Oops. My MUA still had the old address in it.
The reiserfs disk format is designed to handle file systems up to
2^32-1 blocks, which at 4KiB blocks means ~ 16 TiB - 4KiB.
Unfortunately, the superblock's s_bmap_nr value, which contains a
count of the number of bitmap blocks in the file system is a 16 bit
value. This limits the usable size of the file system to
8 TiB (4096^2 * 8 * 65536).
Changing the disk format this late in the game, especially with a file
system without sane superblock versioning, is a tough sell. This patch
implements the following changes:
* The s_bmap_nr value is no longer accessed directly. Instead, an
in-core 32-bit value is used instead. The real value is only
accessed directly during mount and resize.
* If the value of s_bmap_nr is valid, then the value is used as-is.
* If the value of s_bmap_nr has overflowed, the on-disk value is
zeroed out and the number of bitmaps is calculate on mount and
resize.
* Quick audit for signed int variables used to store block numbers.
The reason for zeroing it out is simple. If it has overflowed, it's
invalid anyway. Kernels mounting these file systems may end up
with unpredictible results, the most obvious of which occurs in
kernels with dynamic bitmaps: it will BUG almost immediately.
Alternatively, if the value is zeroed, the memory allocation for
tracking the bitmap blocks will end up being vmalloc(0), causing
mount to fail when a NULL pointer is returned. Since the
ZERO_SIZE_PTR changes haven't been merged in these older kernels,
the failure won't result in an Oops, just a failed mount.
A matching change for reiserfsprogs will also be submitted to support
the s_bmap_nr == 0 value as valid.
Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx>
---
fs/reiserfs/bitmap.c | 56 ++++++++++++++++++++++++-----------------
fs/reiserfs/inode.c | 12 ++++----
fs/reiserfs/journal.c | 18 +++++++------
fs/reiserfs/resize.c | 9 +++++-
fs/reiserfs/stree.c | 2 -
include/linux/reiserfs_fs.h | 3 ++
include/linux/reiserfs_fs_sb.h | 1
7 files changed, 62 insertions(+), 39 deletions(-)
--- a/fs/reiserfs/bitmap.c 2007-08-06 14:32:14.000000000 -0400
+++ b/fs/reiserfs/bitmap.c 2007-08-06 15:31:40.000000000 -0400
@@ -47,7 +47,9 @@
test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
static inline void get_bit_address(struct super_block *s,
- b_blocknr_t block, int *bmap_nr, int *offset)
+ b_blocknr_t block,
+ unsigned int *bmap_nr,
+ unsigned int *offset)
{
/* It is in the bitmap block number equal to the block
* number divided by the number of bits in a block. */
@@ -59,7 +61,7 @@ static inline void get_bit_address(struc
#ifdef CONFIG_REISERFS_CHECK
int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
{
- int bmap, offset;
+ unsigned int bmap, offset;
if (block == 0 || block >= SB_BLOCK_COUNT(s)) {
reiserfs_warning(s,
@@ -75,22 +77,23 @@ int is_reusable(struct super_block *s, b
if (unlikely(test_bit(REISERFS_OLD_FORMAT,
&(REISERFS_SB(s)->s_properties)))) {
b_blocknr_t bmap1 = REISERFS_SB(s)->s_sbh->b_blocknr + 1;
- if (block >= bmap1 && block <= bmap1 + SB_BMAP_NR(s)) {
+ if (block >= bmap1 &&
+ block <= bmap1 + REISERFS_SB(s)->s_bmap_nr) {
reiserfs_warning(s, "vs: 4019: is_reusable: "
"bitmap block %lu(%u) can't be freed or reused",
- block, SB_BMAP_NR(s));
+ block, REISERFS_SB(s)->s_bmap_nr);
return 0;
}
} else {
if (offset == 0) {
reiserfs_warning(s, "vs: 4020: is_reusable: "
"bitmap block %lu(%u) can't be freed or reused",
- block, SB_BMAP_NR(s));
+ block, REISERFS_SB(s)->s_bmap_nr);
return 0;
}
}
- if (bmap >= SB_BMAP_NR(s)) {
+ if (bmap >= REISERFS_SB(s)->s_bmap_nr) {
reiserfs_warning(s,
"vs-4030: is_reusable: there is no so many bitmap blocks: "
"block=%lu, bitmap_nr=%d", block, bmap);
@@ -143,8 +146,8 @@ static int scan_bitmap_block(struct reis
BUG_ON(!th->t_trans_id);
- RFALSE(bmap_n >= SB_BMAP_NR(s), "Bitmap %d is out of range (0..%d)",
- bmap_n, SB_BMAP_NR(s) - 1);
+ RFALSE(bmap_n >= REISERFS_SB(s)->s_bmap_nr, "Bitmap %d is out of range (0..%d)",
+ bmap_n, REISERFS_SB(s)->s_bmap_nr - 1);
PROC_INFO_INC(s, scan_bitmap.bmap);
/* this is unclear and lacks comments, explain how journal bitmaps
work here for the reader. Convey a sense of the design here. What
@@ -249,12 +252,12 @@ static int bmap_hash_id(struct super_blo
} else {
hash_in = (char *)(&id);
hash = keyed_hash(hash_in, 4);
- bm = hash % SB_BMAP_NR(s);
+ bm = hash % REISERFS_SB(s)->s_bmap_nr;
if (!bm)
bm = 1;
}
/* this can only be true when SB_BMAP_NR = 1 */
- if (bm >= SB_BMAP_NR(s))
+ if (bm >= REISERFS_SB(s)->s_bmap_nr)
bm = 0;
return bm;
}
@@ -316,9 +319,9 @@ static int scan_bitmap(struct reiserfs_t
/* find every bm and bmap and bmap_nr in this file, and change them all to bitmap_blocknr
* - Hans, it is not a block number - Zam. */
- int bm, off;
- int end_bm, end_off;
- int off_max = s->s_blocksize << 3;
+ unsigned int bm, off;
+ unsigned int end_bm, end_off;
+ unsigned int off_max = s->s_blocksize << 3;
BUG_ON(!th->t_trans_id);
@@ -328,10 +331,10 @@ static int scan_bitmap(struct reiserfs_t
get_bit_address(s, *start, &bm, &off);
get_bit_address(s, finish, &end_bm, &end_off);
- if (bm > SB_BMAP_NR(s))
+ if (bm > REISERFS_SB(s)->s_bmap_nr)
return 0;
- if (end_bm > SB_BMAP_NR(s))
- end_bm = SB_BMAP_NR(s);
+ if (end_bm > REISERFS_SB(s)->s_bmap_nr)
+ end_bm = REISERFS_SB(s)->s_bmap_nr;
/* When the bitmap is more than 10% free, anyone can allocate.
* When it's less than 10% free, only files that already use the
@@ -385,7 +388,7 @@ static void _reiserfs_free_block(struct
struct reiserfs_super_block *rs;
struct buffer_head *sbh, *bmbh;
struct reiserfs_bitmap_info *apbi;
- int nr, offset;
+ unsigned int nr, offset;
BUG_ON(!th->t_trans_id);
@@ -397,10 +400,12 @@ static void _reiserfs_free_block(struct
get_bit_address(s, block, &nr, &offset);
- if (nr >= sb_bmap_nr(rs)) {
+ if (nr >= REISERFS_SB(s)->s_bmap_nr) {
reiserfs_warning(s, "vs-4075: reiserfs_free_block: "
- "block %lu is out of range on %s",
- block, reiserfs_bdevname(s));
+ "block %lu is out of range on %s "
+ "(nr=%lu,max=%lu)", block,
+ reiserfs_bdevname(s), nr,
+ REISERFS_SB(s)->s_bmap_nr);
return;
}
@@ -1324,14 +1329,21 @@ struct buffer_head *reiserfs_read_bitmap
int reiserfs_init_bitmap_cache(struct super_block *sb)
{
struct reiserfs_bitmap_info *bitmap;
+ unsigned int blocks = SB_BLOCK_COUNT(sb);
+ unsigned int bmap_nr = blocks >> (sb->s_blocksize_bits + 3);
- bitmap = vmalloc(sizeof (*bitmap) * SB_BMAP_NR(sb));
+ if (blocks & ~(sb->s_blocksize << 3))
+ ++bmap_nr;
+
+
+ bitmap = vmalloc(sizeof (*bitmap) * bmap_nr);
if (bitmap == NULL)
return -ENOMEM;
- memset(bitmap, 0, sizeof (*bitmap) * SB_BMAP_NR(sb));
+ memset(bitmap, 0, sizeof (*bitmap) * bmap_nr);
SB_AP_BITMAP(sb) = bitmap;
+ REISERFS_SB(sb)->s_bmap_nr = bmap_nr;
return 0;
}
--- a/fs/reiserfs/inode.c 2007-08-06 14:32:14.000000000 -0400
+++ b/fs/reiserfs/inode.c 2007-08-06 15:03:04.000000000 -0400
@@ -197,7 +197,7 @@ static inline void set_block_dev_mapped(
// files which were created in the earlier version can not be longer,
// than 2 gb
//
-static int file_capable(struct inode *inode, long block)
+static int file_capable(struct inode *inode, unsigned int block)
{
if (get_inode_item_key_version(inode) != KEY_FORMAT_3_5 || // it is new file.
block < (1 << (31 - inode->i_sb->s_blocksize_bits))) // old file, but 'block' is inside of 2gb
@@ -240,7 +240,7 @@ static int file_capable(struct inode *in
// Please improve the english/clarity in the comment above, as it is
// hard to understand.
-static int _get_block_create_0(struct inode *inode, long block,
+static int _get_block_create_0(struct inode *inode, unsigned int block,
struct buffer_head *bh_result, int args)
{
INITIALIZE_PATH(path);
@@ -248,7 +248,7 @@ static int _get_block_create_0(struct in
struct buffer_head *bh;
struct item_head *ih, tmp_ih;
int fs_gen;
- int blocknr;
+ unsigned int blocknr;
char *p = NULL;
int chars;
int ret;
@@ -567,7 +567,7 @@ static int convert_tail_for_hole(struct
}
static inline int _allocate_block(struct reiserfs_transaction_handle *th,
- long block,
+ unsigned int block,
struct inode *inode,
b_blocknr_t * allocated_block_nr,
struct treepath *path, int flags)
@@ -1068,8 +1068,8 @@ static int real_space_diff(struct inode
return bytes;
}
-static inline loff_t to_real_used_space(struct inode *inode, ulong blocks,
- int sd_size)
+static inline loff_t to_real_used_space(struct inode *inode,
+ unsigned int blocks, int sd_size)
{
if (S_ISLNK(inode->i_mode) || S_ISDIR(inode->i_mode)) {
return inode->i_size +
--- a/fs/reiserfs/journal.c 2007-08-06 14:32:14.000000000 -0400
+++ b/fs/reiserfs/journal.c 2007-08-06 15:09:13.000000000 -0400
@@ -219,11 +219,12 @@ static void allocate_bitmap_nodes(struct
}
}
-static int set_bit_in_list_bitmap(struct super_block *p_s_sb, int block,
+static int set_bit_in_list_bitmap(struct super_block *p_s_sb,
+ unsigned int block,
struct reiserfs_list_bitmap *jb)
{
- int bmap_nr = block / (p_s_sb->s_blocksize << 3);
- int bit_nr = block % (p_s_sb->s_blocksize << 3);
+ unsigned int bmap_nr = block / (p_s_sb->s_blocksize << 3);
+ unsigned int bit_nr = block % (p_s_sb->s_blocksize << 3);
if (!jb->bitmaps[bmap_nr]) {
jb->bitmaps[bmap_nr] = get_bitmap_node(p_s_sb);
@@ -239,7 +240,7 @@ static void cleanup_bitmap_list(struct s
if (jb->bitmaps == NULL)
return;
- for (i = 0; i < SB_BMAP_NR(p_s_sb); i++) {
+ for (i = 0; i < REISERFS_SB(p_s_sb)->s_bmap_nr; i++) {
if (jb->bitmaps[i]) {
free_bitmap_node(p_s_sb, jb->bitmaps[i]);
jb->bitmaps[i] = NULL;
@@ -2279,8 +2280,9 @@ static int journal_read_transaction(stru
Right now it is only used from journal code. But later we might use it
from other places.
Note: Do not use journal_getblk/sb_getblk functions here! */
-static struct buffer_head *reiserfs_breada(struct block_device *dev, int block,
- int bufsize, unsigned int max_block)
+static struct buffer_head *reiserfs_breada(struct block_device *dev,
+ unsigned int block, int bufsize,
+ unsigned int max_block)
{
struct buffer_head *bhlist[BUFNR];
unsigned int blocks = BUFNR;
@@ -2649,7 +2651,7 @@ int journal_init(struct super_block *p_s
journal->j_persistent_trans = 0;
if (reiserfs_allocate_list_bitmaps(p_s_sb,
journal->j_list_bitmap,
- SB_BMAP_NR(p_s_sb)))
+ REISERFS_SB(p_s_sb)->s_bmap_nr))
goto free_and_return;
allocate_bitmap_nodes(p_s_sb);
@@ -2657,7 +2659,7 @@ int journal_init(struct super_block *p_s
SB_JOURNAL_1st_RESERVED_BLOCK(p_s_sb) = (old_format ?
REISERFS_OLD_DISK_OFFSET_IN_BYTES
/ p_s_sb->s_blocksize +
- SB_BMAP_NR(p_s_sb) +
+ REISERFS_SB(p_s_sb)->s_bmap_nr +
1 :
REISERFS_DISK_OFFSET_IN_BYTES /
p_s_sb->s_blocksize + 2);
--- a/fs/reiserfs/resize.c 2007-08-06 14:32:14.000000000 -0400
+++ b/fs/reiserfs/resize.c 2007-08-06 15:12:04.000000000 -0400
@@ -61,7 +61,7 @@ int reiserfs_resize(struct super_block *
}
/* count used bits in last bitmap block */
- block_r = SB_BLOCK_COUNT(s) - (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8;
+ block_r = SB_BLOCK_COUNT(s) - (REISERFS_SB(s)->s_bmap_nr - 1) * s->s_blocksize * 8;
/* count bitmap blocks in new fs */
bmap_nr_new = block_count_new / (s->s_blocksize * 8);
@@ -73,7 +73,7 @@ int reiserfs_resize(struct super_block *
/* save old values */
block_count = SB_BLOCK_COUNT(s);
- bmap_nr = SB_BMAP_NR(s);
+ bmap_nr = REISERFS_SB(s)->s_bmap_nr;
/* resizing of reiserfs bitmaps (journal and real), if needed */
if (bmap_nr_new > bmap_nr) {
@@ -206,6 +206,11 @@ int reiserfs_resize(struct super_block *
free_blocks + (block_count_new - block_count -
(bmap_nr_new - bmap_nr)));
PUT_SB_BLOCK_COUNT(s, block_count_new);
+
+ REISERFS_SB(s)->s_bmap_nr = bmap_nr_new;
+ if (bmap_would_wrap(bmap_nr_new))
+ bmap_nr_new = 0;
+
PUT_SB_BMAP_NR(s, bmap_nr_new);
s->s_dirt = 1;
--- a/fs/reiserfs/stree.c 2007-08-06 14:32:14.000000000 -0400
+++ b/fs/reiserfs/stree.c 2007-08-06 14:44:46.000000000 -0400
@@ -611,7 +611,7 @@ int search_by_key(struct super_block *p_
DISK_LEAF_NODE_LEVEL */
)
{
- int n_block_number;
+ unsigned int n_block_number;
int expected_level;
struct buffer_head *p_s_bh;
struct path_element *p_s_last_element;
--- a/include/linux/reiserfs_fs.h 2007-08-06 14:32:14.000000000 -0400
+++ b/include/linux/reiserfs_fs.h 2007-08-06 15:38:37.000000000 -0400
@@ -229,6 +229,9 @@ struct reiserfs_super_block {
((!is_reiserfs_jr(SB_DISK_SUPER_BLOCK(s)) ? \
SB_ONDISK_JOURNAL_SIZE(s) + 1 : SB_ONDISK_RESERVED_FOR_JOURNAL(s)))
+/* s_bmap_nr is a u16 */
+#define bmap_would_wrap(n) (n >= 65536)
+
int is_reiserfs_3_5(struct reiserfs_super_block *rs);
int is_reiserfs_3_6(struct reiserfs_super_block *rs);
int is_reiserfs_jr(struct reiserfs_super_block *rs);
--- a/include/linux/reiserfs_fs_sb.h 2007-08-06 14:32:14.000000000 -0400
+++ b/include/linux/reiserfs_fs_sb.h 2007-08-06 14:44:46.000000000 -0400
@@ -410,6 +410,7 @@ struct reiserfs_sb_info {
char *s_qf_names[MAXQUOTAS];
int s_jquota_fmt;
#endif
+ unsigned int s_bmap_nr;
};
/* Definitions of reiserfs on-disk properties: */
--
Jeff Mahoney
SUSE Labs
-
To unsubscribe from this list: send the line "unsubscribe reiserfs-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
