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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-24 12:55:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-24 12:55:26 -0700
commit0e01df100b6bf22a1de61b66657502a6454153c5 (patch)
treeaae8f9787efc3014696b3e5ae854c1cf9e472bdd /fs/ext4/inode.c
parenta56f489502e28caac56c8a0735549740f0ae0711 (diff)
parent12735f881952c32b31bc4e433768f18489f79ec9 (diff)
downloadop-kernel-dev-0e01df100b6bf22a1de61b66657502a6454153c5.zip
op-kernel-dev-0e01df100b6bf22a1de61b66657502a6454153c5.tar.gz
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o: "Fix a number of bugs, most notably a potential stale data exposure after a crash and a potential BUG_ON crash if a file has the data journalling flag enabled while it has dirty delayed allocation blocks that haven't been written yet. Also fix a potential crash in the new project quota code and a maliciously corrupted file system. In addition, fix some DAX-specific bugs, including when there is a transient ENOSPC situation and races between writes via direct I/O and an mmap'ed segment that could lead to lost I/O. Finally the usual set of miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits) ext4: pre-zero allocated blocks for DAX IO ext4: refactor direct IO code ext4: fix race in transient ENOSPC detection ext4: handle transient ENOSPC properly for DAX dax: call get_blocks() with create == 1 for write faults to unwritten extents ext4: remove unmeetable inconsisteny check from ext4_find_extent() jbd2: remove excess descriptions for handle_s ext4: remove unnecessary bio get/put ext4: silence UBSAN in ext4_mb_init() ext4: address UBSAN warning in mb_find_order_for_block() ext4: fix oops on corrupted filesystem ext4: fix check of dqget() return value in ext4_ioctl_setproject() ext4: clean up error handling when orphan list is corrupted ext4: fix hang when processing corrupted orphaned inode list ext4: remove trailing \n from ext4_warning/ext4_error calls ext4: fix races between changing inode journal mode and ext4_writepages ext4: handle unwritten or delalloc buffers before enabling data journaling ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart() ext4: do not ask jbd2 to write data for delalloc buffers jbd2: add support for avoiding data writes during transaction commits ...
Diffstat (limited to 'fs/ext4/inode.c')
-rw-r--r--fs/ext4/inode.c323
1 files changed, 216 insertions, 107 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 79b298d..f7140ca6 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -684,6 +684,24 @@ out_sem:
ret = check_block_validity(inode, map);
if (ret != 0)
return ret;
+
+ /*
+ * Inodes with freshly allocated blocks where contents will be
+ * visible after transaction commit must be on transaction's
+ * ordered data list.
+ */
+ if (map->m_flags & EXT4_MAP_NEW &&
+ !(map->m_flags & EXT4_MAP_UNWRITTEN) &&
+ !(flags & EXT4_GET_BLOCKS_ZERO) &&
+ !IS_NOQUOTA(inode) &&
+ ext4_should_order_data(inode)) {
+ if (flags & EXT4_GET_BLOCKS_IO_SUBMIT)
+ ret = ext4_jbd2_inode_add_wait(handle, inode);
+ else
+ ret = ext4_jbd2_inode_add_write(handle, inode);
+ if (ret)
+ return ret;
+ }
}
return retval;
}
@@ -1289,15 +1307,6 @@ static int ext4_write_end(struct file *file,
int i_size_changed = 0;
trace_ext4_write_end(inode, pos, len, copied);
- if (ext4_test_inode_state(inode, EXT4_STATE_ORDERED_MODE)) {
- ret = ext4_jbd2_file_inode(handle, inode);
- if (ret) {
- unlock_page(page);
- put_page(page);
- goto errout;
- }
- }
-
if (ext4_has_inline_data(inode)) {
ret = ext4_write_inline_data_end(inode, pos, len,
copied, page);
@@ -2313,7 +2322,8 @@ static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
* the data was copied into the page cache.
*/
get_blocks_flags = EXT4_GET_BLOCKS_CREATE |
- EXT4_GET_BLOCKS_METADATA_NOFAIL;
+ EXT4_GET_BLOCKS_METADATA_NOFAIL |
+ EXT4_GET_BLOCKS_IO_SUBMIT;
dioread_nolock = ext4_should_dioread_nolock(inode);
if (dioread_nolock)
get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
@@ -2602,11 +2612,14 @@ static int ext4_writepages(struct address_space *mapping,
struct blk_plug plug;
bool give_up_on_write = false;
+ percpu_down_read(&sbi->s_journal_flag_rwsem);
trace_ext4_writepages(inode, wbc);
- if (dax_mapping(mapping))
- return dax_writeback_mapping_range(mapping, inode->i_sb->s_bdev,
- wbc);
+ if (dax_mapping(mapping)) {
+ ret = dax_writeback_mapping_range(mapping, inode->i_sb->s_bdev,
+ wbc);
+ goto out_writepages;
+ }
/*
* No pages to write? This is mainly a kludge to avoid starting
@@ -2776,6 +2789,7 @@ retry:
out_writepages:
trace_ext4_writepages_result(inode, wbc, ret,
nr_to_write - wbc->nr_to_write);
+ percpu_up_read(&sbi->s_journal_flag_rwsem);
return ret;
}
@@ -3215,75 +3229,52 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
}
#ifdef CONFIG_FS_DAX
-int ext4_dax_mmap_get_block(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
+/*
+ * Get block function for DAX IO and mmap faults. It takes care of converting
+ * unwritten extents to written ones and initializes new / converted blocks
+ * to zeros.
+ */
+int ext4_dax_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
{
- int ret, err;
- int credits;
- struct ext4_map_blocks map;
- handle_t *handle = NULL;
- int flags = 0;
-
- ext4_debug("ext4_dax_mmap_get_block: inode %lu, create flag %d\n",
- inode->i_ino, create);
- map.m_lblk = iblock;
- map.m_len = bh_result->b_size >> inode->i_blkbits;
- credits = ext4_chunk_trans_blocks(inode, map.m_len);
- if (create) {
- flags |= EXT4_GET_BLOCKS_PRE_IO | EXT4_GET_BLOCKS_CREATE_ZERO;
- handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- return ret;
- }
- }
+ int ret;
- ret = ext4_map_blocks(handle, inode, &map, flags);
- if (create) {
- err = ext4_journal_stop(handle);
- if (ret >= 0 && err < 0)
- ret = err;
- }
- if (ret <= 0)
- goto out;
- if (map.m_flags & EXT4_MAP_UNWRITTEN) {
- int err2;
+ ext4_debug("inode %lu, create flag %d\n", inode->i_ino, create);
+ if (!create)
+ return _ext4_get_block(inode, iblock, bh_result, 0);
- /*
- * We are protected by i_mmap_sem so we know block cannot go
- * away from under us even though we dropped i_data_sem.
- * Convert extent to written and write zeros there.
- *
- * Note: We may get here even when create == 0.
- */
- handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out;
- }
+ ret = ext4_get_block_trans(inode, iblock, bh_result,
+ EXT4_GET_BLOCKS_PRE_IO |
+ EXT4_GET_BLOCKS_CREATE_ZERO);
+ if (ret < 0)
+ return ret;
- err = ext4_map_blocks(handle, inode, &map,
- EXT4_GET_BLOCKS_CONVERT | EXT4_GET_BLOCKS_CREATE_ZERO);
- if (err < 0)
- ret = err;
- err2 = ext4_journal_stop(handle);
- if (err2 < 0 && ret > 0)
- ret = err2;
- }
-out:
- WARN_ON_ONCE(ret == 0 && create);
- if (ret > 0) {
- map_bh(bh_result, inode->i_sb, map.m_pblk);
+ if (buffer_unwritten(bh_result)) {
/*
- * At least for now we have to clear BH_New so that DAX code
- * doesn't attempt to zero blocks again in a racy way.
+ * We are protected by i_mmap_sem or i_mutex so we know block
+ * cannot go away from under us even though we dropped
+ * i_data_sem. Convert extent to written and write zeros there.
*/
- map.m_flags &= ~EXT4_MAP_NEW;
- ext4_update_bh_state(bh_result, map.m_flags);
- bh_result->b_size = map.m_len << inode->i_blkbits;
- ret = 0;
+ ret = ext4_get_block_trans(inode, iblock, bh_result,
+ EXT4_GET_BLOCKS_CONVERT |
+ EXT4_GET_BLOCKS_CREATE_ZERO);
+ if (ret < 0)
+ return ret;
}
- return ret;
+ /*
+ * At least for now we have to clear BH_New so that DAX code
+ * doesn't attempt to zero blocks again in a racy way.
+ */
+ clear_buffer_new(bh_result);
+ return 0;
+}
+#else
+/* Just define empty function, it will never get called. */
+int ext4_dax_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ BUG();
+ return 0;
}
#endif
@@ -3316,7 +3307,9 @@ static int ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
}
/*
- * For ext4 extent files, ext4 will do direct-io write to holes,
+ * Handling of direct IO writes.
+ *
+ * For ext4 extent files, ext4 will do direct-io write even to holes,
* preallocated extents, and those write extend the file, no need to
* fall back to buffered IO.
*
@@ -3334,10 +3327,11 @@ static int ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
* if the machine crashes during the write.
*
*/
-static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
+ struct ext4_inode_info *ei = EXT4_I(inode);
ssize_t ret;
loff_t offset = iocb->ki_pos;
size_t count = iov_iter_count(iter);
@@ -3345,10 +3339,25 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
get_block_t *get_block_func = NULL;
int dio_flags = 0;
loff_t final_size = offset + count;
+ int orphan = 0;
+ handle_t *handle;
- /* Use the old path for reads and writes beyond i_size. */
- if (iov_iter_rw(iter) != WRITE || final_size > inode->i_size)
- return ext4_ind_direct_IO(iocb, iter);
+ if (final_size > inode->i_size) {
+ /* Credits for sb + inode write */
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+ ret = ext4_orphan_add(handle, inode);
+ if (ret) {
+ ext4_journal_stop(handle);
+ goto out;
+ }
+ orphan = 1;
+ ei->i_disksize = inode->i_size;
+ ext4_journal_stop(handle);
+ }
BUG_ON(iocb->private == NULL);
@@ -3357,8 +3366,7 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
* conversion. This also disallows race between truncate() and
* overwrite DIO as i_dio_count needs to be incremented under i_mutex.
*/
- if (iov_iter_rw(iter) == WRITE)
- inode_dio_begin(inode);
+ inode_dio_begin(inode);
/* If we do a overwrite dio, i_mutex locking can be released */
overwrite = *((int *)iocb->private);
@@ -3367,7 +3375,7 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
inode_unlock(inode);
/*
- * We could direct write to holes and fallocate.
+ * For extent mapped files we could direct write to holes and fallocate.
*
* Allocated blocks to fill the hole are marked as unwritten to prevent
* parallel buffered read to expose the stale data before DIO complete
@@ -3389,7 +3397,23 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
iocb->private = NULL;
if (overwrite)
get_block_func = ext4_dio_get_block_overwrite;
- else if (is_sync_kiocb(iocb)) {
+ else if (IS_DAX(inode)) {
+ /*
+ * We can avoid zeroing for aligned DAX writes beyond EOF. Other
+ * writes need zeroing either because they can race with page
+ * faults or because they use partial blocks.
+ */
+ if (round_down(offset, 1<<inode->i_blkbits) >= inode->i_size &&
+ ext4_aligned_io(inode, offset, count))
+ get_block_func = ext4_dio_get_block;
+ else
+ get_block_func = ext4_dax_get_block;
+ dio_flags = DIO_LOCKING;
+ } else if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) ||
+ round_down(offset, 1 << inode->i_blkbits) >= inode->i_size) {
+ get_block_func = ext4_dio_get_block;
+ dio_flags = DIO_LOCKING | DIO_SKIP_HOLES;
+ } else if (is_sync_kiocb(iocb)) {
get_block_func = ext4_dio_get_block_unwritten_sync;
dio_flags = DIO_LOCKING;
} else {
@@ -3399,10 +3423,10 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
#ifdef CONFIG_EXT4_FS_ENCRYPTION
BUG_ON(ext4_encrypted_inode(inode) && S_ISREG(inode->i_mode));
#endif
- if (IS_DAX(inode))
+ if (IS_DAX(inode)) {
ret = dax_do_io(iocb, inode, iter, get_block_func,
ext4_end_io_dio, dio_flags);
- else
+ } else
ret = __blockdev_direct_IO(iocb, inode,
inode->i_sb->s_bdev, iter,
get_block_func,
@@ -3422,12 +3446,86 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
}
- if (iov_iter_rw(iter) == WRITE)
- inode_dio_end(inode);
+ inode_dio_end(inode);
/* take i_mutex locking again if we do a ovewrite dio */
if (overwrite)
inode_lock(inode);
+ if (ret < 0 && final_size > inode->i_size)
+ ext4_truncate_failed_write(inode);
+
+ /* Handle extending of i_size after direct IO write */
+ if (orphan) {
+ int err;
+
+ /* Credits for sb + inode write */
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
+ if (IS_ERR(handle)) {
+ /* This is really bad luck. We've written the data
+ * but cannot extend i_size. Bail out and pretend
+ * the write failed... */
+ ret = PTR_ERR(handle);
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+
+ goto out;
+ }
+ if (inode->i_nlink)
+ ext4_orphan_del(handle, inode);
+ if (ret > 0) {
+ loff_t end = offset + ret;
+ if (end > inode->i_size) {
+ ei->i_disksize = end;
+ i_size_write(inode, end);
+ /*
+ * We're going to return a positive `ret'
+ * here due to non-zero-length I/O, so there's
+ * no way of reporting error returns from
+ * ext4_mark_inode_dirty() to userspace. So
+ * ignore it.
+ */
+ ext4_mark_inode_dirty(handle, inode);
+ }
+ }
+ err = ext4_journal_stop(handle);
+ if (ret == 0)
+ ret = err;
+ }
+out:
+ return ret;
+}
+
+static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter)
+{
+ int unlocked = 0;
+ struct inode *inode = iocb->ki_filp->f_mapping->host;
+ ssize_t ret;
+
+ if (ext4_should_dioread_nolock(inode)) {
+ /*
+ * Nolock dioread optimization may be dynamically disabled
+ * via ext4_inode_block_unlocked_dio(). Check inode's state
+ * while holding extra i_dio_count ref.
+ */
+ inode_dio_begin(inode);
+ smp_mb();
+ if (unlikely(ext4_test_inode_state(inode,
+ EXT4_STATE_DIOREAD_LOCK)))
+ inode_dio_end(inode);
+ else
+ unlocked = 1;
+ }
+ if (IS_DAX(inode)) {
+ ret = dax_do_io(iocb, inode, iter, ext4_dio_get_block,
+ NULL, unlocked ? 0 : DIO_LOCKING);
+ } else {
+ ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev,
+ iter, ext4_dio_get_block,
+ NULL, NULL,
+ unlocked ? 0 : DIO_LOCKING);
+ }
+ if (unlocked)
+ inode_dio_end(inode);
return ret;
}
@@ -3455,10 +3553,10 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
return 0;
trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
- if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
- ret = ext4_ext_direct_IO(iocb, iter);
+ if (iov_iter_rw(iter) == READ)
+ ret = ext4_direct_IO_read(iocb, iter);
else
- ret = ext4_ind_direct_IO(iocb, iter);
+ ret = ext4_direct_IO_write(iocb, iter);
trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret);
return ret;
}
@@ -3534,10 +3632,7 @@ void ext4_set_aops(struct inode *inode)
{
switch (ext4_inode_journal_mode(inode)) {
case EXT4_INODE_ORDERED_DATA_MODE:
- ext4_set_inode_state(inode, EXT4_STATE_ORDERED_MODE);
- break;
case EXT4_INODE_WRITEBACK_DATA_MODE:
- ext4_clear_inode_state(inode, EXT4_STATE_ORDERED_MODE);
break;
case EXT4_INODE_JOURNAL_DATA_MODE:
inode->i_mapping->a_ops = &ext4_journalled_aops;
@@ -3630,8 +3725,8 @@ static int __ext4_block_zero_page_range(handle_t *handle,
} else {
err = 0;
mark_buffer_dirty(bh);
- if (ext4_test_inode_state(inode, EXT4_STATE_ORDERED_MODE))
- err = ext4_jbd2_file_inode(handle, inode);
+ if (ext4_should_order_data(inode))
+ err = ext4_jbd2_inode_add_write(handle, inode);
}
unlock:
@@ -5429,6 +5524,7 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
journal_t *journal;
handle_t *handle;
int err;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
/*
* We have to be very careful here: changing a data block's
@@ -5445,22 +5541,30 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
return 0;
if (is_journal_aborted(journal))
return -EROFS;
- /* We have to allocate physical blocks for delalloc blocks
- * before flushing journal. otherwise delalloc blocks can not
- * be allocated any more. even more truncate on delalloc blocks
- * could trigger BUG by flushing delalloc blocks in journal.
- * There is no delalloc block in non-journal data mode.
- */
- if (val && test_opt(inode->i_sb, DELALLOC)) {
- err = ext4_alloc_da_blocks(inode);
- if (err < 0)
- return err;
- }
/* Wait for all existing dio workers */
ext4_inode_block_unlocked_dio(inode);
inode_dio_wait(inode);
+ /*
+ * Before flushing the journal and switching inode's aops, we have
+ * to flush all dirty data the inode has. There can be outstanding
+ * delayed allocations, there can be unwritten extents created by
+ * fallocate or buffered writes in dioread_nolock mode covered by
+ * dirty data which can be converted only after flushing the dirty
+ * data (and journalled aops don't know how to handle these cases).
+ */
+ if (val) {
+ down_write(&EXT4_I(inode)->i_mmap_sem);
+ err = filemap_write_and_wait(inode->i_mapping);
+ if (err < 0) {
+ up_write(&EXT4_I(inode)->i_mmap_sem);
+ ext4_inode_resume_unlocked_dio(inode);
+ return err;
+ }
+ }
+
+ percpu_down_write(&sbi->s_journal_flag_rwsem);
jbd2_journal_lock_updates(journal);
/*
@@ -5477,6 +5581,7 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
err = jbd2_journal_flush(journal);
if (err < 0) {
jbd2_journal_unlock_updates(journal);
+ percpu_up_write(&sbi->s_journal_flag_rwsem);
ext4_inode_resume_unlocked_dio(inode);
return err;
}
@@ -5485,6 +5590,10 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
ext4_set_aops(inode);
jbd2_journal_unlock_updates(journal);
+ percpu_up_write(&sbi->s_journal_flag_rwsem);
+
+ if (val)
+ up_write(&EXT4_I(inode)->i_mmap_sem);
ext4_inode_resume_unlocked_dio(inode);
/* Finally we can mark the inode as dirty. */
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