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-rw-r--r--fs/ext3/dir.c5
-rw-r--r--fs/ext3/inode.c105
2 files changed, 79 insertions, 31 deletions
diff --git a/fs/ext3/dir.c b/fs/ext3/dir.c
index 773459164bb2..38bd3f6ec147 100644
--- a/fs/ext3/dir.c
+++ b/fs/ext3/dir.c
@@ -131,8 +131,9 @@ static int ext3_readdir(struct file * filp,
struct buffer_head *bh = NULL;
map_bh.b_state = 0;
- err = ext3_get_block_handle(NULL, inode, blk, &map_bh, 0, 0);
- if (!err) {
+ err = ext3_get_blocks_handle(NULL, inode, blk, 1,
+ &map_bh, 0, 0);
+ if (err > 0) {
page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
&filp->f_ra,
filp,
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 76e22c9c9c6c..fcfb10f77120 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -330,7 +330,7 @@ static int ext3_block_to_path(struct inode *inode,
ext3_warning (inode->i_sb, "ext3_block_to_path", "block > big");
}
if (boundary)
- *boundary = (i_block & (ptrs - 1)) == (final - 1);
+ *boundary = final - 1 - (i_block & (ptrs - 1));
return n;
}
@@ -669,11 +669,15 @@ err_out:
* akpm: `handle' can be NULL if create == 0.
*
* The BKL may not be held on entry here. Be sure to take it early.
+ * return > 0, # of blocks mapped or allocated.
+ * return = 0, if plain lookup failed.
+ * return < 0, error case.
*/
int
-ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create, int extend_disksize)
+ext3_get_blocks_handle(handle_t *handle, struct inode *inode, sector_t iblock,
+ unsigned long maxblocks, struct buffer_head *bh_result,
+ int create, int extend_disksize)
{
int err = -EIO;
int offsets[4];
@@ -681,11 +685,15 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock,
Indirect *partial;
unsigned long goal;
int left;
- int boundary = 0;
- const int depth = ext3_block_to_path(inode, iblock, offsets, &boundary);
+ int blocks_to_boundary = 0;
+ int depth;
struct ext3_inode_info *ei = EXT3_I(inode);
+ int count = 0;
+ unsigned long first_block = 0;
+
J_ASSERT(handle != NULL || create == 0);
+ depth = ext3_block_to_path(inode, iblock, offsets, &blocks_to_boundary);
if (depth == 0)
goto out;
@@ -694,8 +702,31 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock,
/* Simplest case - block found, no allocation needed */
if (!partial) {
+ first_block = chain[depth - 1].key;
clear_buffer_new(bh_result);
- goto got_it;
+ count++;
+ /*map more blocks*/
+ while (count < maxblocks && count <= blocks_to_boundary) {
+ if (!verify_chain(chain, partial)) {
+ /*
+ * Indirect block might be removed by
+ * truncate while we were reading it.
+ * Handling of that case: forget what we've
+ * got now. Flag the err as EAGAIN, so it
+ * will reread.
+ */
+ err = -EAGAIN;
+ count = 0;
+ break;
+ }
+ if (le32_to_cpu(*(chain[depth-1].p+count) ==
+ (first_block + count)))
+ count++;
+ else
+ break;
+ }
+ if (err != -EAGAIN)
+ goto got_it;
}
/* Next simple case - plain lookup or failed read of indirect block */
@@ -723,6 +754,7 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock,
}
partial = ext3_get_branch(inode, depth, offsets, chain, &err);
if (!partial) {
+ count++;
mutex_unlock(&ei->truncate_mutex);
if (err)
goto cleanup;
@@ -772,8 +804,9 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock,
set_buffer_new(bh_result);
got_it:
map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
- if (boundary)
+ if (blocks_to_boundary == 0)
set_buffer_boundary(bh_result);
+ err = count;
/* Clean up and exit */
partial = chain + depth - 1; /* the whole chain */
cleanup:
@@ -787,21 +820,6 @@ out:
return err;
}
-static int ext3_get_block(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
-{
- handle_t *handle = NULL;
- int ret;
-
- if (create) {
- handle = ext3_journal_current_handle();
- J_ASSERT(handle != 0);
- }
- ret = ext3_get_block_handle(handle, inode, iblock,
- bh_result, create, 1);
- return ret;
-}
-
#define DIO_CREDITS (EXT3_RESERVE_TRANS_BLOCKS + 32)
static int
@@ -812,9 +830,12 @@ ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock,
handle_t *handle = journal_current_handle();
int ret = 0;
- if (!handle)
+ if (!create)
goto get_block; /* A read */
+ if (max_blocks == 1)
+ goto get_block; /* A single block get */
+
if (handle->h_transaction->t_state == T_LOCKED) {
/*
* Huge direct-io writes can hold off commits for long
@@ -841,13 +862,31 @@ ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock,
}
get_block:
- if (ret == 0)
- ret = ext3_get_block_handle(handle, inode, iblock,
- bh_result, create, 0);
- bh_result->b_size = (1 << inode->i_blkbits);
+ if (ret == 0) {
+ ret = ext3_get_blocks_handle(handle, inode, iblock,
+ max_blocks, bh_result, create, 0);
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
+ }
+ }
return ret;
}
+static int ext3_get_blocks(struct inode *inode, sector_t iblock,
+ unsigned long maxblocks, struct buffer_head *bh_result,
+ int create)
+{
+ return ext3_direct_io_get_blocks(inode, iblock, maxblocks,
+ bh_result, create);
+}
+
+static int ext3_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ return ext3_get_blocks(inode, iblock, 1, bh_result, create);
+}
+
/*
* `handle' can be NULL if create is zero
*/
@@ -862,8 +901,16 @@ struct buffer_head *ext3_getblk(handle_t *handle, struct inode * inode,
dummy.b_state = 0;
dummy.b_blocknr = -1000;
buffer_trace_init(&dummy.b_history);
- *errp = ext3_get_block_handle(handle, inode, block, &dummy, create, 1);
- if (!*errp && buffer_mapped(&dummy)) {
+ err = ext3_get_blocks_handle(handle, inode, block, 1,
+ &dummy, create, 1);
+ if (err == 1) {
+ err = 0;
+ } else if (err >= 0) {
+ WARN_ON(1);
+ err = -EIO;
+ }
+ *errp = err;
+ if (!err && buffer_mapped(&dummy)) {
struct buffer_head *bh;
bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
if (!bh) {