* [patch 076/120] Fix 64KB blocksize in ext3 directories
@ 2007-11-15 1:00 akpm
0 siblings, 0 replies; only message in thread
From: akpm @ 2007-11-15 1:00 UTC (permalink / raw)
To: torvalds; +Cc: akpm, jack, linux-ext4
From: Jan Kara <jack@suse.cz>
With 64KB blocksize, a directory entry can have size 64KB which does not
fit into 16 bits we have for entry lenght. So we store 0xffff instead and
convert value when read from / written to disk. The patch also converts
some places to use ext3_next_entry() when we are changing them anyway.
[akpm@linux-foundation.org: coding-style cleanups]
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
fs/ext3/dir.c | 10 ++--
fs/ext3/namei.c | 92 ++++++++++++++++++--------------------
include/linux/ext3_fs.h | 20 ++++++++
3 files changed, 70 insertions(+), 52 deletions(-)
diff -puN fs/ext3/dir.c~fix-64kb-blocksize-in-ext3-directories fs/ext3/dir.c
--- a/fs/ext3/dir.c~fix-64kb-blocksize-in-ext3-directories
+++ a/fs/ext3/dir.c
@@ -67,7 +67,7 @@ int ext3_check_dir_entry (const char * f
unsigned long offset)
{
const char * error_msg = NULL;
- const int rlen = le16_to_cpu(de->rec_len);
+ const int rlen = ext3_rec_len_from_disk(de->rec_len);
if (rlen < EXT3_DIR_REC_LEN(1))
error_msg = "rec_len is smaller than minimal";
@@ -173,10 +173,10 @@ revalidate:
* least that it is non-zero. A
* failure will be detected in the
* dirent test below. */
- if (le16_to_cpu(de->rec_len) <
+ if (ext3_rec_len_from_disk(de->rec_len) <
EXT3_DIR_REC_LEN(1))
break;
- i += le16_to_cpu(de->rec_len);
+ i += ext3_rec_len_from_disk(de->rec_len);
}
offset = i;
filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
@@ -197,7 +197,7 @@ revalidate:
ret = stored;
goto out;
}
- offset += le16_to_cpu(de->rec_len);
+ offset += ext3_rec_len_from_disk(de->rec_len);
if (le32_to_cpu(de->inode)) {
/* We might block in the next section
* if the data destination is
@@ -219,7 +219,7 @@ revalidate:
goto revalidate;
stored ++;
}
- filp->f_pos += le16_to_cpu(de->rec_len);
+ filp->f_pos += ext3_rec_len_from_disk(de->rec_len);
}
offset = 0;
brelse (bh);
diff -puN fs/ext3/namei.c~fix-64kb-blocksize-in-ext3-directories fs/ext3/namei.c
--- a/fs/ext3/namei.c~fix-64kb-blocksize-in-ext3-directories
+++ a/fs/ext3/namei.c
@@ -177,6 +177,16 @@ static int ext3_dx_add_entry(handle_t *h
struct inode *inode);
/*
+ * p is at least 6 bytes before the end of page
+ */
+static inline struct ext3_dir_entry_2 *
+ext3_next_entry(struct ext3_dir_entry_2 *p)
+{
+ return (struct ext3_dir_entry_2 *)((char *)p +
+ ext3_rec_len_from_disk(p->rec_len));
+}
+
+/*
* Future: use high four bits of block for coalesce-on-delete flags
* Mask them off for now.
*/
@@ -280,7 +290,7 @@ static struct stats dx_show_leaf(struct
space += EXT3_DIR_REC_LEN(de->name_len);
names++;
}
- de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
+ de = ext3_next_entry(de);
}
printk("(%i)\n", names);
return (struct stats) { names, space, 1 };
@@ -547,14 +557,6 @@ static int ext3_htree_next_block(struct
/*
- * p is at least 6 bytes before the end of page
- */
-static inline struct ext3_dir_entry_2 *ext3_next_entry(struct ext3_dir_entry_2 *p)
-{
- return (struct ext3_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
-}
-
-/*
* This function fills a red-black tree with information from a
* directory block. It returns the number directory entries loaded
* into the tree. If there is an error it is returned in err.
@@ -720,7 +722,7 @@ static int dx_make_map (struct ext3_dir_
cond_resched();
}
/* XXX: do we need to check rec_len == 0 case? -Chris */
- de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
+ de = ext3_next_entry(de);
}
return count;
}
@@ -822,7 +824,7 @@ static inline int search_dirblock(struct
return 1;
}
/* prevent looping on a bad block */
- de_len = le16_to_cpu(de->rec_len);
+ de_len = ext3_rec_len_from_disk(de->rec_len);
if (de_len <= 0)
return -1;
offset += de_len;
@@ -1130,7 +1132,7 @@ dx_move_dirents(char *from, char *to, st
rec_len = EXT3_DIR_REC_LEN(de->name_len);
memcpy (to, de, rec_len);
((struct ext3_dir_entry_2 *) to)->rec_len =
- cpu_to_le16(rec_len);
+ ext3_rec_len_to_disk(rec_len);
de->inode = 0;
map++;
to += rec_len;
@@ -1149,13 +1151,12 @@ static struct ext3_dir_entry_2* dx_pack_
prev = to = de;
while ((char*)de < base + size) {
- next = (struct ext3_dir_entry_2 *) ((char *) de +
- le16_to_cpu(de->rec_len));
+ next = ext3_next_entry(de);
if (de->inode && de->name_len) {
rec_len = EXT3_DIR_REC_LEN(de->name_len);
if (de > to)
memmove(to, de, rec_len);
- to->rec_len = cpu_to_le16(rec_len);
+ to->rec_len = ext3_rec_len_to_disk(rec_len);
prev = to;
to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len);
}
@@ -1229,8 +1230,8 @@ static struct ext3_dir_entry_2 *do_split
/* Fancy dance to stay within two buffers */
de2 = dx_move_dirents(data1, data2, map + split, count - split);
de = dx_pack_dirents(data1,blocksize);
- de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
- de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
+ de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
+ de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2);
dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1));
dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1));
@@ -1300,7 +1301,7 @@ static int add_dirent_to_buf(handle_t *h
return -EEXIST;
}
nlen = EXT3_DIR_REC_LEN(de->name_len);
- rlen = le16_to_cpu(de->rec_len);
+ rlen = ext3_rec_len_from_disk(de->rec_len);
if ((de->inode? rlen - nlen: rlen) >= reclen)
break;
de = (struct ext3_dir_entry_2 *)((char *)de + rlen);
@@ -1319,11 +1320,11 @@ static int add_dirent_to_buf(handle_t *h
/* By now the buffer is marked for journaling */
nlen = EXT3_DIR_REC_LEN(de->name_len);
- rlen = le16_to_cpu(de->rec_len);
+ rlen = ext3_rec_len_from_disk(de->rec_len);
if (de->inode) {
struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen);
- de1->rec_len = cpu_to_le16(rlen - nlen);
- de->rec_len = cpu_to_le16(nlen);
+ de1->rec_len = ext3_rec_len_to_disk(rlen - nlen);
+ de->rec_len = ext3_rec_len_to_disk(nlen);
de = de1;
}
de->file_type = EXT3_FT_UNKNOWN;
@@ -1400,17 +1401,18 @@ static int make_indexed_dir(handle_t *ha
/* The 0th block becomes the root, move the dirents out */
fde = &root->dotdot;
- de = (struct ext3_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
+ de = (struct ext3_dir_entry_2 *)((char *)fde +
+ ext3_rec_len_from_disk(fde->rec_len));
len = ((char *) root) + blocksize - (char *) de;
memcpy (data1, de, len);
de = (struct ext3_dir_entry_2 *) data1;
top = data1 + len;
- while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
+ while ((char *)(de2 = ext3_next_entry(de)) < top)
de = de2;
- de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
+ de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
/* Initialize the root; the dot dirents already exist */
de = (struct ext3_dir_entry_2 *) (&root->dotdot);
- de->rec_len = cpu_to_le16(blocksize - EXT3_DIR_REC_LEN(2));
+ de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2));
memset (&root->info, 0, sizeof(root->info));
root->info.info_length = sizeof(root->info);
root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
@@ -1490,7 +1492,7 @@ static int ext3_add_entry (handle_t *han
return retval;
de = (struct ext3_dir_entry_2 *) bh->b_data;
de->inode = 0;
- de->rec_len = cpu_to_le16(blocksize);
+ de->rec_len = ext3_rec_len_to_disk(blocksize);
return add_dirent_to_buf(handle, dentry, inode, de, bh);
}
@@ -1553,7 +1555,7 @@ static int ext3_dx_add_entry(handle_t *h
goto cleanup;
node2 = (struct dx_node *)(bh2->b_data);
entries2 = node2->entries;
- node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
+ node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize);
node2->fake.inode = 0;
BUFFER_TRACE(frame->bh, "get_write_access");
err = ext3_journal_get_write_access(handle, frame->bh);
@@ -1651,9 +1653,9 @@ static int ext3_delete_entry (handle_t *
BUFFER_TRACE(bh, "get_write_access");
ext3_journal_get_write_access(handle, bh);
if (pde)
- pde->rec_len =
- cpu_to_le16(le16_to_cpu(pde->rec_len) +
- le16_to_cpu(de->rec_len));
+ pde->rec_len = ext3_rec_len_to_disk(
+ ext3_rec_len_from_disk(pde->rec_len) +
+ ext3_rec_len_from_disk(de->rec_len));
else
de->inode = 0;
dir->i_version++;
@@ -1661,10 +1663,9 @@ static int ext3_delete_entry (handle_t *
ext3_journal_dirty_metadata(handle, bh);
return 0;
}
- i += le16_to_cpu(de->rec_len);
+ i += ext3_rec_len_from_disk(de->rec_len);
pde = de;
- de = (struct ext3_dir_entry_2 *)
- ((char *) de + le16_to_cpu(de->rec_len));
+ de = ext3_next_entry(de);
}
return -ENOENT;
}
@@ -1798,13 +1799,13 @@ retry:
de = (struct ext3_dir_entry_2 *) dir_block->b_data;
de->inode = cpu_to_le32(inode->i_ino);
de->name_len = 1;
- de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len));
+ de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len));
strcpy (de->name, ".");
ext3_set_de_type(dir->i_sb, de, S_IFDIR);
- de = (struct ext3_dir_entry_2 *)
- ((char *) de + le16_to_cpu(de->rec_len));
+ de = ext3_next_entry(de);
de->inode = cpu_to_le32(dir->i_ino);
- de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1));
+ de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize -
+ EXT3_DIR_REC_LEN(1));
de->name_len = 2;
strcpy (de->name, "..");
ext3_set_de_type(dir->i_sb, de, S_IFDIR);
@@ -1856,8 +1857,7 @@ static int empty_dir (struct inode * ino
return 1;
}
de = (struct ext3_dir_entry_2 *) bh->b_data;
- de1 = (struct ext3_dir_entry_2 *)
- ((char *) de + le16_to_cpu(de->rec_len));
+ de1 = ext3_next_entry(de);
if (le32_to_cpu(de->inode) != inode->i_ino ||
!le32_to_cpu(de1->inode) ||
strcmp (".", de->name) ||
@@ -1868,9 +1868,9 @@ static int empty_dir (struct inode * ino
brelse (bh);
return 1;
}
- offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
- de = (struct ext3_dir_entry_2 *)
- ((char *) de1 + le16_to_cpu(de1->rec_len));
+ offset = ext3_rec_len_from_disk(de->rec_len) +
+ ext3_rec_len_from_disk(de1->rec_len);
+ de = ext3_next_entry(de1);
while (offset < inode->i_size ) {
if (!bh ||
(void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
@@ -1899,9 +1899,8 @@ static int empty_dir (struct inode * ino
brelse (bh);
return 0;
}
- offset += le16_to_cpu(de->rec_len);
- de = (struct ext3_dir_entry_2 *)
- ((char *) de + le16_to_cpu(de->rec_len));
+ offset += ext3_rec_len_from_disk(de->rec_len);
+ de = ext3_next_entry(de);
}
brelse (bh);
return 1;
@@ -2255,8 +2254,7 @@ retry:
}
#define PARENT_INO(buffer) \
- ((struct ext3_dir_entry_2 *) ((char *) buffer + \
- le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode
+ (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode)
/*
* Anybody can rename anything with this: the permission checks are left to the
diff -puN include/linux/ext3_fs.h~fix-64kb-blocksize-in-ext3-directories include/linux/ext3_fs.h
--- a/include/linux/ext3_fs.h~fix-64kb-blocksize-in-ext3-directories
+++ a/include/linux/ext3_fs.h
@@ -656,6 +656,26 @@ struct ext3_dir_entry_2 {
#define EXT3_DIR_ROUND (EXT3_DIR_PAD - 1)
#define EXT3_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT3_DIR_ROUND) & \
~EXT3_DIR_ROUND)
+#define EXT3_MAX_REC_LEN ((1<<16)-1)
+
+static inline unsigned ext3_rec_len_from_disk(__le16 dlen)
+{
+ unsigned len = le16_to_cpu(dlen);
+
+ if (len == EXT3_MAX_REC_LEN)
+ return 1 << 16;
+ return len;
+}
+
+static inline __le16 ext3_rec_len_to_disk(unsigned len)
+{
+ if (len == (1 << 16))
+ return cpu_to_le16(EXT3_MAX_REC_LEN);
+ else if (len > (1 << 16))
+ BUG();
+ return cpu_to_le16(len);
+}
+
/*
* Hash Tree Directory indexing
* (c) Daniel Phillips, 2001
_
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2007-11-15 1:07 UTC | newest]
Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2007-11-15 1:00 [patch 076/120] Fix 64KB blocksize in ext3 directories akpm
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.