return err;
}
-/*
- * O_DIRECT for ext3 (or indirect map) based files
- *
- * If the O_DIRECT write will extend the file then add this inode to the
- * orphan list. So recovery will truncate it back to the original size
- * if the machine crashes during the write.
- *
- * If the O_DIRECT write is intantiating holes inside i_size and the machine
- * crashes then stale disk data _may_ be exposed inside the file. But current
- * VFS code falls back into buffered path in that case so we are safe.
- */
-ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
- loff_t offset)
-{
- struct file *file = iocb->ki_filp;
- struct inode *inode = file->f_mapping->host;
- struct ext4_inode_info *ei = EXT4_I(inode);
- handle_t *handle;
- ssize_t ret;
- int orphan = 0;
- size_t count = iov_iter_count(iter);
- int retries = 0;
-
- if (iov_iter_rw(iter) == WRITE) {
- loff_t final_size = offset + count;
-
- 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);
- }
- }
-
-retry:
- if (iov_iter_rw(iter) == READ && 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);
- goto locked;
- }
- if (IS_DAX(inode))
- ret = dax_do_io(iocb, inode, iter, offset,
- ext4_dio_get_block, NULL, 0);
- else
- ret = __blockdev_direct_IO(iocb, inode,
- inode->i_sb->s_bdev, iter,
- offset, ext4_dio_get_block,
- NULL, NULL, 0);
- inode_dio_end(inode);
- } else {
-locked:
- if (IS_DAX(inode))
- ret = dax_do_io(iocb, inode, iter, offset,
- ext4_dio_get_block, NULL, DIO_LOCKING);
- else
- ret = blockdev_direct_IO(iocb, inode, iter, offset,
- ext4_dio_get_block);
-
- if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
- loff_t isize = i_size_read(inode);
- loff_t end = offset + count;
-
- if (end > isize)
- ext4_truncate_failed_write(inode);
- }
- }
- if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
- goto retry;
-
- 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;
-}
-
/*
* Calculate the number of metadata blocks need to reserve
* to allocate a new block at @lblocks for non extent file based file
}
/*
- * 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.
*
* if the machine crashes during the write.
*
*/
-static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
- loff_t offset)
+static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter,
+ loff_t offset)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
+ struct ext4_inode_info *ei = EXT4_I(inode);
ssize_t ret;
size_t count = iov_iter_count(iter);
int overwrite = 0;
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, offset);
+ 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);
* 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);
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
iocb->private = NULL;
if (overwrite)
get_block_func = ext4_dio_get_block_overwrite;
- else if (is_sync_kiocb(iocb)) {
+ 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 {
#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)) {
+ dio_flags &= ~DIO_SKIP_HOLES;
ret = dax_do_io(iocb, inode, iter, offset, get_block_func,
ext4_end_io_dio, dio_flags);
- else
+ } else
ret = __blockdev_direct_IO(iocb, inode,
inode->i_sb->s_bdev, iter, offset,
get_block_func,
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,
+ loff_t offset)
+{
+ 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, offset, ext4_dio_get_block,
+ NULL, unlocked ? 0 : DIO_LOCKING);
+ } else {
+ ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev,
+ iter, offset, ext4_dio_get_block,
+ NULL, NULL,
+ unlocked ? 0 : DIO_LOCKING);
+ }
+ if (unlocked)
+ inode_dio_end(inode);
return ret;
}
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, offset);
+ if (iov_iter_rw(iter) == READ)
+ ret = ext4_direct_IO_read(iocb, iter, offset);
else
- ret = ext4_ind_direct_IO(iocb, iter, offset);
+ ret = ext4_direct_IO_write(iocb, iter, offset);
trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret);
return ret;
}
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff