summaryrefslogtreecommitdiff
path: root/fs/ext4/extents.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ext4/extents.c')
-rw-r--r--fs/ext4/extents.c149
1 files changed, 93 insertions, 56 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index fb0f99dc8c22..0e8708b77da6 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -100,29 +100,41 @@ static int ext4_split_extent_at(handle_t *handle,
static int ext4_find_delayed_extent(struct inode *inode,
struct extent_status *newes);
-static int ext4_ext_truncate_extend_restart(handle_t *handle,
- struct inode *inode,
- int needed)
+static int ext4_ext_trunc_restart_fn(struct inode *inode, int *dropped)
{
- int err;
-
- if (!ext4_handle_valid(handle))
- return 0;
- if (handle->h_buffer_credits >= needed)
- return 0;
/*
- * If we need to extend the journal get a few extra blocks
- * while we're at it for efficiency's sake.
+ * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
+ * moment, get_block can be called only for blocks inside i_size since
+ * page cache has been already dropped and writes are blocked by
+ * i_mutex. So we can safely drop the i_data_sem here.
*/
- needed += 3;
- err = ext4_journal_extend(handle, needed - handle->h_buffer_credits);
- if (err <= 0)
- return err;
- err = ext4_truncate_restart_trans(handle, inode, needed);
- if (err == 0)
- err = -EAGAIN;
+ BUG_ON(EXT4_JOURNAL(inode) == NULL);
+ ext4_discard_preallocations(inode);
+ up_write(&EXT4_I(inode)->i_data_sem);
+ *dropped = 1;
+ return 0;
+}
- return err;
+/*
+ * Make sure 'handle' has at least 'check_cred' credits. If not, restart
+ * transaction with 'restart_cred' credits. The function drops i_data_sem
+ * when restarting transaction and gets it after transaction is restarted.
+ *
+ * The function returns 0 on success, 1 if transaction had to be restarted,
+ * and < 0 in case of fatal error.
+ */
+int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
+ int check_cred, int restart_cred,
+ int revoke_cred)
+{
+ int ret;
+ int dropped = 0;
+
+ ret = ext4_journal_ensure_credits_fn(handle, check_cred, restart_cred,
+ revoke_cred, ext4_ext_trunc_restart_fn(inode, &dropped));
+ if (dropped)
+ down_write(&EXT4_I(inode)->i_data_sem);
+ return ret;
}
/*
@@ -1753,16 +1765,9 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
*/
if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN)
return 0;
- /*
- * The check for IO to unwritten extent is somewhat racy as we
- * increment i_unwritten / set EXT4_STATE_DIO_UNWRITTEN only after
- * dropping i_data_sem. But reserved blocks should save us in that
- * case.
- */
+
if (ext4_ext_is_unwritten(ex1) &&
- (ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN) ||
- atomic_read(&EXT4_I(inode)->i_unwritten) ||
- (ext1_ee_len + ext2_ee_len > EXT_UNWRITTEN_MAX_LEN)))
+ ext1_ee_len + ext2_ee_len > EXT_UNWRITTEN_MAX_LEN)
return 0;
#ifdef AGGRESSIVE_TEST
if (ext1_ee_len >= 4)
@@ -1840,7 +1845,8 @@ static void ext4_ext_try_to_merge_up(handle_t *handle,
* group descriptor to release the extent tree block. If we
* can't get the journal credits, give up.
*/
- if (ext4_journal_extend(handle, 2))
+ if (ext4_journal_extend(handle, 2,
+ ext4_free_metadata_revoke_credits(inode->i_sb, 1)))
return;
/*
@@ -2727,7 +2733,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
int err = 0, correct_index = 0;
- int depth = ext_depth(inode), credits;
+ int depth = ext_depth(inode), credits, revoke_credits;
struct ext4_extent_header *eh;
ext4_lblk_t a, b;
unsigned num;
@@ -2819,10 +2825,23 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
credits += (ext_depth(inode)) + 1;
}
credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
-
- err = ext4_ext_truncate_extend_restart(handle, inode, credits);
- if (err)
+ /*
+ * We may end up freeing some index blocks and data from the
+ * punched range. Note that partial clusters are accounted for
+ * by ext4_free_data_revoke_credits().
+ */
+ revoke_credits =
+ ext4_free_metadata_revoke_credits(inode->i_sb,
+ ext_depth(inode)) +
+ ext4_free_data_revoke_credits(inode, b - a + 1);
+
+ err = ext4_datasem_ensure_credits(handle, inode, credits,
+ credits, revoke_credits);
+ if (err) {
+ if (err > 0)
+ err = -EAGAIN;
goto out;
+ }
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
@@ -2948,7 +2967,9 @@ int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
ext_debug("truncate since %u to %u\n", start, end);
/* probably first extent we're gonna free will be last in block */
- handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, depth + 1);
+ handle = ext4_journal_start_with_revoke(inode, EXT4_HT_TRUNCATE,
+ depth + 1,
+ ext4_free_metadata_revoke_credits(inode->i_sb, depth));
if (IS_ERR(handle))
return PTR_ERR(handle);
@@ -4962,23 +4983,13 @@ int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
int ret = 0;
int ret2 = 0;
struct ext4_map_blocks map;
- unsigned int credits, blkbits = inode->i_blkbits;
+ unsigned int blkbits = inode->i_blkbits;
+ unsigned int credits = 0;
map.m_lblk = offset >> blkbits;
max_blocks = EXT4_MAX_BLOCKS(len, offset, blkbits);
- /*
- * This is somewhat ugly but the idea is clear: When transaction is
- * reserved, everything goes into it. Otherwise we rather start several
- * smaller transactions for conversion of each extent separately.
- */
- if (handle) {
- handle = ext4_journal_start_reserved(handle,
- EXT4_HT_EXT_CONVERT);
- if (IS_ERR(handle))
- return PTR_ERR(handle);
- credits = 0;
- } else {
+ if (!handle) {
/*
* credits to insert 1 extent into extent tree
*/
@@ -5009,11 +5020,40 @@ int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
if (ret <= 0 || ret2)
break;
}
- if (!credits)
- ret2 = ext4_journal_stop(handle);
return ret > 0 ? ret2 : ret;
}
+int ext4_convert_unwritten_io_end_vec(handle_t *handle, ext4_io_end_t *io_end)
+{
+ int ret, err = 0;
+ struct ext4_io_end_vec *io_end_vec;
+
+ /*
+ * This is somewhat ugly but the idea is clear: When transaction is
+ * reserved, everything goes into it. Otherwise we rather start several
+ * smaller transactions for conversion of each extent separately.
+ */
+ if (handle) {
+ handle = ext4_journal_start_reserved(handle,
+ EXT4_HT_EXT_CONVERT);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ }
+
+ list_for_each_entry(io_end_vec, &io_end->list_vec, list) {
+ ret = ext4_convert_unwritten_extents(handle, io_end->inode,
+ io_end_vec->offset,
+ io_end_vec->size);
+ if (ret)
+ break;
+ }
+
+ if (handle)
+ err = ext4_journal_stop(handle);
+
+ return ret < 0 ? ret : err;
+}
+
/*
* If newes is not existing extent (newes->ec_pblk equals zero) find
* delayed extent at start of newes and update newes accordingly and
@@ -5206,13 +5246,10 @@ ext4_access_path(handle_t *handle, struct inode *inode,
* descriptor) for each block group; assume two block
* groups
*/
- if (handle->h_buffer_credits < 7) {
- credits = ext4_writepage_trans_blocks(inode);
- err = ext4_ext_truncate_extend_restart(handle, inode, credits);
- /* EAGAIN is success */
- if (err && err != -EAGAIN)
- return err;
- }
+ credits = ext4_writepage_trans_blocks(inode);
+ err = ext4_datasem_ensure_credits(handle, inode, 7, credits, 0);
+ if (err < 0)
+ return err;
err = ext4_ext_get_access(handle, inode, path);
return err;