LU-5631 obdclass: Proper swabbing of llog_rec_tail.

A variable-length structure preceeds llog_rec_tail within an llog
block. Thus cr_tail shouldn't be accessed directly as a structure
member but its actual location should be computed dynamically.

Signed-off-by: Henri Doreau <henri.doreau@cea.fr>
Change-Id: I2d244797d107cf52f647e19b2db780138e910925
Reviewed-on: http://review.whamcloud.com/11953
Tested-by: Jenkins
Reviewed-by: jacques-Charles Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>

diff --git a/lustre/obdclass/llog_swab.c b/lustre/obdclass/llog_swab.c
index 1ef4d96..9cbffef 100644 (file)
--- a/lustre/obdclass/llog_swab.c
+++ b/lustre/obdclass/llog_swab.c
@@ -135,32 +135,32 @@ void lustre_swab_llog_rec(struct llog_rec_hdr *rec)
 {
        struct llog_rec_tail *tail = NULL;
 
-        __swab32s(&rec->lrh_len);
-        __swab32s(&rec->lrh_index);
-        __swab32s(&rec->lrh_type);
+       __swab32s(&rec->lrh_len);
+       __swab32s(&rec->lrh_index);
+       __swab32s(&rec->lrh_type);
        __swab32s(&rec->lrh_id);
 
-        switch (rec->lrh_type) {
+       switch (rec->lrh_type) {
        case OST_SZ_REC:
        {
-                struct llog_size_change_rec *lsc =
-                        (struct llog_size_change_rec *)rec;
+               struct llog_size_change_rec *lsc =
+                       (struct llog_size_change_rec *)rec;
 
-                lustre_swab_ll_fid(&lsc->lsc_fid);
-                __swab32s(&lsc->lsc_ioepoch);
+               lustre_swab_ll_fid(&lsc->lsc_fid);
+               __swab32s(&lsc->lsc_ioepoch);
                tail = &lsc->lsc_tail;
-                break;
-        }
+               break;
+       }
        case MDS_UNLINK_REC:
        {
-                struct llog_unlink_rec *lur = (struct llog_unlink_rec *)rec;
+               struct llog_unlink_rec *lur = (struct llog_unlink_rec *)rec;
 
-                __swab64s(&lur->lur_oid);
-                __swab32s(&lur->lur_oseq);
-                __swab32s(&lur->lur_count);
+               __swab64s(&lur->lur_oid);
+               __swab32s(&lur->lur_oseq);
+               __swab32s(&lur->lur_count);
                tail = &lur->lur_tail;
-                break;
-        }
+               break;
+       }
        case MDS_UNLINK64_REC:
        {
                struct llog_unlink64_rec *lur =
@@ -173,16 +173,17 @@ void lustre_swab_llog_rec(struct llog_rec_hdr *rec)
        }
        case CHANGELOG_REC:
        {
-                struct llog_changelog_rec *cr = (struct llog_changelog_rec*)rec;
-
-                __swab16s(&cr->cr.cr_namelen);
-                __swab16s(&cr->cr.cr_flags);
-                __swab32s(&cr->cr.cr_type);
-                __swab64s(&cr->cr.cr_index);
-                __swab64s(&cr->cr.cr_prev);
-                __swab64s(&cr->cr.cr_time);
-                lustre_swab_lu_fid(&cr->cr.cr_tfid);
-                lustre_swab_lu_fid(&cr->cr.cr_pfid);
+               struct llog_changelog_rec *cr =
+                       (struct llog_changelog_rec *)rec;
+
+               __swab16s(&cr->cr.cr_namelen);
+               __swab16s(&cr->cr.cr_flags);
+               __swab32s(&cr->cr.cr_type);
+               __swab64s(&cr->cr.cr_index);
+               __swab64s(&cr->cr.cr_prev);
+               __swab64s(&cr->cr.cr_time);
+               lustre_swab_lu_fid(&cr->cr.cr_tfid);
+               lustre_swab_lu_fid(&cr->cr.cr_pfid);
                if (CHANGELOG_REC_EXTENDED(&cr->cr)) {
                        struct llog_changelog_ext_rec *ext =
                                (struct llog_changelog_ext_rec *)rec;
@@ -193,18 +194,20 @@ void lustre_swab_llog_rec(struct llog_rec_hdr *rec)
                } else {
                        tail = &cr->cr_tail;
                }
-                break;
-        }
+               tail = (struct llog_rec_tail *)((char *)tail +
+                                               cr->cr.cr_namelen);
+               break;
+       }
        case CHANGELOG_USER_REC:
        {
-                struct llog_changelog_user_rec *cur =
-                        (struct llog_changelog_user_rec*)rec;
+               struct llog_changelog_user_rec *cur =
+                       (struct llog_changelog_user_rec *)rec;
 
-                __swab32s(&cur->cur_id);
-                __swab64s(&cur->cur_endrec);
+               __swab32s(&cur->cur_id);
+               __swab64s(&cur->cur_endrec);
                tail = &cur->cur_tail;
-                break;
-        }
+               break;
+       }
 
        case HSM_AGENT_REC: {
                struct llog_agent_req_rec *arr =
@@ -236,23 +239,23 @@ void lustre_swab_llog_rec(struct llog_rec_hdr *rec)
                __swab64s(&lsr->lsr_valid);
                tail = &lsr->lsr_tail;
                break;
-        }
-        case OBD_CFG_REC:
-                /* these are swabbed as they are consumed */
-                break;
+       }
+       case OBD_CFG_REC:
+               /* these are swabbed as they are consumed */
+               break;
        case LLOG_HDR_MAGIC:
        {
-                struct llog_log_hdr *llh = (struct llog_log_hdr *)rec;
-
-                __swab64s(&llh->llh_timestamp);
-                __swab32s(&llh->llh_count);
-                __swab32s(&llh->llh_bitmap_offset);
-                __swab32s(&llh->llh_flags);
-                __swab32s(&llh->llh_size);
-                __swab32s(&llh->llh_cat_idx);
+               struct llog_log_hdr *llh = (struct llog_log_hdr *)rec;
+
+               __swab64s(&llh->llh_timestamp);
+               __swab32s(&llh->llh_count);
+               __swab32s(&llh->llh_bitmap_offset);
+               __swab32s(&llh->llh_flags);
+               __swab32s(&llh->llh_size);
+               __swab32s(&llh->llh_cat_idx);
                tail = &llh->llh_tail;
-                break;
-        }
+               break;
+       }
        case LLOG_LOGID_MAGIC:
        {
                struct llog_logid_rec *lid = (struct llog_logid_rec *)rec;
@@ -270,17 +273,17 @@ void lustre_swab_llog_rec(struct llog_rec_hdr *rec)
                tail = &lgr->lgr_tail;
                break;
        }
-        case LLOG_PAD_MAGIC:
-                break;
-        default:
-                CERROR("Unknown llog rec type %#x swabbing rec %p\n",
-                       rec->lrh_type, rec);
-        }
+       case LLOG_PAD_MAGIC:
+               break;
+       default:
+               CERROR("Unknown llog rec type %#x swabbing rec %p\n",
+                      rec->lrh_type, rec);
+       }
 
-        if (tail) {
-                __swab32s(&tail->lrt_len);
-                __swab32s(&tail->lrt_index);
-        }
+       if (tail) {
+               __swab32s(&tail->lrt_len);
+               __swab32s(&tail->lrt_index);
+       }
 }
 EXPORT_SYMBOL(lustre_swab_llog_rec);