From: Nathaniel Clark <nathaniel.l.clark@intel.com>
Date: Fri, 10 Jan 2014 22:08:19 +0000 (-0500)
Subject: LU-4472 mdc: Fix mdc_page_locate ASSERT
X-Git-Tag: 2.5.56~25
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=dbb6623ef78a60c4fe71e798d52f8ec37281c12f;p=fs%2Flustre-release.git

LU-4472 mdc: Fix mdc_page_locate ASSERT

Storing hash 0 at same as hash 1 should be okay, don't ASSERT in this
case.

Signed-off-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Change-Id: I9b9488e5374d22dcfc9e7f2c969da3b02778097a
Reviewed-on: http://review.whamcloud.com/8821
Tested-by: Jenkins
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Peng Tao <bergwolf@gmail.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
---

diff --git a/lustre/liblustre/llite_lib.h b/lustre/liblustre/llite_lib.h
index 82b5b48..cc12ddf 100644
--- a/lustre/liblustre/llite_lib.h
+++ b/lustre/liblustre/llite_lib.h
@@ -442,9 +442,7 @@ static inline __u64 hash_x_index(__u64 hash, int hash64)
 {
 	if (BITS_PER_LONG == 32 && hash64)
 		hash >>= 32;
-	/* save hash 0 as index 0 because otherwise we'll save it at
-	 * page index end (~0UL) and it causes truncate_inode_pages_range()
-	 * to loop forever. */
+	/* save hash 0 with hash 1 */
 	return ~0ULL - (hash + !hash);
 }
 #endif
diff --git a/lustre/mdc/mdc_internal.h b/lustre/mdc/mdc_internal.h
index cc2816b..a49e9cd 100644
--- a/lustre/mdc/mdc_internal.h
+++ b/lustre/mdc/mdc_internal.h
@@ -179,10 +179,7 @@ static inline unsigned long hash_x_index(__u64 hash, int hash64)
 	if (BITS_PER_LONG == 32 && hash64)
 		hash >>= 32;
 #endif
-	/* save hash 0 as index 0 because otherwise we'll save it at
-	 * page index end (~0UL) and it causes truncate_inode_pages_range()
-	 * to loop forever.
-	 */
+	/* save hash 0 with hash 1 */
 	return ~0UL - (hash + !hash);
 }
 
diff --git a/lustre/mdc/mdc_request.c b/lustre/mdc/mdc_request.c
index e111015..1503bf9 100644
--- a/lustre/mdc/mdc_request.c
+++ b/lustre/mdc/mdc_request.c
@@ -1233,8 +1233,12 @@ static struct page *mdc_page_locate(struct address_space *mapping, __u64 *hash,
 				*start = le64_to_cpu(dp->ldp_hash_start);
 				*end   = le64_to_cpu(dp->ldp_hash_end);
 			}
-			LASSERTF(*start <= *hash, "start = "LPX64",end = "
-				 LPX64",hash = "LPX64"\n", *start, *end, *hash);
+			if (unlikely(*start == 1 && *hash == 0))
+				*hash = *start;
+			else
+				LASSERTF(*start <= *hash, "start = "LPX64
+					 ",end = "LPX64",hash = "LPX64"\n",
+					 *start, *end, *hash);
 			CDEBUG(D_VFSTRACE, "page%lu [%llu %llu], hash"LPU64"\n",
 			       offset, *start, *end, *hash);
 			if (*hash > *end) {