New tag 2.15.63

[fs/lustre-release.git] / lustre / obdclass / integrity.c

diff --git a/lustre/obdclass/integrity.c b/lustre/obdclass/integrity.c
index 1ccec8a..81b9d11 100644 (file)
--- a/lustre/obdclass/integrity.c
+++ b/lustre/obdclass/integrity.c
@@ -45,38 +45,40 @@ __be16 obd_dif_ip_fn(void *data, unsigned int len)
 EXPORT_SYMBOL(obd_dif_ip_fn);
 
 int obd_page_dif_generate_buffer(const char *obd_name, struct page *page,
-                                __u32 offset, __u32 length,
+                                __u32 start, __u32 length,
                                 __be16 *guard_start, int guard_number,
                                 int *used_number, int sector_size,
                                 obd_dif_csum_fn *fn)
 {
-       unsigned int i = offset;
-       unsigned int end = offset + length;
+       unsigned int off = start;
+       unsigned int end = start + length;
        char *data_buf;
        __be16 *guard_buf = guard_start;
        unsigned int data_size;
-       int used = 0;
+       int guard_used = 0;
+       int rc = 0;
 
-       data_buf = kmap(page) + offset;
-       while (i < end) {
-               if (used >= guard_number) {
-                       CERROR("%s: unexpected used guard number of DIF %u/%u, "
-                              "data length %u, sector size %u: rc = %d\n",
-                              obd_name, used, guard_number, length,
-                              sector_size, -E2BIG);
-                       return -E2BIG;
+       data_buf = kmap(page) + start;
+       while (off < end) {
+               if (guard_used >= guard_number) {
+                       rc = -E2BIG;
+                       CERROR("%s: used %u >= guard %u, data %u+%u, sector_size %u: rc = %d\n",
+                              obd_name, guard_used, guard_number, start,
+                              length, sector_size, rc);
+                       goto out;
                }
-               data_size = min(round_up(i + 1, sector_size), end) - i;
+               data_size = min(round_up(off + 1, sector_size), end) - off;
                *guard_buf = fn(data_buf, data_size);
                guard_buf++;
+               guard_used++;
                data_buf += data_size;
-               i += data_size;
-               used++;
+               off += data_size;
        }
+       *used_number = guard_used;
+out:
        kunmap(page);
-       *used_number = used;
 
-       return 0;
+       return rc;
 }
 EXPORT_SYMBOL(obd_page_dif_generate_buffer);