Merge: gfs2: Add proper lockspace locking

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/7391

JIRA: https://issues.redhat.com/browse/RHEL-116886

GFS2 has been calling functions like dlm_lock() even after the lockspace
that these functions operate on has been released with
dlm_release_lockspace().  It has always assumed that those functions
would return -EINVAL in that case, but that was never guaranteed, and it
certainly is no longer the case since commit 4db41bf ("dlm: remove
ls_local_handle from struct dlm_ls").

To fix that, add proper lockspace locking.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Approved-by: Andrew Price <anprice@redhat.com>
Approved-by: Paul Evans <pevans@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>
Approved-by: Abhi Das <adas@redhat.com>

Merged-by: CKI GitLab Kmaint Pipeline Bot <26919896-cki-kmaint-pipeline-bot@users.noreply.gitlab.com>

Author: CKI KWF Bot

fs/gfs2/aops.c

@@ -465,7 +465,7 @@ static int gfs2_read_folio(struct file *file, struct folio *folio)
 		error = mpage_read_folio(folio, gfs2_block_map);
 	}
 
-	if (unlikely(gfs2_withdrawn(sdp)))
+	if (gfs2_withdrawing_or_withdrawn(sdp))
 		return -EIO;
 
 	return error;

fs/gfs2/bmap.c

@@ -1821,7 +1821,7 @@ static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length)
 			gfs2_assert_withdraw(sdp, bh);
 			if (gfs2_assert_withdraw(sdp,
 						 prev_bnr != bh->b_blocknr)) {
-				fs_emerg(sdp, "inode %llu, block:%llu, i_h:%u,"
+				fs_emerg(sdp, "inode %llu, block:%llu, i_h:%u, "
 					 "s_h:%u, mp_h:%u\n",
 				       (unsigned long long)ip->i_no_addr,
 				       prev_bnr, ip->i_height, strip_h, mp_h);

fs/gfs2/file.c

@@ -1416,6 +1416,7 @@ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
 	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	int ret;
 
 	if (!(fl->fl_flags & FL_POSIX))
 		return -ENOLCK;
@@ -1424,17 +1425,23 @@ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
 		cmd = F_SETLK;
 		fl->fl_type = F_UNLCK;
 	}
-	if (unlikely(gfs2_withdrawn(sdp))) {
+	if (gfs2_withdrawing_or_withdrawn(sdp)) {
 		if (fl->fl_type == F_UNLCK)
 			locks_lock_file_wait(file, fl);
 		return -EIO;
 	}
-	if (IS_GETLK(cmd))
-		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
-	else if (fl->fl_type == F_UNLCK)
-		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
-	else
-		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
+	down_read(&ls->ls_sem);
+	ret = -ENODEV;
+	if (likely(ls->ls_dlm != NULL)) {
+		if (IS_GETLK(cmd))
+			ret = dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
+		else if (fl->fl_type == F_UNLCK)
+			ret = dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
+		else
+			ret = dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
+	}
+	up_read(&ls->ls_sem);
+	return ret;
 }
 
 static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh)