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Subject[RESEND][PATCH 7/9] Ext3: extended attribute sharing fixes and in-inode EAs
Cleanup and prepare ext3 for in-inode xattrs

Clean up several things in the xattr code, and prepare it for
in-inode attributes:

* Add the ext3_xattr_check_names, ext3_xattr_check_block, and
ext3_xattr_check_entry functions for checking xattr data
structures.
* Add the ext3_xattr_find_entry, ext3_xattr_list_entries, and
ext3_xattr_set_entry functions for manipulating xattr entries.
Switch to using these functions in ext3_xattr_get,
ext3_xattr_list, and ext3_xattr_set_handle.
* Merge ext3_xattr_set_handle and ext3_xattr_set_handle2.
* Rename the HDR and FIRST_ENTRY macros.
* We have no way to deal with a ext3_xattr_cache_insert failure,
so make it return void.
* Make the debug messages more useful.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>

Index: linux-2.6.10/fs/ext2/xattr.c
===================================================================
--- linux-2.6.10.orig/fs/ext2/xattr.c
+++ linux-2.6.10/fs/ext2/xattr.c
@@ -24,7 +24,7 @@
*
* +------------------+
* | header |
- * ¦ entry 1 | |
+ * | entry 1 | |
* | entry 2 | | growing downwards
* | entry 3 | v
* | four null bytes |
Index: linux-2.6.10/fs/ext3/xattr.c
===================================================================
--- linux-2.6.10.orig/fs/ext3/xattr.c
+++ linux-2.6.10/fs/ext3/xattr.c
@@ -24,7 +24,7 @@
*
* +------------------+
* | header |
- * ¦ entry 1 | |
+ * | entry 1 | |
* | entry 2 | | growing downwards
* | entry 3 | v
* | four null bytes |
@@ -64,9 +64,9 @@
#include "xattr.h"
#include "acl.h"

-#define HDR(bh) ((struct ext3_xattr_header *)((bh)->b_data))
+#define BHDR(bh) ((struct ext3_xattr_header *)((bh)->b_data))
#define ENTRY(ptr) ((struct ext3_xattr_entry *)(ptr))
-#define FIRST_ENTRY(bh) ENTRY(HDR(bh)+1)
+#define BFIRST(bh) ENTRY(BHDR(bh)+1)
#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)

#ifdef EXT3_XATTR_DEBUG
@@ -89,11 +89,7 @@
# define ea_bdebug(f...)
#endif

-static int ext3_xattr_set_handle2(handle_t *, struct inode *,
- struct buffer_head *,
- struct ext3_xattr_header *);
-
-static int ext3_xattr_cache_insert(struct buffer_head *);
+static void ext3_xattr_cache_insert(struct buffer_head *);
static struct buffer_head *ext3_xattr_cache_find(struct inode *,
struct ext3_xattr_header *,
struct mb_cache_entry **);
@@ -148,6 +144,68 @@ ext3_listxattr(struct dentry *dentry, ch
return ext3_xattr_list(dentry->d_inode, buffer, size);
}

+static int
+ext3_xattr_check_names(struct ext3_xattr_entry *entry, void *end)
+{
+ while (!IS_LAST_ENTRY(entry)) {
+ struct ext3_xattr_entry *next = EXT3_XATTR_NEXT(entry);
+ if ((void *)next >= end)
+ return -EIO;
+ entry = next;
+ }
+ return 0;
+}
+
+static inline int
+ext3_xattr_check_block(struct buffer_head *bh)
+{
+ int error;
+
+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
+ BHDR(bh)->h_blocks != cpu_to_le32(1))
+ return -EIO;
+ error = ext3_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size);
+ return error;
+}
+
+static inline int
+ext3_xattr_check_entry(struct ext3_xattr_entry *entry, size_t size)
+{
+ size_t value_size = le32_to_cpu(entry->e_value_size);
+
+ if (entry->e_value_block != 0 || value_size > size ||
+ le16_to_cpu(entry->e_value_offs) + value_size > size)
+ return -EIO;
+ return 0;
+}
+
+static int
+ext3_xattr_find_entry(struct ext3_xattr_entry **pentry, int name_index,
+ const char *name, size_t size, int sorted)
+{
+ struct ext3_xattr_entry *entry;
+ size_t name_len;
+ int cmp = 1;
+
+ if (name == NULL)
+ return -EINVAL;
+ name_len = strlen(name);
+ entry = *pentry;
+ for (; !IS_LAST_ENTRY(entry); entry = EXT3_XATTR_NEXT(entry)) {
+ cmp = name_index - entry->e_name_index;
+ if (!cmp)
+ cmp = name_len - entry->e_name_len;
+ if (!cmp)
+ cmp = memcmp(name, entry->e_name, name_len);
+ if (cmp <= 0 && (sorted || cmp == 0))
+ break;
+ }
+ *pentry = entry;
+ if (!cmp && ext3_xattr_check_entry(entry, size))
+ return -EIO;
+ return cmp ? -ENODATA : 0;
+}
+
/*
* ext3_xattr_get()
*
@@ -164,8 +222,7 @@ ext3_xattr_get(struct inode *inode, int
{
struct buffer_head *bh = NULL;
struct ext3_xattr_entry *entry;
- size_t name_len, size;
- char *end;
+ size_t size;
int error;

ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
@@ -179,78 +236,65 @@ ext3_xattr_get(struct inode *inode, int
goto cleanup;
ea_idebug(inode, "reading block %d", EXT3_I(inode)->i_file_acl);
bh = sb_bread(inode->i_sb, EXT3_I(inode)->i_file_acl);
- error = -EIO;
if (!bh)
goto cleanup;
ea_bdebug(bh, "b_count=%d, refcount=%d",
- atomic_read(&(bh->b_count)), le32_to_cpu(HDR(bh)->h_refcount));
- end = bh->b_data + bh->b_size;
- if (HDR(bh)->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
- HDR(bh)->h_blocks != cpu_to_le32(1)) {
-bad_block: ext3_error(inode->i_sb, "ext3_xattr_get",
- "inode %ld: bad block %d", inode->i_ino,
- EXT3_I(inode)->i_file_acl);
+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
+ if (ext3_xattr_check_block(bh)) {
+bad_block: ext3_error(inode->i_sb, __FUNCTION__,
+ "inode %ld: bad block %d", inode->i_ino,
+ EXT3_I(inode)->i_file_acl);
error = -EIO;
goto cleanup;
}
- /* find named attribute */
- name_len = strlen(name);
-
- error = -ERANGE;
- if (name_len > 255)
- goto cleanup;
- entry = FIRST_ENTRY(bh);
- while (!IS_LAST_ENTRY(entry)) {
- struct ext3_xattr_entry *next =
- EXT3_XATTR_NEXT(entry);
- if ((char *)next >= end)
- goto bad_block;
- if (name_index == entry->e_name_index &&
- name_len == entry->e_name_len &&
- memcmp(name, entry->e_name, name_len) == 0)
- goto found;
- entry = next;
- }
- /* Check the remaining name entries */
- while (!IS_LAST_ENTRY(entry)) {
- struct ext3_xattr_entry *next =
- EXT3_XATTR_NEXT(entry);
- if ((char *)next >= end)
- goto bad_block;
- entry = next;
- }
- if (ext3_xattr_cache_insert(bh))
- ea_idebug(inode, "cache insert failed");
- error = -ENODATA;
- goto cleanup;
-found:
- /* check the buffer size */
- if (entry->e_value_block != 0)
+ ext3_xattr_cache_insert(bh);
+ entry = BFIRST(bh);
+ error = ext3_xattr_find_entry(&entry, name_index, name, bh->b_size, 1);
+ if (error == -EIO)
goto bad_block;
+ if (error)
+ goto cleanup;
size = le32_to_cpu(entry->e_value_size);
- if (size > inode->i_sb->s_blocksize ||
- le16_to_cpu(entry->e_value_offs) + size > inode->i_sb->s_blocksize)
- goto bad_block;
-
- if (ext3_xattr_cache_insert(bh))
- ea_idebug(inode, "cache insert failed");
if (buffer) {
error = -ERANGE;
if (size > buffer_size)
goto cleanup;
- /* return value of attribute */
memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
- size);
+ size);
}
error = size;

cleanup:
brelse(bh);
up_read(&EXT3_I(inode)->xattr_sem);
-
return error;
}

+static int
+ext3_xattr_list_entries(struct inode *inode, struct ext3_xattr_entry *entry,
+ char *buffer, size_t buffer_size)
+{
+ size_t rest = buffer_size;
+
+ for (; !IS_LAST_ENTRY(entry); entry = EXT3_XATTR_NEXT(entry)) {
+ struct xattr_handler *handler =
+ ext3_xattr_handler(entry->e_name_index);
+
+ if (handler) {
+ size_t size = handler->list(inode, buffer, rest,
+ entry->e_name,
+ entry->e_name_len);
+ if (buffer) {
+ if (size > rest)
+ return -ERANGE;
+ buffer += size;
+ }
+ rest -= size;
+ }
+ }
+ return buffer_size - rest;
+}
+
/*
* ext3_xattr_list()
*
@@ -265,9 +309,6 @@ int
ext3_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
{
struct buffer_head *bh = NULL;
- struct ext3_xattr_entry *entry;
- char *end;
- size_t rest = buffer_size;
int error;

ea_idebug(inode, "buffer=%p, buffer_size=%ld",
@@ -283,50 +324,16 @@ ext3_xattr_list(struct inode *inode, cha
if (!bh)
goto cleanup;
ea_bdebug(bh, "b_count=%d, refcount=%d",
- atomic_read(&(bh->b_count)), le32_to_cpu(HDR(bh)->h_refcount));
- end = bh->b_data + bh->b_size;
- if (HDR(bh)->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
- HDR(bh)->h_blocks != cpu_to_le32(1)) {
-bad_block: ext3_error(inode->i_sb, "ext3_xattr_list",
- "inode %ld: bad block %d", inode->i_ino,
- EXT3_I(inode)->i_file_acl);
+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
+ if (ext3_xattr_check_block(bh)) {
+ ext3_error(inode->i_sb, __FUNCTION__,
+ "inode %ld: bad block %d", inode->i_ino,
+ EXT3_I(inode)->i_file_acl);
error = -EIO;
goto cleanup;
}
-
- /* check the on-disk data structure */
- entry = FIRST_ENTRY(bh);
- while (!IS_LAST_ENTRY(entry)) {
- struct ext3_xattr_entry *next = EXT3_XATTR_NEXT(entry);
-
- if ((char *)next >= end)
- goto bad_block;
- entry = next;
- }
- if (ext3_xattr_cache_insert(bh))
- ea_idebug(inode, "cache insert failed");
-
- /* list the attribute names */
- for (entry = FIRST_ENTRY(bh); !IS_LAST_ENTRY(entry);
- entry = EXT3_XATTR_NEXT(entry)) {
- struct xattr_handler *handler =
- ext3_xattr_handler(entry->e_name_index);
-
- if (handler) {
- size_t size = handler->list(inode, buffer, rest,
- entry->e_name,
- entry->e_name_len);
- if (buffer) {
- if (size > rest) {
- error = -ERANGE;
- goto cleanup;
- }
- buffer += size;
- }
- rest -= size;
- }
- }
- error = buffer_size - rest; /* total size */
+ ext3_xattr_cache_insert(bh);
+ error = ext3_xattr_list_entries(inode, BFIRST(bh), buffer, buffer_size);

cleanup:
brelse(bh);
@@ -366,8 +373,8 @@ ext3_xattr_release_block(handle_t *handl
struct mb_cache_entry *ce = NULL;

ce = mb_cache_entry_get(ext3_xattr_cache, bh->b_bdev, bh->b_blocknr);
- if (HDR(bh)->h_refcount == cpu_to_le32(1)) {
- ea_bdebug(bh, "freeing");
+ if (BHDR(bh)->h_refcount == cpu_to_le32(1)) {
+ ea_bdebug(bh, "refcount now=0; freeing");
if (ce)
mb_cache_entry_free(ce);
ext3_free_blocks(handle, inode, bh->b_blocknr, 1);
@@ -376,20 +383,137 @@ ext3_xattr_release_block(handle_t *handl
} else {
if (ext3_journal_get_write_access(handle, bh) == 0) {
lock_buffer(bh);
- HDR(bh)->h_refcount = cpu_to_le32(
- le32_to_cpu(HDR(bh)->h_refcount) - 1);
+ BHDR(bh)->h_refcount = cpu_to_le32(
+ le32_to_cpu(BHDR(bh)->h_refcount) - 1);
ext3_journal_dirty_metadata(handle, bh);
if (IS_SYNC(inode))
handle->h_sync = 1;
DQUOT_FREE_BLOCK(inode, 1);
unlock_buffer(bh);
- ea_bdebug(bh, "refcount now=%d",
- le32_to_cpu(HDR(bh)->h_refcount) - 1);
+ ea_bdebug(bh, "refcount now=%d; releasing",
+ le32_to_cpu(BHDR(bh)->h_refcount));
}
if (ce)
mb_cache_entry_release(ce);
}
}
+
+struct ext3_xattr_info {
+ int name_index;
+ const char *name;
+ const void *value;
+ size_t value_len;
+};
+
+struct ext3_xattr_search {
+ struct ext3_xattr_entry *first;
+ void *base;
+ void *end;
+ struct ext3_xattr_entry *here;
+ int not_found;
+};
+
+static int
+ext3_xattr_set_entry(struct ext3_xattr_info *i, struct ext3_xattr_search *s)
+{
+ struct ext3_xattr_entry *last;
+ size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
+
+ /* Compute min_offs and last. */
+ last = s->first;
+ for (; !IS_LAST_ENTRY(last); last = EXT3_XATTR_NEXT(last)) {
+ if (!last->e_value_block && last->e_value_size) {
+ size_t offs = le16_to_cpu(last->e_value_offs);
+ if (offs < min_offs)
+ min_offs = offs;
+ }
+ }
+ free = min_offs - ((void *)last - s->base) - sizeof(__u32);
+ if (!s->not_found) {
+ if (!s->here->e_value_block && s->here->e_value_size) {
+ size_t size = le32_to_cpu(s->here->e_value_size);
+ free += EXT3_XATTR_SIZE(size);
+ }
+ free += EXT3_XATTR_LEN(name_len);
+ }
+ if (i->value) {
+ if (free < EXT3_XATTR_SIZE(i->value_len) ||
+ free < EXT3_XATTR_LEN(name_len) +
+ EXT3_XATTR_SIZE(i->value_len))
+ return -ENOSPC;
+ }
+
+ if (i->value && s->not_found) {
+ /* Insert the new name. */
+ size_t size = EXT3_XATTR_LEN(name_len);
+ size_t rest = (void *)last - (void *)s->here + sizeof(__u32);
+ memmove((void *)s->here + size, s->here, rest);
+ memset(s->here, 0, size);
+ s->here->e_name_index = i->name_index;
+ s->here->e_name_len = name_len;
+ memcpy(s->here->e_name, i->name, name_len);
+ } else {
+ if (!s->here->e_value_block && s->here->e_value_size) {
+ void *first_val = s->base + min_offs;
+ size_t offs = le16_to_cpu(s->here->e_value_offs);
+ void *val = s->base + offs;
+ size_t size = EXT3_XATTR_SIZE(
+ le32_to_cpu(s->here->e_value_size));
+
+ if (i->value && size == EXT3_XATTR_SIZE(i->value_len)) {
+ /* The old and the new value have the same
+ size. Just replace. */
+ s->here->e_value_size =
+ cpu_to_le32(i->value_len);
+ memset(val + size - EXT3_XATTR_PAD, 0,
+ EXT3_XATTR_PAD); /* Clear pad bytes. */
+ memcpy(val, i->value, i->value_len);
+ return 0;
+ }
+
+ /* Remove the old value. */
+ memmove(first_val + size, first_val, val - first_val);
+ memset(first_val, 0, size);
+ s->here->e_value_size = 0;
+ s->here->e_value_offs = 0;
+ min_offs += size;
+
+ /* Adjust all value offsets. */
+ last = s->first;
+ while (!IS_LAST_ENTRY(last)) {
+ size_t o = le16_to_cpu(last->e_value_offs);
+ if (!last->e_value_block &&
+ last->e_value_size && o < offs)
+ last->e_value_offs =
+ cpu_to_le16(o + size);
+ last = EXT3_XATTR_NEXT(last);
+ }
+ }
+ if (!i->value) {
+ /* Remove the old name. */
+ size_t size = EXT3_XATTR_LEN(name_len);
+ last = ENTRY((void *)last - size);
+ memmove(s->here, (void *)s->here + size,
+ (void *)last - (void *)s->here + sizeof(__u32));
+ memset(last, 0, size);
+ }
+ }
+
+ if (i->value) {
+ /* Insert the new value. */
+ s->here->e_value_size = cpu_to_le32(i->value_len);
+ if (i->value_len) {
+ size_t size = EXT3_XATTR_SIZE(i->value_len);
+ void *val = s->base + min_offs - size;
+ s->here->e_value_offs = cpu_to_le16(min_offs - size);
+ memset(val + size - EXT3_XATTR_PAD, 0,
+ EXT3_XATTR_PAD); /* Clear the pad bytes. */
+ memcpy(val, i->value, i->value_len);
+ }
+ }
+ return 0;
+}
+
/*
* ext3_xattr_set_handle()
*
@@ -408,23 +532,24 @@ ext3_xattr_set_handle(handle_t *handle,
int flags)
{
struct super_block *sb = inode->i_sb;
- struct buffer_head *bh = NULL;
- struct ext3_xattr_header *header = NULL;
- struct ext3_xattr_entry *here, *last;
- size_t name_len, free, min_offs = sb->s_blocksize;
- int not_found = 1, error;
- char *end;
+ struct buffer_head *old_bh = NULL, *new_bh = NULL;
+ struct ext3_xattr_info i = {
+ .name_index = name_index,
+ .name = name,
+ .value = value,
+ .value_len = value_len,
+ };
+ struct ext3_xattr_search s = {
+ .not_found = 1,
+ };
+ struct mb_cache_entry *ce = NULL;
+ int error;
+
+#define header ((struct ext3_xattr_header *)(s.base))

/*
* header -- Points either into bh, or to a temporarily
* allocated buffer.
- * here -- The named entry found, or the place for inserting, within
- * the block pointed to by header.
- * last -- Points right after the last named entry within the block
- * pointed to by header.
- * min_offs -- The offset of the first value (values are aligned
- * towards the end of the block).
- * end -- Points right after the block pointed to by header.
*/

ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
@@ -434,77 +559,38 @@ ext3_xattr_set_handle(handle_t *handle,
return -EROFS;
if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
return -EPERM;
- if (value == NULL)
- value_len = 0;
- if (name == NULL)
- return -EINVAL;
- name_len = strlen(name);
- if (name_len > 255 || value_len > sb->s_blocksize)
- return -ERANGE;
+ if (i.value == NULL)
+ i.value_len = 0;
down_write(&EXT3_I(inode)->xattr_sem);
if (EXT3_I(inode)->i_file_acl) {
/* The inode already has an extended attribute block. */
- bh = sb_bread(sb, EXT3_I(inode)->i_file_acl);
+ old_bh = sb_bread(sb, EXT3_I(inode)->i_file_acl);
error = -EIO;
- if (!bh)
+ if (!old_bh)
goto cleanup;
- ea_bdebug(bh, "b_count=%d, refcount=%d",
- atomic_read(&(bh->b_count)),
- le32_to_cpu(HDR(bh)->h_refcount));
- header = HDR(bh);
- end = bh->b_data + bh->b_size;
- if (header->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
- header->h_blocks != cpu_to_le32(1)) {
-bad_block: ext3_error(sb, "ext3_xattr_set",
+ ea_bdebug(old_bh, "b_count=%d, refcount=%d",
+ atomic_read(&(old_bh->b_count)),
+ le32_to_cpu(BHDR(old_bh)->h_refcount));
+ if (ext3_xattr_check_block(old_bh)) {
+bad_block: ext3_error(sb, __FUNCTION__,
"inode %ld: bad block %d", inode->i_ino,
EXT3_I(inode)->i_file_acl);
error = -EIO;
goto cleanup;
}
/* Find the named attribute. */
- here = FIRST_ENTRY(bh);
- while (!IS_LAST_ENTRY(here)) {
- struct ext3_xattr_entry *next = EXT3_XATTR_NEXT(here);
- if ((char *)next >= end)
- goto bad_block;
- if (!here->e_value_block && here->e_value_size) {
- size_t offs = le16_to_cpu(here->e_value_offs);
- if (offs < min_offs)
- min_offs = offs;
- }
- not_found = name_index - here->e_name_index;
- if (!not_found)
- not_found = name_len - here->e_name_len;
- if (!not_found)
- not_found = memcmp(name, here->e_name,name_len);
- if (not_found <= 0)
- break;
- here = next;
- }
- last = here;
- /* We still need to compute min_offs and last. */
- while (!IS_LAST_ENTRY(last)) {
- struct ext3_xattr_entry *next = EXT3_XATTR_NEXT(last);
- if ((char *)next >= end)
- goto bad_block;
- if (!last->e_value_block && last->e_value_size) {
- size_t offs = le16_to_cpu(last->e_value_offs);
- if (offs < min_offs)
- min_offs = offs;
- }
- last = next;
- }
-
- /* Check whether we have enough space left. */
- free = min_offs - ((char*)last - (char*)header) - sizeof(__u32);
- } else {
- /* We will use a new extended attribute block. */
- free = sb->s_blocksize -
- sizeof(struct ext3_xattr_header) - sizeof(__u32);
- here = last = NULL; /* avoid gcc uninitialized warning. */
+ s.base = BHDR(old_bh);
+ s.first = BFIRST(old_bh);
+ s.end = old_bh->b_data + old_bh->b_size;
+ s.here = BFIRST(old_bh);
+ error = ext3_xattr_find_entry(&s.here, name_index, name,
+ old_bh->b_size, 1);
+ if (error && error != -ENODATA)
+ goto cleanup;
+ s.not_found = error;
}

- if (not_found) {
+ if (s.not_found) {
/* Request to remove a nonexistent attribute? */
error = -ENODATA;
if (flags & XATTR_REPLACE)
@@ -517,183 +603,90 @@ bad_block: ext3_error(sb, "ext3_xattr_s
error = -EEXIST;
if (flags & XATTR_CREATE)
goto cleanup;
- if (!here->e_value_block && here->e_value_size) {
- size_t size = le32_to_cpu(here->e_value_size);
-
- if (le16_to_cpu(here->e_value_offs) + size >
- sb->s_blocksize || size > sb->s_blocksize)
- goto bad_block;
- free += EXT3_XATTR_SIZE(size);
- }
- free += EXT3_XATTR_LEN(name_len);
}
- error = -ENOSPC;
- if (free < EXT3_XATTR_LEN(name_len) + EXT3_XATTR_SIZE(value_len))
- goto cleanup;
-
- /* Here we know that we can set the new attribute. */

if (header) {
- struct mb_cache_entry *ce;
-
- /* assert(header == HDR(bh)); */
- ce = mb_cache_entry_get(ext3_xattr_cache, bh->b_bdev,
- bh->b_blocknr);
+ /* assert(header == BHDR(old_bh)); */
+ ce = mb_cache_entry_get(ext3_xattr_cache, old_bh->b_bdev,
+ old_bh->b_blocknr);
if (header->h_refcount == cpu_to_le32(1)) {
- if (ce)
+ if (ce) {
mb_cache_entry_free(ce);
- ea_bdebug(bh, "modifying in-place");
- error = ext3_journal_get_write_access(handle, bh);
+ ce = NULL;
+ }
+ ea_bdebug(old_bh, "modifying in-place");
+ error = ext3_journal_get_write_access(handle, old_bh);
if (error)
goto cleanup;
- lock_buffer(bh);
- /* keep the buffer locked while modifying it. */
+ lock_buffer(old_bh);
+ error = ext3_xattr_set_entry(&i, &s);
+ if (!error) {
+ if (!IS_LAST_ENTRY(s.first))
+ ext3_xattr_rehash(header, s.here);
+ ext3_xattr_cache_insert(old_bh);
+ }
+ unlock_buffer(old_bh);
+ if (error == -EIO)
+ goto bad_block;
+ if (!error && old_bh && header == BHDR(old_bh)) {
+ error = ext3_journal_dirty_metadata(handle,
+ old_bh);
+ }
+ if (error)
+ goto cleanup;
+ goto inserted;
} else {
- int offset;
+ int offset = (char *)s.here - old_bh->b_data;

- if (ce)
+ if (ce) {
mb_cache_entry_release(ce);
- ea_bdebug(bh, "cloning");
- header = kmalloc(bh->b_size, GFP_KERNEL);
+ ce = NULL;
+ }
+ ea_bdebug(old_bh, "cloning");
+ s.base = kmalloc(old_bh->b_size, GFP_KERNEL);
+ /*assert(header == s.base)*/
error = -ENOMEM;
if (header == NULL)
goto cleanup;
- memcpy(header, HDR(bh), bh->b_size);
+ memcpy(header, BHDR(old_bh), old_bh->b_size);
+ s.first = ENTRY(header+1);
header->h_refcount = cpu_to_le32(1);
- offset = (char *)here - bh->b_data;
- here = ENTRY((char *)header + offset);
- offset = (char *)last - bh->b_data;
- last = ENTRY((char *)header + offset);
+ s.here = ENTRY(s.base + offset);
+ s.end = header + old_bh->b_size;
}
} else {
/* Allocate a buffer where we construct the new block. */
- header = kmalloc(sb->s_blocksize, GFP_KERNEL);
+ s.base = kmalloc(sb->s_blocksize, GFP_KERNEL);
+ /*assert(header == s.base)*/
error = -ENOMEM;
if (header == NULL)
goto cleanup;
memset(header, 0, sb->s_blocksize);
- end = (char *)header + sb->s_blocksize;
header->h_magic = cpu_to_le32(EXT3_XATTR_MAGIC);
header->h_blocks = header->h_refcount = cpu_to_le32(1);
- last = here = ENTRY(header+1);
+ s.first = ENTRY(header+1);
+ s.here = ENTRY(header+1);
+ s.end = (void *)header + sb->s_blocksize;
}

- /* Iff we are modifying the block in-place, bh is locked here. */
-
- if (not_found) {
- /* Insert the new name. */
- size_t size = EXT3_XATTR_LEN(name_len);
- size_t rest = (char *)last - (char *)here;
- memmove((char *)here + size, here, rest);
- memset(here, 0, size);
- here->e_name_index = name_index;
- here->e_name_len = name_len;
- memcpy(here->e_name, name, name_len);
- } else {
- if (!here->e_value_block && here->e_value_size) {
- char *first_val = (char *)header + min_offs;
- size_t offs = le16_to_cpu(here->e_value_offs);
- char *val = (char *)header + offs;
- size_t size = EXT3_XATTR_SIZE(
- le32_to_cpu(here->e_value_size));
-
- if (size == EXT3_XATTR_SIZE(value_len)) {
- /* The old and the new value have the same
- size. Just replace. */
- here->e_value_size = cpu_to_le32(value_len);
- memset(val + size - EXT3_XATTR_PAD, 0,
- EXT3_XATTR_PAD); /* Clear pad bytes. */
- memcpy(val, value, value_len);
- goto skip_replace;
- }
-
- /* Remove the old value. */
- memmove(first_val + size, first_val, val - first_val);
- memset(first_val, 0, size);
- here->e_value_offs = 0;
- min_offs += size;
-
- /* Adjust all value offsets. */
- last = ENTRY(header+1);
- while (!IS_LAST_ENTRY(last)) {
- size_t o = le16_to_cpu(last->e_value_offs);
- if (!last->e_value_block && o < offs)
- last->e_value_offs =
- cpu_to_le16(o + size);
- last = EXT3_XATTR_NEXT(last);
- }
- }
- if (value == NULL) {
- /* Remove the old name. */
- size_t size = EXT3_XATTR_LEN(name_len);
- last = ENTRY((char *)last - size);
- memmove(here, (char*)here + size,
- (char*)last - (char*)here);
- memset(last, 0, size);
- }
- }
-
- if (value != NULL) {
- /* Insert the new value. */
- here->e_value_size = cpu_to_le32(value_len);
- if (value_len) {
- size_t size = EXT3_XATTR_SIZE(value_len);
- char *val = (char *)header + min_offs - size;
- here->e_value_offs =
- cpu_to_le16((char *)val - (char *)header);
- memset(val + size - EXT3_XATTR_PAD, 0,
- EXT3_XATTR_PAD); /* Clear the pad bytes. */
- memcpy(val, value, value_len);
- }
- }
-
-skip_replace:
- if (!IS_LAST_ENTRY(ENTRY(header+1)))
- ext3_xattr_rehash(header, here);
- if (bh && header == HDR(bh)) {
- /* we were modifying in-place. */
- unlock_buffer(bh);
- error = ext3_journal_dirty_metadata(handle, bh);
- if (error)
- goto cleanup;
- }
- error = ext3_xattr_set_handle2(handle, inode, bh,
- IS_LAST_ENTRY(ENTRY(header+1)) ?
- NULL : header);
-
-cleanup:
- brelse(bh);
- if (!(bh && header == HDR(bh)))
- kfree(header);
- up_write(&EXT3_I(inode)->xattr_sem);
-
- return error;
-}
-
-/*
- * Second half of ext3_xattr_set_handle(): Update the file system.
- */
-static int
-ext3_xattr_set_handle2(handle_t *handle, struct inode *inode,
- struct buffer_head *old_bh,
- struct ext3_xattr_header *header)
-{
- struct super_block *sb = inode->i_sb;
- struct buffer_head *new_bh = NULL;
- struct mb_cache_entry *ce = NULL;
- int error;
+ error = ext3_xattr_set_entry(&i, &s);
+ if (error == -EIO)
+ goto bad_block;
+ if (error)
+ goto cleanup;
+ if (!IS_LAST_ENTRY(s.first))
+ ext3_xattr_rehash(header, s.here);

- if (header) {
+inserted:
+ if (!IS_LAST_ENTRY(s.first)) {
new_bh = ext3_xattr_cache_find(inode, header, &ce);
if (new_bh) {
/* We found an identical block in the cache. */
if (new_bh == old_bh)
- ea_bdebug(new_bh, "keeping this block");
+ ea_bdebug(new_bh, "keeping");
else {
/* The old block is released after updating
the inode. */
- ea_bdebug(new_bh, "reusing block");
-
error = -EDQUOT;
if (DQUOT_ALLOC_BLOCK(inode, 1))
goto cleanup;
@@ -701,25 +694,23 @@ ext3_xattr_set_handle2(handle_t *handle,
if (error)
goto cleanup;
lock_buffer(new_bh);
- HDR(new_bh)->h_refcount = cpu_to_le32(1 +
- le32_to_cpu(HDR(new_bh)->h_refcount));
- ea_bdebug(new_bh, "refcount now=%d",
- le32_to_cpu(HDR(new_bh)->h_refcount));
+ BHDR(new_bh)->h_refcount = cpu_to_le32(1 +
+ le32_to_cpu(BHDR(new_bh)->h_refcount));
+ ea_bdebug(new_bh, "reusing; refcount now=%d",
+ le32_to_cpu(BHDR(new_bh)->h_refcount));
unlock_buffer(new_bh);
- error = ext3_journal_dirty_metadata(handle, new_bh);
+ error = ext3_journal_dirty_metadata(handle,
+ new_bh);
if (error)
goto cleanup;
}
mb_cache_entry_release(ce);
ce = NULL;
- } else if (old_bh && header == HDR(old_bh)) {
+ } else if (old_bh && header == BHDR(old_bh)) {
/* We were modifying this block in-place. */
-
- /* Keep this block. No need to lock the block as we
- * don't need to change the reference count. */
+ ea_bdebug(old_bh, "keeping this block");
new_bh = old_bh;
get_bh(new_bh);
- ext3_xattr_cache_insert(new_bh);
} else {
/* We need to allocate a new block */
int goal = le32_to_cpu(
@@ -748,11 +739,10 @@ getblk_failed:
set_buffer_uptodate(new_bh);
unlock_buffer(new_bh);
ext3_xattr_cache_insert(new_bh);
-
- ext3_xattr_update_super_block(handle, sb);
error = ext3_journal_dirty_metadata(handle, new_bh);
if (error)
goto cleanup;
+ ext3_xattr_update_super_block(handle, sb);
}
}

@@ -763,21 +753,23 @@ getblk_failed:
if (IS_SYNC(inode))
handle->h_sync = 1;

- error = 0;
- if (old_bh && old_bh != new_bh) {
- /*
- * If there was an old block, and we are no longer using it,
- * release the old block.
- */
+ /* Drop the previous xattr block. */
+ if (old_bh && old_bh != new_bh)
ext3_xattr_release_block(handle, inode, old_bh);
- }
+ error = 0;

cleanup:
if (ce)
mb_cache_entry_release(ce);
brelse(new_bh);
+ brelse(old_bh);
+ if (!(old_bh && header == BHDR(old_bh)))
+ kfree(header);
+ up_write(&EXT3_I(inode)->xattr_sem);

return error;
+
+#undef header
}

/*
@@ -832,14 +824,14 @@ ext3_xattr_delete_inode(handle_t *handle
goto cleanup;
bh = sb_bread(inode->i_sb, EXT3_I(inode)->i_file_acl);
if (!bh) {
- ext3_error(inode->i_sb, "ext3_xattr_delete_inode",
+ ext3_error(inode->i_sb, __FUNCTION__,
"inode %ld: block %d read error", inode->i_ino,
EXT3_I(inode)->i_file_acl);
goto cleanup;
}
- if (HDR(bh)->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
- HDR(bh)->h_blocks != cpu_to_le32(1)) {
- ext3_error(inode->i_sb, "ext3_xattr_delete_inode",
+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT3_XATTR_MAGIC) ||
+ BHDR(bh)->h_blocks != cpu_to_le32(1)) {
+ ext3_error(inode->i_sb, __FUNCTION__,
"inode %ld: bad block %d", inode->i_ino,
EXT3_I(inode)->i_file_acl);
goto cleanup;
@@ -871,30 +863,29 @@ ext3_xattr_put_super(struct super_block
*
* Returns 0, or a negative error number on failure.
*/
-static int
+static void
ext3_xattr_cache_insert(struct buffer_head *bh)
{
- __u32 hash = le32_to_cpu(HDR(bh)->h_hash);
+ __u32 hash = le32_to_cpu(BHDR(bh)->h_hash);
struct mb_cache_entry *ce;
int error;

ce = mb_cache_entry_alloc(ext3_xattr_cache);
- if (!ce)
- return -ENOMEM;
+ if (!ce) {
+ ea_bdebug(bh, "out of memory");
+ return;
+ }
error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash);
if (error) {
mb_cache_entry_free(ce);
if (error == -EBUSY) {
- ea_bdebug(bh, "already in cache (%d cache entries)",
- atomic_read(&ext3_xattr_cache->c_entry_count));
+ ea_bdebug(bh, "already in cache");
error = 0;
}
} else {
- ea_bdebug(bh, "inserting [%x] (%d cache entries)", (int)hash,
- atomic_read(&ext3_xattr_cache->c_entry_count));
+ ea_bdebug(bh, "inserting [%x]", (int)hash);
mb_cache_entry_release(ce);
}
- return error;
}

/*
@@ -967,16 +958,16 @@ again:
}
bh = sb_bread(inode->i_sb, ce->e_block);
if (!bh) {
- ext3_error(inode->i_sb, "ext3_xattr_cache_find",
+ ext3_error(inode->i_sb, __FUNCTION__,
"inode %ld: block %ld read error",
inode->i_ino, (unsigned long) ce->e_block);
- } else if (le32_to_cpu(HDR(bh)->h_refcount) >
+ } else if (le32_to_cpu(BHDR(bh)->h_refcount) >=
EXT3_XATTR_REFCOUNT_MAX) {
- ea_idebug(inode, "block %ld refcount %d>%d",
+ ea_idebug(inode, "block %ld refcount %d>=%d",
(unsigned long) ce->e_block,
- le32_to_cpu(HDR(bh)->h_refcount),
+ le32_to_cpu(BHDR(bh)->h_refcount),
EXT3_XATTR_REFCOUNT_MAX);
- } else if (ext3_xattr_cmp(header, HDR(bh)) == 0) {
+ } else if (ext3_xattr_cmp(header, BHDR(bh)) == 0) {
*pce = ce;
return bh;
}
--
Andreas Gruenbacher <agruen@suse.de>
SUSE Labs, SUSE LINUX PRODUCTS GMBH
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