#include <linux/pagevec.h>
#include <linux/uio.h>
#include <linux/mman.h>
+#include <linux/backing-dev.h>
#include "ext4.h"
#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
+#include "truncate.h"
+
+static bool ext4_dio_supported(struct inode *inode)
+{
+ if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode))
+ return false;
+ if (fsverity_active(inode))
+ return false;
+ if (ext4_should_journal_data(inode))
+ return false;
+ if (ext4_has_inline_data(inode))
+ return false;
+ return true;
+}
+
+static ssize_t ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ ssize_t ret;
+ struct inode *inode = file_inode(iocb->ki_filp);
+
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (!inode_trylock_shared(inode))
+ return -EAGAIN;
+ } else {
+ inode_lock_shared(inode);
+ }
+
+ if (!ext4_dio_supported(inode)) {
+ inode_unlock_shared(inode);
+ /*
+ * Fallback to buffered I/O if the operation being performed on
+ * the inode is not supported by direct I/O. The IOCB_DIRECT
+ * flag needs to be cleared here in order to ensure that the
+ * direct I/O path within generic_file_read_iter() is not
+ * taken.
+ */
+ iocb->ki_flags &= ~IOCB_DIRECT;
+ return generic_file_read_iter(iocb, to);
+ }
+
+ ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL,
+ is_sync_kiocb(iocb));
+ inode_unlock_shared(inode);
+
+ file_accessed(iocb->ki_filp);
+ return ret;
+}
#ifdef CONFIG_FS_DAX
static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
- if (unlikely(ext4_forced_shutdown(EXT4_SB(file_inode(iocb->ki_filp)->i_sb))))
+ struct inode *inode = file_inode(iocb->ki_filp);
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
return -EIO;
if (!iov_iter_count(to))
return 0; /* skip atime */
#ifdef CONFIG_FS_DAX
- if (IS_DAX(file_inode(iocb->ki_filp)))
+ if (IS_DAX(inode))
return ext4_dax_read_iter(iocb, to);
#endif
+ if (iocb->ki_flags & IOCB_DIRECT)
+ return ext4_dio_read_iter(iocb, to);
+
return generic_file_read_iter(iocb, to);
}
return 0;
}
-static void ext4_unwritten_wait(struct inode *inode)
-{
- wait_queue_head_t *wq = ext4_ioend_wq(inode);
-
- wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_unwritten) == 0));
-}
-
/*
* This tests whether the IO in question is block-aligned or not.
* Ext4 utilizes unwritten extents when hole-filling during direct IO, and they
struct inode *inode = file_inode(iocb->ki_filp);
ssize_t ret;
+ if (unlikely(IS_IMMUTABLE(inode)))
+ return -EPERM;
+
ret = generic_write_checks(iocb, from);
if (ret <= 0)
return ret;
- if (unlikely(IS_IMMUTABLE(inode)))
- return -EPERM;
-
/*
* If we have encountered a bitmap-format file, the size limit
* is smaller than s_maxbytes, which is for extent-mapped files.
return -EFBIG;
iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos);
}
+
+ ret = file_modified(iocb->ki_filp);
+ if (ret)
+ return ret;
+
return iov_iter_count(from);
}
-#ifdef CONFIG_FS_DAX
-static ssize_t
-ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
+static ssize_t ext4_buffered_write_iter(struct kiocb *iocb,
+ struct iov_iter *from)
{
- struct inode *inode = file_inode(iocb->ki_filp);
ssize_t ret;
+ struct inode *inode = file_inode(iocb->ki_filp);
- if (!inode_trylock(inode)) {
- if (iocb->ki_flags & IOCB_NOWAIT)
- return -EAGAIN;
- inode_lock(inode);
- }
+ if (iocb->ki_flags & IOCB_NOWAIT)
+ return -EOPNOTSUPP;
+
+ inode_lock(inode);
ret = ext4_write_checks(iocb, from);
if (ret <= 0)
goto out;
- ret = file_remove_privs(iocb->ki_filp);
- if (ret)
- goto out;
- ret = file_update_time(iocb->ki_filp);
- if (ret)
- goto out;
- ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops);
+ current->backing_dev_info = inode_to_bdi(inode);
+ ret = generic_perform_write(iocb->ki_filp, from, iocb->ki_pos);
+ current->backing_dev_info = NULL;
+
out:
inode_unlock(inode);
- if (ret > 0)
+ if (likely(ret > 0)) {
+ iocb->ki_pos += ret;
ret = generic_write_sync(iocb, ret);
+ }
+
return ret;
}
-#endif
-static ssize_t
-ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset,
+ ssize_t written, size_t count)
{
+ handle_t *handle;
+ bool truncate = false;
+ u8 blkbits = inode->i_blkbits;
+ ext4_lblk_t written_blk, end_blk;
+
+ /*
+ * Note that EXT4_I(inode)->i_disksize can get extended up to
+ * inode->i_size while the I/O was running due to writeback of delalloc
+ * blocks. But, the code in ext4_iomap_alloc() is careful to use
+ * zeroed/unwritten extents if this is possible; thus we won't leave
+ * uninitialized blocks in a file even if we didn't succeed in writing
+ * as much as we intended.
+ */
+ WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize);
+ if (offset + count <= EXT4_I(inode)->i_disksize) {
+ /*
+ * We need to ensure that the inode is removed from the orphan
+ * list if it has been added prematurely, due to writeback of
+ * delalloc blocks.
+ */
+ if (!list_empty(&EXT4_I(inode)->i_orphan) && inode->i_nlink) {
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
+
+ if (IS_ERR(handle)) {
+ ext4_orphan_del(NULL, inode);
+ return PTR_ERR(handle);
+ }
+
+ ext4_orphan_del(handle, inode);
+ ext4_journal_stop(handle);
+ }
+
+ return written;
+ }
+
+ if (written < 0)
+ goto truncate;
+
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
+ if (IS_ERR(handle)) {
+ written = PTR_ERR(handle);
+ goto truncate;
+ }
+
+ if (ext4_update_inode_size(inode, offset + written))
+ ext4_mark_inode_dirty(handle, inode);
+
+ /*
+ * We may need to truncate allocated but not written blocks beyond EOF.
+ */
+ written_blk = ALIGN(offset + written, 1 << blkbits);
+ end_blk = ALIGN(offset + count, 1 << blkbits);
+ if (written_blk < end_blk && ext4_can_truncate(inode))
+ truncate = true;
+
+ /*
+ * Remove the inode from the orphan list if it has been extended and
+ * everything went OK.
+ */
+ if (!truncate && inode->i_nlink)
+ ext4_orphan_del(handle, inode);
+ ext4_journal_stop(handle);
+
+ if (truncate) {
+truncate:
+ ext4_truncate_failed_write(inode);
+ /*
+ * If the truncate operation failed early, then the inode may
+ * still be on the orphan list. In that case, we need to try
+ * remove the inode from the in-memory linked list.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+ }
+
+ return written;
+}
+
+static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size,
+ int error, unsigned int flags)
+{
+ loff_t offset = iocb->ki_pos;
struct inode *inode = file_inode(iocb->ki_filp);
- int o_direct = iocb->ki_flags & IOCB_DIRECT;
- int unaligned_aio = 0;
- int overwrite = 0;
+
+ if (error)
+ return error;
+
+ if (size && flags & IOMAP_DIO_UNWRITTEN)
+ return ext4_convert_unwritten_extents(NULL, inode,
+ offset, size);
+
+ return 0;
+}
+
+static const struct iomap_dio_ops ext4_dio_write_ops = {
+ .end_io = ext4_dio_write_end_io,
+};
+
+static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
ssize_t ret;
+ size_t count;
+ loff_t offset;
+ handle_t *handle;
+ struct inode *inode = file_inode(iocb->ki_filp);
+ bool extend = false, overwrite = false, unaligned_aio = false;
- if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
- return -EIO;
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (!inode_trylock(inode))
+ return -EAGAIN;
+ } else {
+ inode_lock(inode);
+ }
+
+ if (!ext4_dio_supported(inode)) {
+ inode_unlock(inode);
+ /*
+ * Fallback to buffered I/O if the inode does not support
+ * direct I/O.
+ */
+ return ext4_buffered_write_iter(iocb, from);
+ }
+
+ ret = ext4_write_checks(iocb, from);
+ if (ret <= 0) {
+ inode_unlock(inode);
+ return ret;
+ }
+
+ /*
+ * Unaligned asynchronous direct I/O must be serialized among each
+ * other as the zeroing of partial blocks of two competing unaligned
+ * asynchronous direct I/O writes can result in data corruption.
+ */
+ offset = iocb->ki_pos;
+ count = iov_iter_count(from);
+ if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
+ !is_sync_kiocb(iocb) && ext4_unaligned_aio(inode, from, offset)) {
+ unaligned_aio = true;
+ inode_dio_wait(inode);
+ }
+
+ /*
+ * Determine whether the I/O will overwrite allocated and initialized
+ * blocks. If so, check to see whether it is possible to take the
+ * dioread_nolock path.
+ */
+ if (!unaligned_aio && ext4_overwrite_io(inode, offset, count) &&
+ ext4_should_dioread_nolock(inode)) {
+ overwrite = true;
+ downgrade_write(&inode->i_rwsem);
+ }
+
+ if (offset + count > EXT4_I(inode)->i_disksize) {
+ 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;
+ }
+
+ extend = true;
+ ext4_journal_stop(handle);
+ }
+
+ ret = iomap_dio_rw(iocb, from, &ext4_iomap_ops, &ext4_dio_write_ops,
+ is_sync_kiocb(iocb) || unaligned_aio || extend);
+
+ if (extend)
+ ret = ext4_handle_inode_extension(inode, offset, ret, count);
+
+out:
+ if (overwrite)
+ inode_unlock_shared(inode);
+ else
+ inode_unlock(inode);
+
+ if (ret >= 0 && iov_iter_count(from)) {
+ ssize_t err;
+ loff_t endbyte;
+
+ offset = iocb->ki_pos;
+ err = ext4_buffered_write_iter(iocb, from);
+ if (err < 0)
+ return err;
+
+ /*
+ * We need to ensure that the pages within the page cache for
+ * the range covered by this I/O are written to disk and
+ * invalidated. This is in attempt to preserve the expected
+ * direct I/O semantics in the case we fallback to buffered I/O
+ * to complete off the I/O request.
+ */
+ ret += err;
+ endbyte = offset + err - 1;
+ err = filemap_write_and_wait_range(iocb->ki_filp->f_mapping,
+ offset, endbyte);
+ if (!err)
+ invalidate_mapping_pages(iocb->ki_filp->f_mapping,
+ offset >> PAGE_SHIFT,
+ endbyte >> PAGE_SHIFT);
+ }
+
+ return ret;
+}
#ifdef CONFIG_FS_DAX
- if (IS_DAX(inode))
- return ext4_dax_write_iter(iocb, from);
-#endif
+static ssize_t
+ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ ssize_t ret;
+ size_t count;
+ loff_t offset;
+ handle_t *handle;
+ bool extend = false;
+ struct inode *inode = file_inode(iocb->ki_filp);
if (!inode_trylock(inode)) {
if (iocb->ki_flags & IOCB_NOWAIT)
if (ret <= 0)
goto out;
- /*
- * Unaligned direct AIO must be serialized among each other as zeroing
- * of partial blocks of two competing unaligned AIOs can result in data
- * corruption.
- */
- if (o_direct && ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
- !is_sync_kiocb(iocb) &&
- ext4_unaligned_aio(inode, from, iocb->ki_pos)) {
- unaligned_aio = 1;
- ext4_unwritten_wait(inode);
- }
+ offset = iocb->ki_pos;
+ count = iov_iter_count(from);
- iocb->private = &overwrite;
- /* Check whether we do a DIO overwrite or not */
- if (o_direct && !unaligned_aio) {
- if (ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from))) {
- if (ext4_should_dioread_nolock(inode))
- overwrite = 1;
- } else if (iocb->ki_flags & IOCB_NOWAIT) {
- ret = -EAGAIN;
+ if (offset + count > EXT4_I(inode)->i_disksize) {
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
goto out;
}
- }
- ret = __generic_file_write_iter(iocb, from);
- /*
- * Unaligned direct AIO must be the only IO in flight. Otherwise
- * overlapping aligned IO after unaligned might result in data
- * corruption.
- */
- if (ret == -EIOCBQUEUED && unaligned_aio)
- ext4_unwritten_wait(inode);
- inode_unlock(inode);
+ ret = ext4_orphan_add(handle, inode);
+ if (ret) {
+ ext4_journal_stop(handle);
+ goto out;
+ }
- if (ret > 0)
- ret = generic_write_sync(iocb, ret);
+ extend = true;
+ ext4_journal_stop(handle);
+ }
- return ret;
+ ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops);
+ if (extend)
+ ret = ext4_handle_inode_extension(inode, offset, ret, count);
out:
inode_unlock(inode);
+ if (ret > 0)
+ ret = generic_write_sync(iocb, ret);
return ret;
}
+#endif
+
+static ssize_t
+ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct inode *inode = file_inode(iocb->ki_filp);
+
+ if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
+ return -EIO;
+
+#ifdef CONFIG_FS_DAX
+ if (IS_DAX(inode))
+ return ext4_dax_write_iter(iocb, from);
+#endif
+ if (iocb->ki_flags & IOCB_DIRECT)
+ return ext4_dio_write_iter(iocb, from);
+
+ return ext4_buffered_write_iter(iocb, from);
+}
#ifdef CONFIG_FS_DAX
static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf,
maxbytes, i_size_read(inode));
case SEEK_HOLE:
inode_lock_shared(inode);
- offset = iomap_seek_hole(inode, offset, &ext4_iomap_ops);
+ offset = iomap_seek_hole(inode, offset,
+ &ext4_iomap_report_ops);
inode_unlock_shared(inode);
break;
case SEEK_DATA:
inode_lock_shared(inode);
- offset = iomap_seek_data(inode, offset, &ext4_iomap_ops);
+ offset = iomap_seek_data(inode, offset,
+ &ext4_iomap_report_ops);
inode_unlock_shared(inode);
break;
}
projects / linux.git / blobdiff