From: Akira Fujita <[email protected]>
Interchange the data blocks of the target and temporary files
in an atomic manner.
Signed-off-by: Akira Fujita <[email protected]>
Signed-off-by: Takashi Sato <[email protected]>
--
fs/ext4/defrag.c | 55 ++++++++++++++++++++++++++++++++++++-----------------
1 files changed, 37 insertions(+), 18 deletions(-)
diff --git a/fs/ext4/defrag.c b/fs/ext4/defrag.c
index d22bec9..d9e01ea 100644
--- a/fs/ext4/defrag.c
+++ b/fs/ext4/defrag.c
@@ -392,7 +392,7 @@ static int
ext4_ext_defrag_reserve(struct inode *inode, ext4_fsblk_t goal, int len)
{
struct super_block *sb = NULL;
- handle_t *handle = NULL;
+ handle_t *handle;
struct buffer_head *bitmap_bh = NULL;
struct ext4_block_alloc_info *block_i;
struct ext4_reserve_window_node *my_rsv = NULL;
@@ -1301,11 +1301,10 @@ ext4_ext_defrag_leaf_block(handle_t *handle, struct inode *org_inode,
* Replace extents for blocks from "from" to "from + count - 1".
*/
static int
-ext4_ext_replace_branches(struct inode *org_inode, struct inode *dest_inode,
- pgoff_t from_page, pgoff_t dest_from_page,
- pgoff_t count_page, int flag)
+ext4_ext_replace_branches(handle_t *handle, struct inode *org_inode,
+ struct inode *dest_inode, pgoff_t from_page,
+ pgoff_t dest_from_page, pgoff_t count_page, int flag)
{
- handle_t *handle = NULL;
struct ext4_ext_path *org_path = NULL;
struct ext4_ext_path *dest_path = NULL;
struct ext4_extent *oext, *dext, *swap_ext;
@@ -1314,7 +1313,6 @@ ext4_ext_replace_branches(struct inode *org_inode, struct inode *dest_inode,
int err = 0;
int depth;
int replaced_count = 0;
- unsigned jnum;
from = (ext4_lblk_t)from_page <<
(PAGE_CACHE_SHIFT - dest_inode->i_blkbits);
@@ -1322,12 +1320,6 @@ ext4_ext_replace_branches(struct inode *org_inode, struct inode *dest_inode,
(PAGE_CACHE_SHIFT - dest_inode->i_blkbits);
dest_off = (ext4_lblk_t)dest_from_page <<
(PAGE_CACHE_SHIFT - dest_inode->i_blkbits);
- jnum = ext4_ext_writepage_trans_blocks(org_inode, count) + 3;
- handle = ext4_journal_start(org_inode, jnum);
- if (IS_ERR(handle)) {
- err = PTR_ERR(handle);
- goto out;
- }
/* Get the original extent for the block "from" */
org_path = ext4_ext_find_extent(org_inode, from, NULL);
@@ -1455,8 +1447,6 @@ ext4_ext_replace_branches(struct inode *org_inode, struct inode *dest_inode,
}
out:
- if (handle)
- ext4_journal_stop(handle);
if (org_path) {
ext4_ext_drop_refs(org_path);
kfree(org_path);
@@ -1686,9 +1676,22 @@ ext4_ext_defrag_partial(struct inode *tmp_inode, struct file *filp,
struct inode *inode = filp->f_dentry->d_inode;
struct address_space *mapping = inode->i_mapping;
struct page *page;
+ handle_t *handle;
pgoff_t offset_in_page = PAGE_SIZE;
+ int jblocks;
int ret = 0;
+ /*
+ * It needs twice the amount of ordinary journal buffers because
+ * inode and tmp_inode may change each different metadata blocks.
+ */
+ jblocks = ext4_writepage_trans_blocks(inode) * 2;
+ handle = ext4_journal_start(inode, jblocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ return ret;
+ }
+
up_write(&EXT4_I(inode)->i_data_sem);
page = read_cache_page(inode->i_mapping, org_offset,
(filler_t *)inode->i_mapping->a_ops->readpage, NULL);
@@ -1713,8 +1716,8 @@ ext4_ext_defrag_partial(struct inode *tmp_inode, struct file *filp,
/* release old bh and drop refs */
try_to_release_page(page, 0);
- ret = ext4_ext_replace_branches(inode, tmp_inode, org_offset,
- dest_offset, 1, flag);
+ ret = ext4_ext_replace_branches(handle, inode, tmp_inode,
+ org_offset, dest_offset, 1, flag);
if (ret < 0)
goto ERR;
@@ -1744,6 +1747,7 @@ ext4_ext_defrag_partial(struct inode *tmp_inode, struct file *filp,
ERR:
unlock_page(page);
page_cache_release(page);
+ ext4_journal_stop(handle);
return (ret < 0 ? ret : 0);
}
@@ -1766,7 +1770,9 @@ ext4_ext_defrag_partial2(struct inode *tmp_inode, struct file *filp,
struct buffer_head *bh;
struct page *page;
const struct address_space_operations *a_ops = mapping->a_ops;
+ handle_t *handle;
pgoff_t offset_in_page = PAGE_SIZE;
+ int jblocks;
int ret = 0;
int blocksize = inode->i_sb->s_blocksize;
int blocks_per_page = 0;
@@ -1776,6 +1782,17 @@ ext4_ext_defrag_partial2(struct inode *tmp_inode, struct file *filp,
unsigned int w_flags = 0;
void *fsdata;
+ /*
+ * It needs twice the amount of ordinary journal buffers because
+ * inode and tmp_inode may change each different metadata blocks.
+ */
+ jblocks = ext4_writepage_trans_blocks(inode) * 2;
+ handle = ext4_journal_start(inode, jblocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ return ret;
+ }
+
if (segment_eq(get_fs(), KERNEL_DS))
w_flags |= AOP_FLAG_UNINTERRUPTIBLE;
@@ -1815,8 +1832,8 @@ ext4_ext_defrag_partial2(struct inode *tmp_inode, struct file *filp,
/* release old bh and drop refs */
try_to_release_page(page, 0);
- ret = ext4_ext_replace_branches(inode, tmp_inode, org_offset,
- dest_offset, 1, flag);
+ ret = ext4_ext_replace_branches(handle, inode, tmp_inode,
+ org_offset, dest_offset, 1, flag);
if (ret < 0)
goto ERR;
@@ -1849,6 +1866,8 @@ ext4_ext_defrag_partial2(struct inode *tmp_inode, struct file *filp,
if (unlikely(ret < 0))
goto ERR;
ERR:
+ ext4_journal_stop(handle);
+
return (ret < 0 ? ret : 0);
}