* Copyright (C) 1991, 1992 Linus Torvalds
*
* Goal-directed block allocation by Stephen Tweedie
- * (sct@redhat.com), 1993, 1998
+ * (sct@redhat.com), 1993, 1998
* Big-endian to little-endian byte-swapping/bitmaps by
* David S. Miller (davem@caip.rutgers.edu), 1995
* 64-bit file support on 64-bit platforms by Jakub Jelinek
- * (jj@sunsite.ms.mff.cuni.cz)
+ * (jj@sunsite.ms.mff.cuni.cz)
*
* Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000
*/
#include <linux/writeback.h>
#include <linux/mpage.h>
#include <linux/uio.h>
+#include <linux/bio.h>
#include "xattr.h"
#include "acl.h"
/*
* The ext3 forget function must perform a revoke if we are freeing data
* which has been journaled. Metadata (eg. indirect blocks) must be
- * revoked in all cases.
+ * revoked in all cases.
*
* "bh" may be NULL: a metadata block may have been freed from memory
* but there may still be a record of it in the journal, and that record
* Work out how many blocks we need to proceed with the next chunk of a
* truncate transaction.
*/
-static unsigned long blocks_for_truncate(struct inode *inode)
+static unsigned long blocks_for_truncate(struct inode *inode)
{
unsigned long needed;
/* But we need to bound the transaction so we don't overflow the
* journal. */
- if (needed > EXT3_MAX_TRANS_DATA)
+ if (needed > EXT3_MAX_TRANS_DATA)
needed = EXT3_MAX_TRANS_DATA;
return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
}
-/*
+/*
* Truncate transactions can be complex and absolutely huge. So we need to
* be able to restart the transaction at a conventient checkpoint to make
* sure we don't overflow the journal.
* start_transaction gets us a new handle for a truncate transaction,
* and extend_transaction tries to extend the existing one a bit. If
* extend fails, we need to propagate the failure up and restart the
- * transaction in the top-level truncate loop. --sct
+ * transaction in the top-level truncate loop. --sct
*/
-static handle_t *start_transaction(struct inode *inode)
+static handle_t *start_transaction(struct inode *inode)
{
handle_t *result;
ext3_orphan_del(handle, inode);
EXT3_I(inode)->i_dtime = get_seconds();
- /*
+ /*
* One subtle ordering requirement: if anything has gone wrong
* (transaction abort, IO errors, whatever), then we can still
* do these next steps (the fs will already have been marked as
* having errors), but we can't free the inode if the mark_dirty
- * fails.
+ * fails.
*/
if (ext3_mark_inode_dirty(handle, inode))
/* If that failed, just do the required in-core inode clear. */
* + if there is a block to the left of our position - allocate near it.
* + if pointer will live in indirect block - allocate near that block.
* + if pointer will live in inode - allocate in the same
- * cylinder group.
+ * cylinder group.
*
* In the latter case we colour the starting block by the callers PID to
* prevent it from clashing with concurrent allocations for a different inode
* ext3_blks_to_allocate: Look up the block map and count the number
* of direct blocks need to be allocated for the given branch.
*
- * @branch: chain of indirect blocks
+ * @branch: chain of indirect blocks
* @k: number of blocks need for indirect blocks
* @blks: number of data blocks to be mapped.
* @blocks_to_boundary: the offset in the indirect block
jbd_debug(5, "splicing indirect only\n");
BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata");
err = ext3_journal_dirty_metadata(handle, where->bh);
- if (err)
+ if (err)
goto err_out;
} else {
/*
set_buffer_new(bh_result);
got_it:
map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
- if (blocks_to_boundary == 0)
+ if (count > blocks_to_boundary)
set_buffer_boundary(bh_result);
err = count;
/* Clean up and exit */
static int ext3_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
{
- handle_t *handle = journal_current_handle();
+ handle_t *handle = ext3_journal_current_handle();
int ret = 0;
unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
return bh;
if (buffer_uptodate(bh))
return bh;
- ll_rw_block(READ, 1, &bh);
+ ll_rw_block(READ_META, 1, &bh);
wait_on_buffer(bh);
if (buffer_uptodate(bh))
return bh;
for ( bh = head, block_start = 0;
ret == 0 && (bh != head || !block_start);
- block_start = block_end, bh = next)
+ block_start = block_end, bh = next)
{
next = bh->b_this_page;
block_end = block_start + blocksize;
* So what we do is to rely on the fact that journal_stop/journal_start
* will _not_ run commit under these circumstances because handle->h_ref
* is elevated. We'll still have enough credits for the tiny quotafile
- * write.
+ * write.
*/
static int do_journal_get_write_access(handle_t *handle,
struct buffer_head *bh)
return ext3_journal_get_write_access(handle, bh);
}
+/*
+ * The idea of this helper function is following:
+ * if prepare_write has allocated some blocks, but not all of them, the
+ * transaction must include the content of the newly allocated blocks.
+ * This content is expected to be set to zeroes by block_prepare_write().
+ * 2006/10/14 SAW
+ */
+static int ext3_prepare_failure(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct address_space *mapping;
+ struct buffer_head *bh, *head, *next;
+ unsigned block_start, block_end;
+ unsigned blocksize;
+ int ret;
+ handle_t *handle = ext3_journal_current_handle();
+
+ mapping = page->mapping;
+ if (ext3_should_writeback_data(mapping->host)) {
+ /* optimization: no constraints about data */
+skip:
+ return ext3_journal_stop(handle);
+ }
+
+ head = page_buffers(page);
+ blocksize = head->b_size;
+ for ( bh = head, block_start = 0;
+ bh != head || !block_start;
+ block_start = block_end, bh = next)
+ {
+ next = bh->b_this_page;
+ block_end = block_start + blocksize;
+ if (block_end <= from)
+ continue;
+ if (block_start >= to) {
+ block_start = to;
+ break;
+ }
+ if (!buffer_mapped(bh))
+ /* prepare_write failed on this bh */
+ break;
+ if (ext3_should_journal_data(mapping->host)) {
+ ret = do_journal_get_write_access(handle, bh);
+ if (ret) {
+ ext3_journal_stop(handle);
+ return ret;
+ }
+ }
+ /*
+ * block_start here becomes the first block where the current iteration
+ * of prepare_write failed.
+ */
+ }
+ if (block_start <= from)
+ goto skip;
+
+ /* commit allocated and zeroed buffers */
+ return mapping->a_ops->commit_write(file, page, from, block_start);
+}
+
static int ext3_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
struct inode *inode = page->mapping->host;
- int ret, needed_blocks = ext3_writepage_trans_blocks(inode);
+ int ret, ret2;
+ int needed_blocks = ext3_writepage_trans_blocks(inode);
handle_t *handle;
int retries = 0;
retry:
handle = ext3_journal_start(inode, needed_blocks);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out;
- }
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode))
ret = nobh_prepare_write(page, from, to, ext3_get_block);
else
ret = block_prepare_write(page, from, to, ext3_get_block);
if (ret)
- goto prepare_write_failed;
+ goto failure;
if (ext3_should_journal_data(inode)) {
ret = walk_page_buffers(handle, page_buffers(page),
from, to, NULL, do_journal_get_write_access);
+ if (ret)
+ /* fatal error, just put the handle and return */
+ journal_stop(handle);
}
-prepare_write_failed:
- if (ret)
- ext3_journal_stop(handle);
+ return ret;
+
+failure:
+ ret2 = ext3_prepare_failure(file, page, from, to);
+ if (ret2 < 0)
+ return ret2;
if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
goto retry;
-out:
+ /* retry number exceeded, or other error like -EDQUOT */
return ret;
}
if (inode->i_size > EXT3_I(inode)->i_disksize) {
EXT3_I(inode)->i_disksize = inode->i_size;
ret2 = ext3_mark_inode_dirty(handle, inode);
- if (!ret)
+ if (!ret)
ret = ret2;
}
ret2 = ext3_journal_stop(handle);
return ret;
}
-/*
+/*
* bmap() is special. It gets used by applications such as lilo and by
* the swapper to find the on-disk block of a specific piece of data.
*
* filesystem and enables swap, then they may get a nasty shock when the
* data getting swapped to that swapfile suddenly gets overwritten by
* the original zero's written out previously to the journal and
- * awaiting writeback in the kernel's buffer cache.
+ * awaiting writeback in the kernel's buffer cache.
*
* So, if we see any bmap calls here on a modified, data-journaled file,
- * take extra steps to flush any blocks which might be in the cache.
+ * take extra steps to flush any blocks which might be in the cache.
*/
static sector_t ext3_bmap(struct address_space *mapping, sector_t block)
{
int err;
if (EXT3_I(inode)->i_state & EXT3_STATE_JDATA) {
- /*
+ /*
* This is a REALLY heavyweight approach, but the use of
* bmap on dirty files is expected to be extremely rare:
* only if we run lilo or swapon on a freshly made file
- * do we expect this to happen.
+ * do we expect this to happen.
*
* (bmap requires CAP_SYS_RAWIO so this does not
* represent an unprivileged user DOS attack --- we'd be
* in trouble if mortal users could trigger this path at
- * will.)
+ * will.)
*
* NB. EXT3_STATE_JDATA is not set on files other than
* regular files. If somebody wants to bmap a directory
*/
/*
- * And attach them to the current transaction. But only if
+ * And attach them to the current transaction. But only if
* block_write_full_page() succeeded. Otherwise they are unmapped,
* and generally junk.
*/
}
}
- ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
+ ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
offset, nr_segs,
ext3_get_block, NULL);
/*
* Reacquire the handle: ext3_get_block() can restart the transaction
*/
- handle = journal_current_handle();
+ handle = ext3_journal_current_handle();
out_stop:
if (handle) {
__le32 *first, __le32 *last)
{
ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */
- unsigned long count = 0; /* Number of blocks in the run */
+ unsigned long count = 0; /* Number of blocks in the run */
__le32 *block_to_free_p = NULL; /* Pointer into inode/ind
corresponding to
block_to_free */
} else if (nr == block_to_free + count) {
count++;
} else {
- ext3_clear_blocks(handle, inode, this_bh,
+ ext3_clear_blocks(handle, inode, this_bh,
block_to_free,
count, block_to_free_p, p);
block_to_free = nr;
*/
if (!bh) {
ext3_error(inode->i_sb, "ext3_free_branches",
- "Read failure, inode=%ld, block="E3FSBLK,
+ "Read failure, inode=%lu, block="E3FSBLK,
inode->i_ino, nr);
continue;
}
*p = 0;
BUFFER_TRACE(parent_bh,
"call ext3_journal_dirty_metadata");
- ext3_journal_dirty_metadata(handle,
+ ext3_journal_dirty_metadata(handle,
parent_bh);
}
}
*/
get_bh(bh);
bh->b_end_io = end_buffer_read_sync;
- submit_bh(READ, bh);
+ submit_bh(READ_META, bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
ext3_error(inode->i_sb, "ext3_get_inode_loc",
* recovery code: that's fine, we're about to complete
* the process of deleting those. */
}
- inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size
- * (for stat), not the fs block
- * size */
inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
#ifdef EXT3_FRAGMENTS
if (raw_inode->i_block[0])
init_special_inode(inode, inode->i_mode,
old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
- else
+ else
init_special_inode(inode, inode->i_mode,
new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
}
*
* The caller must have write access to iloc->bh.
*/
-static int ext3_do_update_inode(handle_t *handle,
- struct inode *inode,
+static int ext3_do_update_inode(handle_t *handle,
+ struct inode *inode,
struct ext3_iloc *iloc)
{
struct ext3_inode *raw_inode = ext3_raw_inode(iloc);
* commit will leave the blocks being flushed in an unused state on
* disk. (On recovery, the inode will get truncated and the blocks will
* be freed, so we have a strong guarantee that no future commit will
- * leave these blocks visible to the user.)
+ * leave these blocks visible to the user.)
*
* Called with inode->sem down.
*/
return err;
}
-/*
+/*
* On success, We end up with an outstanding reference count against
- * iloc->bh. This _must_ be cleaned up later.
+ * iloc->bh. This _must_ be cleaned up later.
*/
int
-ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
+ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
struct ext3_iloc *iloc)
{
int err = 0;
}
#if 0
-/*
+/*
* Bind an inode's backing buffer_head into this transaction, to prevent
* it from being flushed to disk early. Unlike
* ext3_reserve_inode_write, this leaves behind no bh reference and
BUFFER_TRACE(iloc.bh, "get_write_access");
err = journal_get_write_access(handle, iloc.bh);
if (!err)
- err = ext3_journal_dirty_metadata(handle,
+ err = ext3_journal_dirty_metadata(handle,
iloc.bh);
brelse(iloc.bh);
}
projects / linux-drm-fsl-dcu.git / blobdiff