[PATCH] squashfs: thread initialization through the backend framework
From: Ferenc Wagner
Date: Sat Mar 20 2010 - 10:58:21 EST
This necessitated introducing the killsb callback.
The read path is still untouched.
---
fs/squashfs/backend.c | 22 +++++++++++++++-----
fs/squashfs/backend.h | 11 ++++-----
fs/squashfs/bdev.c | 3 +-
fs/squashfs/squashfs.h | 6 ++--
fs/squashfs/super.c | 49 +++++++++++++++++++++--------------------------
5 files changed, 48 insertions(+), 43 deletions(-)
diff --git a/fs/squashfs/backend.c b/fs/squashfs/backend.c
index 4411c60..49fa6fa 100644
--- a/fs/squashfs/backend.c
+++ b/fs/squashfs/backend.c
@@ -11,14 +11,24 @@ const struct squashfs_backend *backends[] = {
NULL
};
-const struct squashfs_backend *
-squashfs_find_backend(struct file_system_type *fs_type, int flags,
+int squashfs_find_backend(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data, struct vfsmount *mnt)
{
const struct squashfs_backend **b;
+ int err;
- for (b = backends; *b; b++)
- if (!(*b)->probe(fs_type, flags, dev_name, data, mnt))
- break;
- return *b;
+ for (b = backends; *b; b++) {
+ err = (*b)->probe(fs_type, flags, dev_name, data, mnt);
+ if (!err)
+ return 0;
+ }
+ ERROR("No suitable backend found\n");
+ return -ENODEV;
+}
+
+void squashfs_kill_super(struct super_block *sb)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+
+ msblk->backend->killsb(sb);
}
diff --git a/fs/squashfs/backend.h b/fs/squashfs/backend.h
index ca3ffe1..02c4bcd 100644
--- a/fs/squashfs/backend.h
+++ b/fs/squashfs/backend.h
@@ -9,14 +9,13 @@ struct squashfs_backend {
ssize_t (*read)(struct squashfs_sb_info *, void **, size_t);
int (*probe)(struct file_system_type *, int, const char *,
void*, struct vfsmount *);
+ void (*killsb)(struct super_block *);
void (*kill)(struct squashfs_sb_info *);
loff_t (*size)(const struct super_block *);
const char *(*devname)(const struct super_block *, char *);
};
-/* Dummy, until the original is nuked */
-static inline int squashfs_fill_super2(struct super_block *sb, void *data,
- int silent, int (*add_bend)(struct super_block *))
-{
- return -1;
-}
+int squashfs_find_backend(struct file_system_type *, int,
+ const char *, void *, struct vfsmount *);
+
+void squashfs_kill_super(struct super_block *);
diff --git a/fs/squashfs/bdev.c b/fs/squashfs/bdev.c
index fcc3b83..81652e8 100644
--- a/fs/squashfs/bdev.c
+++ b/fs/squashfs/bdev.c
@@ -68,7 +68,7 @@ static int add_bdev_backend(struct super_block *sb)
static int fill_bdev_super(struct super_block *sb, void *data, int silent)
{
- return squashfs_fill_super2(sb, data, silent, add_bdev_backend);
+ return squashfs_fill_super(sb, data, silent, add_bdev_backend);
}
static int bdev_probe(struct file_system_type *fs_type, int flags,
@@ -103,6 +103,7 @@ const struct squashfs_backend squashfs_bdev_ops = {
.free = bdev_free,
.read = bdev_read,
.probe = bdev_probe,
+ .killsb = kill_block_super,
.kill = bdev_kill,
.size = bdev_size,
.devname= bdev_devname
diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h
index 0e74175..24c4b9e 100644
--- a/fs/squashfs/squashfs.h
+++ b/fs/squashfs/squashfs.h
@@ -73,10 +73,10 @@ extern struct inode *squashfs_iget(struct super_block *, long long,
unsigned int);
extern int squashfs_read_inode(struct inode *, long long);
-/* super.c
+/* super.c */
int squashfs_fill_super(struct super_block *, void *, int,
- struct squashfs_backend *);
-*/
+ int (*)(struct super_block *));
+
/*
* Inodes, files, backend and decompressor operations
*/
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 3550aec..710179f 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -42,6 +42,7 @@
#include "squashfs_fs_i.h"
#include "squashfs.h"
#include "decompressor.h"
+#include "backend.h"
static struct file_system_type squashfs_fs_type;
static const struct super_operations squashfs_super_ops;
@@ -73,7 +74,8 @@ static const struct squashfs_decompressor *supported_squashfs_filesystem(short
}
-static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
+int squashfs_fill_super(struct super_block *sb, void *data, int silent,
+ int (*add_backend)(struct super_block *))
{
struct squashfs_sb_info *msblk;
struct squashfs_super_block *sblk = NULL;
@@ -97,11 +99,15 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
if (sblk == NULL) {
ERROR("Failed to allocate squashfs_super_block\n");
- goto failure;
+ err = -ENOMEM;
+ goto free_msblk;
}
msblk->devblksize = sb_min_blocksize(sb, BLOCK_SIZE);
msblk->devblksize_log2 = ffz(~msblk->devblksize);
+ err = add_backend(sb);
+ if (err)
+ goto free_sblk;
mutex_init(&msblk->read_data_mutex);
mutex_init(&msblk->meta_index_mutex);
@@ -127,7 +133,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
if (sb->s_magic != SQUASHFS_MAGIC) {
if (!silent)
ERROR("Can't find a SQUASHFS superblock on %s\n",
- bdevname(sb->s_bdev, b));
+ msblk->backend->devname(sb, b));
goto failed_mount;
}
@@ -146,11 +152,10 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
if (le64_to_cpu(sblk->xattr_table_start) != SQUASHFS_INVALID_BLK)
ERROR("Xattrs in filesystem, these will be ignored\n");
- /* Check the filesystem does not extend beyond the end of the
- block device */
+ /* Check the filesystem does not extend beyond the end of the device */
msblk->bytes_used = le64_to_cpu(sblk->bytes_used);
if (msblk->bytes_used < 0 || msblk->bytes_used >
- i_size_read(sb->s_bdev->bd_inode))
+ msblk->backend->size(sb))
goto failed_mount;
/* Check block size for sanity */
@@ -182,7 +187,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
msblk->inodes = le32_to_cpu(sblk->inodes);
flags = le16_to_cpu(sblk->flags);
- TRACE("Found valid superblock on %s\n", bdevname(sb->s_bdev, b));
+ TRACE("Found valid superblock on %s\n", msblk->backend->devname(sb, b));
TRACE("Inodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(flags)
? "un" : "");
TRACE("Data is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(flags)
@@ -297,18 +302,16 @@ failed_mount:
squashfs_cache_delete(msblk->fragment_cache);
squashfs_cache_delete(msblk->read_page);
squashfs_decompressor_free(msblk, msblk->stream);
- kfree(msblk->inode_lookup_table);
+ kfree(msblk->inode_lookup_table); /* FIXME: squashfs_put_super has meta_index instead */
kfree(msblk->fragment_index);
kfree(msblk->id_table);
- kfree(sb->s_fs_info);
- sb->s_fs_info = NULL;
+ msblk->backend->kill(msblk);
+free_sblk:
kfree(sblk);
- return err;
-
-failure:
- kfree(sb->s_fs_info);
+free_msblk:
+ kfree(msblk);
sb->s_fs_info = NULL;
- return -ENOMEM;
+ return err;
}
@@ -353,7 +356,8 @@ static void squashfs_put_super(struct super_block *sb)
kfree(sbi->id_table);
kfree(sbi->fragment_index);
kfree(sbi->meta_index);
- kfree(sb->s_fs_info);
+ sbi->backend->kill(sbi);
+ kfree(sbi);
sb->s_fs_info = NULL;
}
@@ -361,15 +365,6 @@ static void squashfs_put_super(struct super_block *sb)
}
-static int squashfs_get_sb(struct file_system_type *fs_type, int flags,
- const char *dev_name, void *data,
- struct vfsmount *mnt)
-{
- return get_sb_bdev(fs_type, flags, dev_name, data, squashfs_fill_super,
- mnt);
-}
-
-
static struct kmem_cache *squashfs_inode_cachep;
@@ -442,8 +437,8 @@ static void squashfs_destroy_inode(struct inode *inode)
static struct file_system_type squashfs_fs_type = {
.owner = THIS_MODULE,
.name = "squashfs",
- .get_sb = squashfs_get_sb,
- .kill_sb = kill_block_super,
+ .get_sb = squashfs_find_backend,
+ .kill_sb = squashfs_kill_super,
.fs_flags = FS_REQUIRES_DEV
};
--
1.5.6.5