */
+ if (!cino->offset)
+ return offset + 1;
+ if (!cino->size)
+ return offset + 1;
+
+ /*
+ * The file mode test fixes buggy mkcramfs implementations where
+ * cramfs_inode->offset is set to a non zero value for entries
+ * which did not contain data, like devices node and fifos.
+ */
+ switch (cino->mode & S_IFMT) {
+ case S_IFREG:
+ case S_IFDIR:
+ case S_IFLNK:
+ return cino->offset << 2;
+ default:
+ break;
+ }
+ return offset + 1;
}
-static int cramfs_iget5_set(struct inode *inode, void *opaque)
+static struct inode *get_cramfs_inode(struct super_block *sb,
+ const struct cramfs_inode *cramfs_inode, unsigned int offset)
{
+ struct inode *inode;
static struct timespec zerotime;
- struct cramfs_inode *cramfs_inode = opaque;
- inode->i_mode = cramfs_inode->mode;
- inode->i_uid = cramfs_inode->uid;
- inode->i_size = cramfs_inode->size;
- inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
- inode->i_gid = cramfs_inode->gid;
- /* Struct copy intentional */
- inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
- inode->i_ino = CRAMINO(cramfs_inode);
- /* inode->i_nlink is left 1 - arguably wrong for directories,
- but it's the best we can do without reading the directory
- contents. 1 yields the right result in GNU find, even
- without -noleaf option. */
- if (S_ISREG(inode->i_mode)) {
+
+ inode = iget_locked(sb, cramino(cramfs_inode, offset));
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ switch (cramfs_inode->mode & S_IFMT) {
+ case S_IFREG:
inode->i_fop = &generic_ro_fops;
inode->i_data.a_ops = &cramfs_aops;
- } else if (S_ISDIR(inode->i_mode)) {
+ break;
+ case S_IFDIR:
inode->i_op = &cramfs_dir_inode_operations;
inode->i_fop = &cramfs_directory_operations;
- } else if (S_ISLNK(inode->i_mode)) {
+ break;
+ case S_IFLNK:
inode->i_op = &page_symlink_inode_operations;
inode->i_data.a_ops = &cramfs_aops;
- } else {
- inode->i_size = 0;
- inode->i_blocks = 0;
- init_special_inode(inode, inode->i_mode,
- old_decode_dev(cramfs_inode->size));
+ break;
+ default:
+ init_special_inode(inode, cramfs_inode->mode,
+ old_decode_dev(cramfs_inode->size));
}
- return 0;
-}
-static struct inode *get_cramfs_inode(struct super_block *sb,
- struct cramfs_inode * cramfs_inode)
-{
- struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode),
- cramfs_iget5_test, cramfs_iget5_set,
- cramfs_inode);
- if (inode && (inode->i_state & I_NEW)) {
- unlock_new_inode(inode);
+ inode->i_mode = cramfs_inode->mode;
+ i_uid_write(inode, cramfs_inode->uid);
+ i_gid_write(inode, cramfs_inode->gid);
+
+ /* if the lower 2 bits are zero, the inode contains data */
+ if (!(inode->i_ino & 3)) {
+ inode->i_size = cramfs_inode->size;
+ inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
}
+
+ /* Struct copy intentional */
+ inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
+ /* inode->i_nlink is left 1 - arguably wrong for directories,
+ but it's the best we can do without reading the directory
+ contents. 1 yields the right result in GNU find, even
+ without -noleaf option. */
+
+ unlock_new_inode(inode);
+
return inode;
}
@@ -179,8 +195,7 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
struct page *page = NULL;
if (blocknr + i < devsize) {
- page = read_mapping_page_async(mapping, blocknr + i,
- NULL);
+ page = read_mapping_page(mapping, blocknr + i, NULL);
/* synchronous error? */
if (IS_ERR(page))
page = NULL;
@@ -219,14 +234,16 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
return read_buffers[buffer] + offset;
}
-static void cramfs_put_super(struct super_block *sb)
+static void cramfs_kill_sb(struct super_block *sb)
{
- kfree(sb->s_fs_info);
- sb->s_fs_info = NULL;
+ struct cramfs_sb_info *sbi = CRAMFS_SB(sb);
+ kill_block_super(sb);
+ kfree(sbi);
}
static int cramfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
@@ -257,11 +274,11 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
/* Do sanity checks on the superblock */
if (super.magic != CRAMFS_MAGIC) {
- /* check for wrong endianess */
+ /* check for wrong endianness */
if (super.magic == CRAMFS_MAGIC_WEND) {
if (!silent)
- printk(KERN_ERR "cramfs: wrong endianess\n");
- goto out;
+ printk(KERN_ERR "cramfs: wrong endianness\n");
+ return -EINVAL;
}
/* check at 512 byte offset */
@@ -270,24 +287,27 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
mutex_unlock(&read_mutex);
if (super.magic != CRAMFS_MAGIC) {
if (super.magic == CRAMFS_MAGIC_WEND && !silent)
- printk(KERN_ERR "cramfs: wrong endianess\n");
+ printk(KERN_ERR "cramfs: wrong endianness\n");
else if (!silent)
printk(KERN_ERR "cramfs: wrong magic\n");
- goto out;
+ return -EINVAL;
}
}
/* get feature flags first */
if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) {
printk(KERN_ERR "cramfs: unsupported filesystem features\n");
- goto out;
+ return -EINVAL;
}
/* Check that the root inode is in a sane state */
if (!S_ISDIR(super.root.mode)) {
printk(KERN_ERR "cramfs: root is not a directory\n");
- goto out;
+ return -EINVAL;
}
+ /* correct strange, hard-coded permissions of mkcramfs */
+ super.root.mode |= (S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
+
root_offset = super.root.offset << 2;
if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) {
sbi->size=super.size;
@@ -307,29 +327,24 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
(root_offset != 512 + sizeof(struct cramfs_super))))
{
printk(KERN_ERR "cramfs: bad root offset %lu\n", root_offset);
- goto out;
+ return -EINVAL;
}
/* Set it all up.. */
sb->s_op = &cramfs_ops;
- root = get_cramfs_inode(sb, &super.root);
- if (!root)
- goto out;
- sb->s_root = d_alloc_root(root);
- if (!sb->s_root) {
- iput(root);
- goto out;
- }
+ root = get_cramfs_inode(sb, &super.root, 0);
+ if (IS_ERR(root))
+ return PTR_ERR(root);
+ sb->s_root = d_make_root(root);
+ if (!sb->s_root)
+ return -ENOMEM;
return 0;
-out:
- kfree(sbi);
- sb->s_fs_info = NULL;
- return -EINVAL;
}
static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
+ u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
buf->f_type = CRAMFS_MAGIC;
buf->f_bsize = PAGE_CACHE_SIZE;
@@ -338,6 +353,8 @@ static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_bavail = 0;
buf->f_files = CRAMFS_SB(sb)->files;
buf->f_ffree = 0;
+ buf->f_fsid.val[0] = (u32)id;
+ buf->f_fsid.val[1] = (u32)(id >> 32);
buf->f_namelen = CRAMFS_MAXPATHLEN;
return 0;
}
@@ -345,18 +362,17 @@ static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf)
/*
* Read a cramfs directory entry.
*/
-static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+static int cramfs_readdir(struct file *file, struct dir_context *ctx)
{
- struct inode *inode = filp->f_path.dentry->d_inode;
+ struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
char *buf;
unsigned int offset;
- int copied;
/* Offset within the thing. */
- offset = filp->f_pos;
- if (offset >= inode->i_size)
+ if (ctx->pos >= inode->i_size)
return 0;
+ offset = ctx->pos;
/* Directory entries are always 4-byte aligned */
if (offset & 3)
return -EINVAL;
@@ -365,14 +381,13 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
if (!buf)
return -ENOMEM;
- copied = 0;
while (offset < inode->i_size) {
struct cramfs_inode *de;
unsigned long nextoffset;
char *name;
ino_t ino;
- mode_t mode;
- int namelen, error;
+ umode_t mode;
+ int namelen;
mutex_lock(&read_mutex);
de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN);
@@ -385,7 +400,7 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
*/
namelen = de->namelen << 2;
memcpy(buf, name, namelen);
- ino = CRAMINO(de);
+ ino = cramino(de, OFFSET(inode) + offset);
mode = de->mode;
mutex_unlock(&read_mutex);
nextoffset = offset + sizeof(*de) + namelen;
@@ -398,13 +413,10 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
break;
namelen--;
}
- error = filldir(dirent, buf, namelen, offset, ino, mode >> 12);
- if (error)
+ if (!dir_emit(ctx, buf, namelen, ino, mode >> 12))
break;
- offset = nextoffset;
- filp->f_pos = offset;
- copied++;
+ ctx->pos = offset = nextoffset;
}
kfree(buf);
return 0;
@@ -413,9 +425,10 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
/*
* Lookup and fill in the inode data..
*/
-static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
unsigned int offset = 0;
+ struct inode *inode = NULL;
int sorted;
mutex_lock(&read_mutex);
@@ -424,8 +437,9 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
struct cramfs_inode *de;
char *name;
int namelen, retval;
+ int dir_off = OFFSET(dir) + offset;
- de = cramfs_read(dir->i_sb, OFFSET(dir) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN);
+ de = cramfs_read(dir->i_sb, dir_off, sizeof(*de)+CRAMFS_MAXPATHLEN);
name = (char *)(de+1);
/* Try to take advantage of sorted directories */
@@ -441,8 +455,8 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
for (;;) {
if (!namelen) {
- mutex_unlock(&read_mutex);
- return ERR_PTR(-EIO);
+ inode = ERR_PTR(-EIO);
+ goto out;
}
if (name[namelen-1])
break;
@@ -454,28 +468,32 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
if (retval > 0)
continue;
if (!retval) {
- struct cramfs_inode entry = *de;
- mutex_unlock(&read_mutex);
- d_add(dentry, get_cramfs_inode(dir->i_sb, &entry));
- return NULL;
+ inode = get_cramfs_inode(dir->i_sb, de, dir_off);
+ break;
}
/* else (retval < 0) */
if (sorted)
break;
}
+out:
mutex_unlock(&read_mutex);
- d_add(dentry, NULL);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ d_add(dentry, inode);
return NULL;
}
static int cramfs_readpage(struct file *file, struct page * page)
{
struct inode *inode = page->mapping->host;
- u32 maxblock, bytes_filled;
+ u32 maxblock;
+ int bytes_filled;
void *pgdata;
maxblock = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
bytes_filled = 0;
+ pgdata = kmap(page);
+
if (page->index < maxblock) {
struct super_block *sb = inode->i_sb;
u32 blkptr_offset = OFFSET(inode) + page->index*4;
@@ -484,30 +502,43 @@ static int cramfs_readpage(struct file *file, struct page * page)
start_offset = OFFSET(inode) + maxblock*4;
mutex_lock(&read_mutex);
if (page->index)
- start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4, 4);
- compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) - start_offset);
+ start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4,
+ 4);
+ compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) -
+ start_offset);
mutex_unlock(&read_mutex);
- pgdata = kmap(page);
+
if (compr_len == 0)
; /* hole */
- else if (compr_len > (PAGE_CACHE_SIZE << 1))
- printk(KERN_ERR "cramfs: bad compressed blocksize %u\n", compr_len);
- else {
+ else if (unlikely(compr_len > (PAGE_CACHE_SIZE << 1))) {
+ pr_err("cramfs: bad compressed blocksize %u\n",
+ compr_len);
+ goto err;
+ } else {
mutex_lock(&read_mutex);
bytes_filled = cramfs_uncompress_block(pgdata,
PAGE_CACHE_SIZE,
cramfs_read(sb, start_offset, compr_len),
compr_len);
mutex_unlock(&read_mutex);
+ if (unlikely(bytes_filled < 0))
+ goto err;
}
- } else
- pgdata = kmap(page);
+ }
+
memset(pgdata + bytes_filled, 0, PAGE_CACHE_SIZE - bytes_filled);
- kunmap(page);
flush_dcache_page(page);
+ kunmap(page);
SetPageUptodate(page);
unlock_page(page);
return 0;
+
+err:
+ kunmap(page);
+ ClearPageUptodate(page);
+ SetPageError(page);
+ unlock_page(page);
+ return 0;
}
static const struct address_space_operations cramfs_aops = {
@@ -524,7 +555,7 @@ static const struct address_space_operations cramfs_aops = {
static const struct file_operations cramfs_directory_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
- .readdir = cramfs_readdir,
+ .iterate = cramfs_readdir,
};
static const struct inode_operations cramfs_dir_inode_operations = {
@@ -532,25 +563,24 @@ static const struct inode_operations cramfs_dir_inode_operations = {
};
static const struct super_operations cramfs_ops = {
- .put_super = cramfs_put_super,
.remount_fs = cramfs_remount,
.statfs = cramfs_statfs,
};
-static int cramfs_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data, struct vfsmount *mnt)
+static struct dentry *cramfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
{
- return get_sb_bdev(fs_type, flags, dev_name, data, cramfs_fill_super,
- mnt);
+ return mount_bdev(fs_type, flags, dev_name, data, cramfs_fill_super);
}
static struct file_system_type cramfs_fs_type = {
.owner = THIS_MODULE,
.name = "cramfs",
- .get_sb = cramfs_get_sb,
- .kill_sb = kill_block_super,
+ .mount = cramfs_mount,
+ .kill_sb = cramfs_kill_sb,
.fs_flags = FS_REQUIRES_DEV,
};
+MODULE_ALIAS_FS("cramfs");
static int __init init_cramfs_fs(void)
{
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 02:01:13 +0000