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Diffstat (limited to 'fs/ext4/extents.c')
-rw-r--r--fs/ext4/extents.c303
1 files changed, 157 insertions, 146 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 551353b1b17a..95bf4679ac54 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -15,7 +15,7 @@
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
- * You should have received a copy of the GNU General Public Licens
+ * You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
@@ -1736,6 +1736,12 @@ 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) ||
@@ -2293,59 +2299,69 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
}
/*
- * ext4_ext_put_gap_in_cache:
- * calculate boundaries of the gap that the requested block fits into
- * and cache this gap
+ * ext4_ext_determine_hole - determine hole around given block
+ * @inode: inode we lookup in
+ * @path: path in extent tree to @lblk
+ * @lblk: pointer to logical block around which we want to determine hole
+ *
+ * Determine hole length (and start if easily possible) around given logical
+ * block. We don't try too hard to find the beginning of the hole but @path
+ * actually points to extent before @lblk, we provide it.
+ *
+ * The function returns the length of a hole starting at @lblk. We update @lblk
+ * to the beginning of the hole if we managed to find it.
*/
-static void
-ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
- ext4_lblk_t block)
+static ext4_lblk_t ext4_ext_determine_hole(struct inode *inode,
+ struct ext4_ext_path *path,
+ ext4_lblk_t *lblk)
{
int depth = ext_depth(inode);
- ext4_lblk_t len;
- ext4_lblk_t lblock;
struct ext4_extent *ex;
- struct extent_status es;
+ ext4_lblk_t len;
ex = path[depth].p_ext;
if (ex == NULL) {
/* there is no extent yet, so gap is [0;-] */
- lblock = 0;
+ *lblk = 0;
len = EXT_MAX_BLOCKS;
- ext_debug("cache gap(whole file):");
- } else if (block < le32_to_cpu(ex->ee_block)) {
- lblock = block;
- len = le32_to_cpu(ex->ee_block) - block;
- ext_debug("cache gap(before): %u [%u:%u]",
- block,
- le32_to_cpu(ex->ee_block),
- ext4_ext_get_actual_len(ex));
- } else if (block >= le32_to_cpu(ex->ee_block)
+ } else if (*lblk < le32_to_cpu(ex->ee_block)) {
+ len = le32_to_cpu(ex->ee_block) - *lblk;
+ } else if (*lblk >= le32_to_cpu(ex->ee_block)
+ ext4_ext_get_actual_len(ex)) {
ext4_lblk_t next;
- lblock = le32_to_cpu(ex->ee_block)
- + ext4_ext_get_actual_len(ex);
+ *lblk = le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex);
next = ext4_ext_next_allocated_block(path);
- ext_debug("cache gap(after): [%u:%u] %u",
- le32_to_cpu(ex->ee_block),
- ext4_ext_get_actual_len(ex),
- block);
- BUG_ON(next == lblock);
- len = next - lblock;
+ BUG_ON(next == *lblk);
+ len = next - *lblk;
} else {
BUG();
}
+ return len;
+}
+
+/*
+ * ext4_ext_put_gap_in_cache:
+ * calculate boundaries of the gap that the requested block fits into
+ * and cache this gap
+ */
+static void
+ext4_ext_put_gap_in_cache(struct inode *inode, ext4_lblk_t hole_start,
+ ext4_lblk_t hole_len)
+{
+ struct extent_status es;
- ext4_es_find_delayed_extent_range(inode, lblock, lblock + len - 1, &es);
+ ext4_es_find_delayed_extent_range(inode, hole_start,
+ hole_start + hole_len - 1, &es);
if (es.es_len) {
/* There's delayed extent containing lblock? */
- if (es.es_lblk <= lblock)
+ if (es.es_lblk <= hole_start)
return;
- len = min(es.es_lblk - lblock, len);
+ hole_len = min(es.es_lblk - hole_start, hole_len);
}
- ext_debug(" -> %u:%u\n", lblock, len);
- ext4_es_insert_extent(inode, lblock, len, ~0, EXTENT_STATUS_HOLE);
+ ext_debug(" -> %u:%u\n", hole_start, hole_len);
+ ext4_es_insert_extent(inode, hole_start, hole_len, ~0,
+ EXTENT_STATUS_HOLE);
}
/*
@@ -3119,19 +3135,11 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
{
ext4_fsblk_t ee_pblock;
unsigned int ee_len;
- int ret;
ee_len = ext4_ext_get_actual_len(ex);
ee_pblock = ext4_ext_pblock(ex);
-
- if (ext4_encrypted_inode(inode))
- return ext4_encrypted_zeroout(inode, ex);
-
- ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
- if (ret > 0)
- ret = 0;
-
- return ret;
+ return ext4_issue_zeroout(inode, le32_to_cpu(ex->ee_block), ee_pblock,
+ ee_len);
}
/*
@@ -3935,8 +3943,8 @@ get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start,
static int
convert_initialized_extent(handle_t *handle, struct inode *inode,
struct ext4_map_blocks *map,
- struct ext4_ext_path **ppath, int flags,
- unsigned int allocated, ext4_fsblk_t newblock)
+ struct ext4_ext_path **ppath,
+ unsigned int allocated)
{
struct ext4_ext_path *path = *ppath;
struct ext4_extent *ex;
@@ -4015,7 +4023,6 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path = *ppath;
int ret = 0;
int err = 0;
- ext4_io_end_t *io = ext4_inode_aio(inode);
ext_debug("ext4_ext_handle_unwritten_extents: inode %lu, logical "
"block %llu, max_blocks %u, flags %x, allocated %u\n",
@@ -4038,20 +4045,19 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode,
flags | EXT4_GET_BLOCKS_CONVERT);
if (ret <= 0)
goto out;
- /*
- * Flag the inode(non aio case) or end_io struct (aio case)
- * that this IO needs to conversion to written when IO is
- * completed
- */
- if (io)
- ext4_set_io_unwritten_flag(inode, io);
- else
- ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
map->m_flags |= EXT4_MAP_UNWRITTEN;
goto out;
}
/* IO end_io complete, convert the filled extent to written */
if (flags & EXT4_GET_BLOCKS_CONVERT) {
+ if (flags & EXT4_GET_BLOCKS_ZERO) {
+ if (allocated > map->m_len)
+ allocated = map->m_len;
+ err = ext4_issue_zeroout(inode, map->m_lblk, newblock,
+ allocated);
+ if (err < 0)
+ goto out2;
+ }
ret = ext4_convert_unwritten_extents_endio(handle, inode, map,
ppath);
if (ret >= 0) {
@@ -4283,9 +4289,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
unsigned int allocated = 0, offset = 0;
unsigned int allocated_clusters = 0;
struct ext4_allocation_request ar;
- ext4_io_end_t *io = ext4_inode_aio(inode);
ext4_lblk_t cluster_offset;
- int set_unwritten = 0;
bool map_from_cluster = false;
ext_debug("blocks %u/%u requested for inode %lu\n",
@@ -4347,7 +4351,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
(flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) {
allocated = convert_initialized_extent(
handle, inode, map, &path,
- flags, allocated, newblock);
+ allocated);
goto out2;
} else if (!ext4_ext_is_unwritten(ex))
goto out;
@@ -4368,11 +4372,22 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
* we couldn't try to create block if create flag is zero
*/
if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
+ ext4_lblk_t hole_start, hole_len;
+
+ hole_start = map->m_lblk;
+ hole_len = ext4_ext_determine_hole(inode, path, &hole_start);
/*
* put just found gap into cache to speed up
* subsequent requests
*/
- ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
+ ext4_ext_put_gap_in_cache(inode, hole_start, hole_len);
+
+ /* Update hole_len to reflect hole size after map->m_lblk */
+ if (hole_start != map->m_lblk)
+ hole_len -= map->m_lblk - hole_start;
+ map->m_pblk = 0;
+ map->m_len = min_t(unsigned int, map->m_len, hole_len);
+
goto out2;
}
@@ -4482,15 +4497,6 @@ got_allocated_blocks:
if (flags & EXT4_GET_BLOCKS_UNWRIT_EXT){
ext4_ext_mark_unwritten(&newex);
map->m_flags |= EXT4_MAP_UNWRITTEN;
- /*
- * io_end structure was created for every IO write to an
- * unwritten extent. To avoid unnecessary conversion,
- * here we flag the IO that really needs the conversion.
- * For non asycn direct IO case, flag the inode state
- * that we need to perform conversion when IO is done.
- */
- if (flags & EXT4_GET_BLOCKS_PRE_IO)
- set_unwritten = 1;
}
err = 0;
@@ -4501,14 +4507,6 @@ got_allocated_blocks:
err = ext4_ext_insert_extent(handle, inode, &path,
&newex, flags);
- if (!err && set_unwritten) {
- if (io)
- ext4_set_io_unwritten_flag(inode, io);
- else
- ext4_set_inode_state(inode,
- EXT4_STATE_DIO_UNWRITTEN);
- }
-
if (err && free_on_err) {
int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ?
EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0;
@@ -4685,10 +4683,6 @@ static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,
if (len <= EXT_UNWRITTEN_MAX_LEN)
flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
- /* Wait all existing dio workers, newcomers will block on i_mutex */
- ext4_inode_block_unlocked_dio(inode);
- inode_dio_wait(inode);
-
/*
* credits to insert 1 extent into extent tree
*/
@@ -4752,8 +4746,6 @@ retry:
goto retry;
}
- ext4_inode_resume_unlocked_dio(inode);
-
return ret > 0 ? ret2 : ret;
}
@@ -4770,7 +4762,6 @@ static long ext4_zero_range(struct file *file, loff_t offset,
int partial_begin, partial_end;
loff_t start, end;
ext4_lblk_t lblk;
- struct address_space *mapping = inode->i_mapping;
unsigned int blkbits = inode->i_blkbits;
trace_ext4_zero_range(inode, offset, len, mode);
@@ -4786,17 +4777,6 @@ static long ext4_zero_range(struct file *file, loff_t offset,
}
/*
- * Write out all dirty pages to avoid race conditions
- * Then release them.
- */
- if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
- ret = filemap_write_and_wait_range(mapping, offset,
- offset + len - 1);
- if (ret)
- return ret;
- }
-
- /*
* Round up offset. This is not fallocate, we neet to zero out
* blocks, so convert interior block aligned part of the range to
* unwritten and possibly manually zero out unaligned parts of the
@@ -4817,7 +4797,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,
else
max_blocks -= lblk;
- mutex_lock(&inode->i_mutex);
+ inode_lock(inode);
/*
* Indirect files do not support unwritten extnets
@@ -4839,6 +4819,10 @@ static long ext4_zero_range(struct file *file, loff_t offset,
if (mode & FALLOC_FL_KEEP_SIZE)
flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
+ /* Wait all existing dio workers, newcomers will block on i_mutex */
+ ext4_inode_block_unlocked_dio(inode);
+ inode_dio_wait(inode);
+
/* Preallocate the range including the unaligned edges */
if (partial_begin || partial_end) {
ret = ext4_alloc_file_blocks(file,
@@ -4847,7 +4831,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,
round_down(offset, 1 << blkbits)) >> blkbits,
new_size, flags, mode);
if (ret)
- goto out_mutex;
+ goto out_dio;
}
@@ -4856,16 +4840,23 @@ static long ext4_zero_range(struct file *file, loff_t offset,
flags |= (EXT4_GET_BLOCKS_CONVERT_UNWRITTEN |
EXT4_EX_NOCACHE);
- /* Now release the pages and zero block aligned part of pages*/
+ /*
+ * Prevent page faults from reinstantiating pages we have
+ * released from page cache.
+ */
+ down_write(&EXT4_I(inode)->i_mmap_sem);
+ ret = ext4_update_disksize_before_punch(inode, offset, len);
+ if (ret) {
+ up_write(&EXT4_I(inode)->i_mmap_sem);
+ goto out_dio;
+ }
+ /* Now release the pages and zero block aligned part of pages */
truncate_pagecache_range(inode, start, end - 1);
inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
- /* Wait all existing dio workers, newcomers will block on i_mutex */
- ext4_inode_block_unlocked_dio(inode);
- inode_dio_wait(inode);
-
ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size,
flags, mode);
+ up_write(&EXT4_I(inode)->i_mmap_sem);
if (ret)
goto out_dio;
}
@@ -4909,7 +4900,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,
out_dio:
ext4_inode_resume_unlocked_dio(inode);
out_mutex:
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
return ret;
}
@@ -4980,7 +4971,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
if (mode & FALLOC_FL_KEEP_SIZE)
flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
- mutex_lock(&inode->i_mutex);
+ inode_lock(inode);
/*
* We only support preallocation for extent-based files only
@@ -4998,8 +4989,13 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
goto out;
}
+ /* Wait all existing dio workers, newcomers will block on i_mutex */
+ ext4_inode_block_unlocked_dio(inode);
+ inode_dio_wait(inode);
+
ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size,
flags, mode);
+ ext4_inode_resume_unlocked_dio(inode);
if (ret)
goto out;
@@ -5008,7 +5004,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
EXT4_I(inode)->i_sync_tid);
}
out:
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
return ret;
}
@@ -5494,21 +5490,7 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
return ret;
}
- /*
- * Need to round down offset to be aligned with page size boundary
- * for page size > block size.
- */
- ioffset = round_down(offset, PAGE_SIZE);
-
- /* Write out all dirty pages */
- ret = filemap_write_and_wait_range(inode->i_mapping, ioffset,
- LLONG_MAX);
- if (ret)
- return ret;
-
- /* Take mutex lock */
- mutex_lock(&inode->i_mutex);
-
+ inode_lock(inode);
/*
* There is no need to overlap collapse range with EOF, in which case
* it is effectively a truncate operation
@@ -5524,17 +5506,43 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
goto out_mutex;
}
- truncate_pagecache(inode, ioffset);
-
/* Wait for existing dio to complete */
ext4_inode_block_unlocked_dio(inode);
inode_dio_wait(inode);
+ /*
+ * Prevent page faults from reinstantiating pages we have released from
+ * page cache.
+ */
+ down_write(&EXT4_I(inode)->i_mmap_sem);
+ /*
+ * Need to round down offset to be aligned with page size boundary
+ * for page size > block size.
+ */
+ ioffset = round_down(offset, PAGE_SIZE);
+ /*
+ * Write tail of the last page before removed range since it will get
+ * removed from the page cache below.
+ */
+ ret = filemap_write_and_wait_range(inode->i_mapping, ioffset, offset);
+ if (ret)
+ goto out_mmap;
+ /*
+ * Write data that will be shifted to preserve them when discarding
+ * page cache below. We are also protected from pages becoming dirty
+ * by i_mmap_sem.
+ */
+ ret = filemap_write_and_wait_range(inode->i_mapping, offset + len,
+ LLONG_MAX);
+ if (ret)
+ goto out_mmap;
+ truncate_pagecache(inode, ioffset);
+
credits = ext4_writepage_trans_blocks(inode);
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
- goto out_dio;
+ goto out_mmap;
}
down_write(&EXT4_I(inode)->i_data_sem);
@@ -5573,10 +5581,11 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
out_stop:
ext4_journal_stop(handle);
-out_dio:
+out_mmap:
+ up_write(&EXT4_I(inode)->i_mmap_sem);
ext4_inode_resume_unlocked_dio(inode);
out_mutex:
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
return ret;
}
@@ -5627,21 +5636,7 @@ int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
return ret;
}
- /*
- * Need to round down to align start offset to page size boundary
- * for page size > block size.
- */
- ioffset = round_down(offset, PAGE_SIZE);
-
- /* Write out all dirty pages */
- ret = filemap_write_and_wait_range(inode->i_mapping, ioffset,
- LLONG_MAX);
- if (ret)
- return ret;
-
- /* Take mutex lock */
- mutex_lock(&inode->i_mutex);
-
+ inode_lock(inode);
/* Currently just for extent based files */
if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
ret = -EOPNOTSUPP;
@@ -5660,17 +5655,32 @@ int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
goto out_mutex;
}
- truncate_pagecache(inode, ioffset);
-
/* Wait for existing dio to complete */
ext4_inode_block_unlocked_dio(inode);
inode_dio_wait(inode);
+ /*
+ * Prevent page faults from reinstantiating pages we have released from
+ * page cache.
+ */
+ down_write(&EXT4_I(inode)->i_mmap_sem);
+ /*
+ * Need to round down to align start offset to page size boundary
+ * for page size > block size.
+ */
+ ioffset = round_down(offset, PAGE_SIZE);
+ /* Write out all dirty pages */
+ ret = filemap_write_and_wait_range(inode->i_mapping, ioffset,
+ LLONG_MAX);
+ if (ret)
+ goto out_mmap;
+ truncate_pagecache(inode, ioffset);
+
credits = ext4_writepage_trans_blocks(inode);
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
- goto out_dio;
+ goto out_mmap;
}
/* Expand file to avoid data loss if there is error while shifting */
@@ -5741,10 +5751,11 @@ int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
out_stop:
ext4_journal_stop(handle);
-out_dio:
+out_mmap:
+ up_write(&EXT4_I(inode)->i_mmap_sem);
ext4_inode_resume_unlocked_dio(inode);
out_mutex:
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
return ret;
}
@@ -5779,8 +5790,8 @@ ext4_swap_extents(handle_t *handle, struct inode *inode1,
BUG_ON(!rwsem_is_locked(&EXT4_I(inode1)->i_data_sem));
BUG_ON(!rwsem_is_locked(&EXT4_I(inode2)->i_data_sem));
- BUG_ON(!mutex_is_locked(&inode1->i_mutex));
- BUG_ON(!mutex_is_locked(&inode2->i_mutex));
+ BUG_ON(!inode_is_locked(inode1));
+ BUG_ON(!inode_is_locked(inode2));
*erp = ext4_es_remove_extent(inode1, lblk1, count);
if (unlikely(*erp))
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.