From: johann <johann>
Date: Fri, 7 Mar 2008 07:57:04 +0000 (+0000)
Subject: Branch HEAD
X-Git-Tag: v1_7_0_51~155
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=3b6b93c54e1fa99af9d1ef9094de1c68beea8614;p=fs%2Flustre-release.git

Branch HEAD
b=14648
i=adilger
i=bobijam

when available, use the Adler-32 algorithm instead of CRC32 for
page checksums.
---

diff --git a/lustre/ChangeLog b/lustre/ChangeLog
index 27cfdd9..45e8399 100644
--- a/lustre/ChangeLog
+++ b/lustre/ChangeLog
@@ -798,6 +798,12 @@ Details    : add support for several checksum algorithm. Currently, only CRC32
 	     and Adler-32 are supported. The checksum type can be changed on
 	     the fly via /proc/fs/lustre/osc/*/checksum_type.
 
+Severity   : normal
+Bugzilla   : 14648
+Description: use adler32 for page checksums
+Details    : when available, use the Adler-32 algorithm instead of CRC32 for
+	     page checksums.
+
 --------------------------------------------------------------------------------
 
 2007-08-10         Cluster File Systems, Inc. <info@clusterfs.com>
diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index 805ac4b..3b96985 100644
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -171,7 +171,11 @@ void ll_truncate(struct inode *inode)
                         if (llap != NULL) {
                                 char *kaddr = kmap_atomic(page, KM_USER0);
                                 llap->llap_checksum =
-                                        crc32_le(0, kaddr, CFS_PAGE_SIZE);
+                                        init_checksum(OSC_DEFAULT_CKSUM);
+                                llap->llap_checksum =
+                                        compute_checksum(llap->llap_checksum,
+                                                         kaddr, CFS_PAGE_SIZE,
+                                                         OSC_DEFAULT_CKSUM);
                                 kunmap_atomic(kaddr, KM_USER0);
                         }
                         page_cache_release(page);
@@ -643,9 +647,11 @@ struct ll_async_page *llap_from_page(struct page *page, unsigned origin)
 
  out:
         if (unlikely(sbi->ll_flags & LL_SBI_CHECKSUM)) {
-                __u32 csum = 0;
+                __u32 csum;
                 char *kaddr = kmap_atomic(page, KM_USER0);
-                csum = crc32_le(csum, kaddr, CFS_PAGE_SIZE);
+                csum = init_checksum(OSC_DEFAULT_CKSUM);
+                csum = compute_checksum(csum, kaddr, CFS_PAGE_SIZE,
+                                        OSC_DEFAULT_CKSUM);
                 kunmap_atomic(kaddr, KM_USER0);
                 if (origin == LLAP_ORIGIN_READAHEAD ||
                     origin == LLAP_ORIGIN_READPAGE) {
@@ -715,10 +721,12 @@ static int queue_or_sync_write(struct obd_export *exp, struct inode *inode,
         /* compare the checksum once before the page leaves llite */
         if (unlikely((sbi->ll_flags & LL_SBI_CHECKSUM) &&
                      llap->llap_checksum != 0)) {
-                __u32 csum = 0;
+                __u32 csum;
                 struct page *page = llap->llap_page;
                 char *kaddr = kmap_atomic(page, KM_USER0);
-                csum = crc32_le(csum, kaddr, CFS_PAGE_SIZE);
+                csum = init_checksum(OSC_DEFAULT_CKSUM);
+                csum = compute_checksum(csum, kaddr, CFS_PAGE_SIZE,
+                                        OSC_DEFAULT_CKSUM);
                 kunmap_atomic(kaddr, KM_USER0);
                 if (llap->llap_checksum == csum) {
                         CDEBUG(D_PAGE, "page %p cksum %x confirmed\n",