Commit dc41aeed authored by Russell Cattelan's avatar Russell Cattelan Committed by Steven Whitehouse
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[GFS2] Fix for mmap() bug in readpage 



Fix for Red Hat bz 205307. Don't need to lock in readpage if
the higher level code has already grabbed the lock.

Signed-off-by: default avatarRussell Cattelan <cattelan@redhat.com>
Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
parent 7a6bbacb

fs/gfs2/ops_address.c

+5 −2
Original line number Diff line number Diff line
@@ -218,14 +218,16 @@ static int gfs2_readpage(struct file *file, struct page *page) 
{

	struct gfs2_inode *ip = GFS2_I(page->mapping->host);

	struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);

	struct gfs2_file *gf = NULL;

	struct gfs2_holder gh;

	int error;

	int do_unlock = 0;



	if (likely(file != &gfs2_internal_file_sentinel)) {

		if (file) {

			struct gfs2_file *gf = file->private_data;

			gf = file->private_data;

			if (test_bit(GFF_EXLOCK, &gf->f_flags))

				/* gfs2_sharewrite_nopage has grabbed the ip->i_gl already */

				goto skip_lock;

		}

		gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|GL_AOP, &gh);
@@ -245,7 +247,8 @@ static int gfs2_readpage(struct file *file, struct page *page) 
	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))

		error = -EIO;



	if (file != &gfs2_internal_file_sentinel) {

	if (gf && !test_bit(GFF_EXLOCK, &gf->f_flags) &&

	    file != &gfs2_internal_file_sentinel) {

		gfs2_glock_dq_m(1, &gh);

		gfs2_holder_uninit(&gh);

	}