[Cluster-devel] [PATCH v3 4/6] gfs2: Replace kmap_atomic() by kmap_local_page() in lops.c

[Deepak R Varma]

kmap_atomic() is deprecated in favor of kmap_local_{folio,page}().

Therefore, replace kmap_atomic() with kmap_local_page() in following
functions of lops.c:
   - gfs2_jhead_pg_srch()
   - gfs2_check_magic()
   - gfs2_before_commit()

kmap_atomic() disables page-faults and preemption (the latter only for
!PREEMPT_RT kernels), However, the code within the mapping/un-mapping in
stuffed_readpage() does not depend on the above-mentioned side effects.

Therefore, a mere replacement of the old API with the new one is all that
is required (i.e., there is no need to explicitly add any calls to
pagefault_disable() and/or preempt_disable()).

Suggested-by: Fabio M. De Francesco <fmdefrance...@gmail.com>
Signed-off-by: Deepak R Varma <d...@mailo.com>
---
Changes in v3:
   - Patch included in patch series

Changes in v2:
   - None


 fs/gfs2/lops.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 1902413d5d12..a7c2296cb3c6 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -427,7 +427,7 @@ static bool gfs2_jhead_pg_srch(struct gfs2_jdesc *jd,
 {
        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
        struct gfs2_log_header_host lh;
-       void *kaddr = kmap_atomic(page);
+       void *kaddr = kmap_local_page(page);
        unsigned int offset;
        bool ret = false;
 
@@ -441,7 +441,7 @@ static bool gfs2_jhead_pg_srch(struct gfs2_jdesc *jd,
                        }
                }
        }
-       kunmap_atomic(kaddr);
+       kunmap_local(kaddr);
        return ret;
 }
 
@@ -626,11 +626,11 @@ static void gfs2_check_magic(struct buffer_head *bh)
        __be32 *ptr;
 
        clear_buffer_escaped(bh);
-       kaddr = kmap_atomic(bh->b_page);
+       kaddr = kmap_local_page(bh->b_page);
        ptr = kaddr + bh_offset(bh);
        if (*ptr == cpu_to_be32(GFS2_MAGIC))
                set_buffer_escaped(bh);
-       kunmap_atomic(kaddr);
+       kunmap_local(kaddr);
 }
 
 static int blocknr_cmp(void *priv, const struct list_head *a,
@@ -699,10 +699,10 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, 
unsigned int limit,
                                void *kaddr;
                                page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
                                ptr = page_address(page);
-                               kaddr = kmap_atomic(bd2->bd_bh->b_page);
+                               kaddr = kmap_local_page(bd2->bd_bh->b_page);
                                memcpy(ptr, kaddr + bh_offset(bd2->bd_bh),
                                       bd2->bd_bh->b_size);
-                               kunmap_atomic(kaddr);
+                               kunmap_local(kaddr);
                                *(__be32 *)ptr = 0;
                                clear_buffer_escaped(bd2->bd_bh);
                                unlock_buffer(bd2->bd_bh);
-- 
2.34.1