Commit 72382264 authored by Andreas Gruenbacher's avatar Andreas Gruenbacher
Browse files

gfs2: Pull return value test out of should_fault_in_pages 



Pull the return value test of the previous read or write operation out
of should_fault_in_pages().  In a following patch, we'll fault in pages
before the I/O and there will be no return value to check.

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
parent 6d22ff47

fs/gfs2/file.c

+22 −12
Original line number Diff line number Diff line
@@ -770,7 +770,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end, 
	return ret ? ret : ret1;

}



static inline bool should_fault_in_pages(ssize_t ret, struct iov_iter *i,

static inline bool should_fault_in_pages(struct iov_iter *i,

					 size_t *prev_count,

					 size_t *window_size)

{
@@ -779,8 +779,6 @@ static inline bool should_fault_in_pages(ssize_t ret, struct iov_iter *i, 


	if (likely(!count))

		return false;

	if (ret <= 0 && ret != -EFAULT)

		return false;

	if (!iter_is_iovec(i))

		return false;
@@ -842,10 +840,12 @@ static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to, 
			   IOMAP_DIO_PARTIAL, read);

	to->nofault = false;

	pagefault_enable();

	if (ret <= 0 && ret != -EFAULT)

		goto out_unlock;

	if (ret > 0)

		read = ret;



	if (should_fault_in_pages(ret, to, &prev_count, &window_size)) {

	if (should_fault_in_pages(to, &prev_count, &window_size)) {

		gfs2_holder_allow_demote(gh);

		window_size -= fault_in_iov_iter_writeable(to, window_size);

		gfs2_holder_disallow_demote(gh);
@@ -855,6 +855,7 @@ static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to, 
			goto retry;

		}

	}

out_unlock:

	if (gfs2_holder_queued(gh))

		gfs2_glock_dq(gh);

out_uninit:
@@ -899,20 +900,23 @@ static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from, 
		goto out_uninit;

	/* Silently fall back to buffered I/O when writing beyond EOF */

	if (iocb->ki_pos + iov_iter_count(from) > i_size_read(&ip->i_inode))

		goto out;

		goto out_unlock;

retry_under_glock:



	from->nofault = true;

	ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL,

			   IOMAP_DIO_PARTIAL, written);

	from->nofault = false;



	if (ret <= 0) {

		if (ret == -ENOTBLK)

			ret = 0;

		if (ret != -EFAULT)

			goto out_unlock;

	}

	if (ret > 0)

		written = ret;



	if (should_fault_in_pages(ret, from, &prev_count, &window_size)) {

	if (should_fault_in_pages(from, &prev_count, &window_size)) {

		gfs2_holder_allow_demote(gh);

		window_size -= fault_in_iov_iter_readable(from, window_size);

		gfs2_holder_disallow_demote(gh);
@@ -922,7 +926,7 @@ static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from, 
			goto retry;

		}

	}

out:

out_unlock:

	if (gfs2_holder_queued(gh))

		gfs2_glock_dq(gh);

out_uninit:
@@ -975,10 +979,12 @@ static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 
	pagefault_disable();

	ret = generic_file_read_iter(iocb, to);

	pagefault_enable();

	if (ret <= 0 && ret != -EFAULT)

		goto out_unlock;

	if (ret > 0)

		read += ret;



	if (should_fault_in_pages(ret, to, &prev_count, &window_size)) {

	if (should_fault_in_pages(to, &prev_count, &window_size)) {

		gfs2_holder_allow_demote(&gh);

		window_size -= fault_in_iov_iter_writeable(to, window_size);

		gfs2_holder_disallow_demote(&gh);
@@ -988,6 +994,7 @@ static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 
			goto retry;

		}

	}

out_unlock:

	if (gfs2_holder_queued(&gh))

		gfs2_glock_dq(&gh);

out_uninit:
@@ -1050,8 +1057,11 @@ static ssize_t gfs2_file_buffered_write(struct kiocb *iocb, 
	if (inode == sdp->sd_rindex)

		gfs2_glock_dq_uninit(statfs_gh);



	if (ret <= 0 && ret != -EFAULT)

		goto out_unlock;



	from->count = orig_count - written;

	if (should_fault_in_pages(ret, from, &prev_count, &window_size)) {

	if (should_fault_in_pages(from, &prev_count, &window_size)) {

		gfs2_holder_allow_demote(gh);

		window_size -= fault_in_iov_iter_readable(from, window_size);

		gfs2_holder_disallow_demote(gh);