LU-827 lov: Implement a per file data_version.

This patch extends getattr RPC to also send in its reply a data
version for the file content.  This only tracks data object changes.
This does not track chown/chmod on OST object.  This value is intended
to be only compared for equality.  A new call in liblustreapi is
available and through 'lfs data_version'.

Signed-off-by: Aurelien Degremont <aurelien.degremont@cea.fr>
Signed-off-by: Johann Lombardi <johann@whamcloud.com>
Change-Id: I5d748e096b11627c05f86ef6f3f6906bce120893
Reviewed-on: http://review.whamcloud.com/1671
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/doc/lfs.1 b/lustre/doc/lfs.1
index 5953ad4..d5d8d44 100644 (file)
--- a/lustre/doc/lfs.1
+++ b/lustre/doc/lfs.1
@@ -74,6 +74,8 @@ lfs \- Lustre utility to create a file with specific striping pattern, find the
              \fB[-b <block-grace>] [-i <inode-grace>]
              \fB<filesystem>\fR
 .br
              \fB[-b <block-grace>] [-i <inode-grace>]
              \fB<filesystem>\fR
 .br

+.B lfs data_version [-n] \fB<filename>\fR
+.br

 .B lfs help
 .SH DESCRIPTION
 .B lfs
 .B lfs help
 .SH DESCRIPTION
 .B lfs


@@ -227,6 +229,16 @@ To set filesystem quotas for users or groups. Limits can be specified with -b, -
 .B setquota -t [-u|-g] [--block-grace <block-grace>] [--inode-grace <inode-grace>] <filesystem>
 To set filesystem quota grace times for users or groups. Grace time is specified in "XXwXXdXXhXXmXXs" format or as an integer seconds value, see EXAMPLES
 .TP
 .B setquota -t [-u|-g] [--block-grace <block-grace>] [--inode-grace <inode-grace>] <filesystem>
 To set filesystem quota grace times for users or groups. Grace time is specified in "XXwXXdXXhXXmXXs" format or as an integer seconds value, see EXAMPLES
 .TP

+.B data_version [-n] <filename>
+Display current version of file data. If -n is specified, data version is read
+without taking lock. As a consequence, data version could be outdated if there
+is dirty caches on filesystem clients, but this will not force data flushes and
+has less impact on filesystem.
+
+Even without -n, race conditions are possible and data version should be
+checked before and after an operation to be confident the data did not change
+during it.
+.TP

 .B help 
 Provides brief help on the various arguments
 .TP
 .B help 
 Provides brief help on the various arguments
 .TP

diff --git a/lustre/include/lustre/liblustreapi.h b/lustre/include/lustre/liblustreapi.h
index a528c55..331d3ee 100644 (file)
--- a/lustre/include/lustre/liblustreapi.h
+++ b/lustre/include/lustre/liblustreapi.h
@@ -223,6 +223,8 @@ extern int llapi_fid2path(const char *device, const char *fidstr, char *path,
 extern int llapi_path2fid(const char *path, lustre_fid *fid);
 extern int llapi_get_version(char *buffer, int buffer_size, char **version);
 
 extern int llapi_path2fid(const char *path, lustre_fid *fid);
 extern int llapi_get_version(char *buffer, int buffer_size, char **version);
 

+extern int llapi_get_data_version(int fd, __u64 *data_version, __u64 flags);
+

 /* Changelog interface.  priv is private state, managed internally
    by these functions */
 #define CHANGELOG_FLAG_FOLLOW 0x01   /* Not yet implemented */
 /* Changelog interface.  priv is private state, managed internally
    by these functions */
 #define CHANGELOG_FLAG_FOLLOW 0x01   /* Not yet implemented */

diff --git a/lustre/include/lustre/lustre_user.h b/lustre/include/lustre/lustre_user.h
index be69c18..51a6857 100644 (file)
--- a/lustre/include/lustre/lustre_user.h
+++ b/lustre/include/lustre/lustre_user.h
@@ -155,6 +155,7 @@ struct obd_statfs {
 #define LL_IOC_HSM_CT_START             _IOW ('f', 176,struct lustre_kernelcomm)
 /* see <lustre_lib.h> for ioctl numbers 177-210 */
 
 #define LL_IOC_HSM_CT_START             _IOW ('f', 176,struct lustre_kernelcomm)
 /* see <lustre_lib.h> for ioctl numbers 177-210 */
 

+#define LL_IOC_DATA_VERSION             _IOR ('f', 218, struct ioc_data_version)

 
 #define LL_STATFS_LMV           1
 #define LL_STATFS_LOV           2
 
 #define LL_STATFS_LMV           1
 #define LL_STATFS_LOV           2


@@ -632,6 +633,13 @@ enum changelog_message_type {
 
 /********* Misc **********/
 
 
 /********* Misc **********/
 

+struct ioc_data_version {
+        __u64 idv_version;
+        __u64 idv_flags;     /* See LL_DV_xxx */
+};
+#define LL_DV_NOFLUSH 0x01   /* Do not take READ EXTENT LOCK before sampling
+                                version. Dirty caches are left unchanged. */
+

 #ifndef offsetof
 # define offsetof(typ,memb)     ((unsigned long)((char *)&(((typ *)0)->memb)))
 #endif
 #ifndef offsetof
 # define offsetof(typ,memb)     ((unsigned long)((char *)&(((typ *)0)->memb)))
 #endif

diff --git a/lustre/include/lustre_lib.h b/lustre/include/lustre_lib.h
index a60389f..6f4cf15 100644 (file)
--- a/lustre/include/lustre_lib.h
+++ b/lustre/include/lustre_lib.h
@@ -559,6 +559,7 @@ static inline void obd_ioctl_freedata(char *buf, int len)
 
 #define OBD_IOC_GET_OBJ_VERSION        _IOR('f', 210, OBD_IOC_DATA_TYPE)
 
 
 #define OBD_IOC_GET_OBJ_VERSION        _IOR('f', 210, OBD_IOC_DATA_TYPE)
 

+/* <lustre/lustre_user.h> defines ioctl number 218 */

 #define OBD_IOC_GET_MNTOPT             _IOW('f', 220, mntopt_t)
 
 #define OBD_IOC_ECHO_MD                _IOR('f', 221, struct obd_ioctl_data)
 #define OBD_IOC_GET_MNTOPT             _IOW('f', 220, mntopt_t)
 
 #define OBD_IOC_ECHO_MD                _IOR('f', 221, struct obd_ioctl_data)

diff --git a/lustre/llite/file.c b/lustre/llite/file.c
index 231f2f3..80dcdb8 100644 (file)
--- a/lustre/llite/file.c
+++ b/lustre/llite/file.c
@@ -708,7 +708,8 @@ static int ll_lsm_getattr(struct lov_stripe_md *lsm, struct obd_export *exp,
                                OBD_MD_FLSIZE | OBD_MD_FLBLOCKS |
                                OBD_MD_FLBLKSZ | OBD_MD_FLATIME |
                                OBD_MD_FLMTIME | OBD_MD_FLCTIME |
                                OBD_MD_FLSIZE | OBD_MD_FLBLOCKS |
                                OBD_MD_FLBLKSZ | OBD_MD_FLATIME |
                                OBD_MD_FLMTIME | OBD_MD_FLCTIME |

-                               OBD_MD_FLGROUP | OBD_MD_FLEPOCH;
+                               OBD_MD_FLGROUP | OBD_MD_FLEPOCH |
+                               OBD_MD_FLDATAVERSION;

         oinfo.oi_capa = capa;
         if (sync) {
                 oinfo.oi_oa->o_valid |= OBD_MD_FLFLAGS;
         oinfo.oi_capa = capa;
         if (sync) {
                 oinfo.oi_oa->o_valid |= OBD_MD_FLFLAGS;


@@ -728,7 +729,8 @@ static int ll_lsm_getattr(struct lov_stripe_md *lsm, struct obd_export *exp,
         if (rc == 0)
                 oinfo.oi_oa->o_valid &= (OBD_MD_FLBLOCKS | OBD_MD_FLBLKSZ |
                                          OBD_MD_FLATIME | OBD_MD_FLMTIME |
         if (rc == 0)
                 oinfo.oi_oa->o_valid &= (OBD_MD_FLBLOCKS | OBD_MD_FLBLKSZ |
                                          OBD_MD_FLATIME | OBD_MD_FLMTIME |

-                                         OBD_MD_FLCTIME | OBD_MD_FLSIZE);
+                                         OBD_MD_FLCTIME | OBD_MD_FLSIZE |
+                                         OBD_MD_FLDATAVERSION);

         RETURN(rc);
 }
 
         RETURN(rc);
 }
 


@@ -1746,6 +1748,48 @@ error:
         RETURN(rc);
 }
 
         RETURN(rc);
 }
 

+/*
+ * Read the data_version for inode.
+ *
+ * This value is computed using stripe object version on OST.
+ * Version is computed using server side locking.
+ *
+ * @param extent_lock  Take extent lock. Not needed if a process is already
+ *                     holding the OST object group locks.
+ */
+static int ll_data_version(struct inode *inode, __u64 *data_version,
+                           int extent_lock)
+{
+        struct lov_stripe_md *lsm = ll_i2info(inode)->lli_smd;
+        struct ll_sb_info    *sbi = ll_i2sbi(inode);
+        struct obdo          *obdo = NULL;
+        int                   rc;
+        ENTRY;
+
+        /* If no stripe, we consider version is 0. */
+        if (!lsm) {
+                *data_version = 0;
+                CDEBUG(D_INODE, "No object for inode\n");
+                RETURN(0);
+        }
+
+        OBD_ALLOC_PTR(obdo);
+        if (obdo == NULL)
+                RETURN(-ENOMEM);
+
+        rc = ll_lsm_getattr(lsm, sbi->ll_dt_exp, NULL, obdo, 0, extent_lock);
+        if (!rc) {
+                if (!(obdo->o_valid & OBD_MD_FLDATAVERSION))
+                        rc = -EOPNOTSUPP;
+                else
+                        *data_version = obdo->o_data_version;
+        }
+
+        OBD_FREE_PTR(obdo);
+
+        RETURN(rc);
+}
+

 #ifdef HAVE_UNLOCKED_IOCTL
 long ll_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 #ifdef HAVE_UNLOCKED_IOCTL
 long ll_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {


@@ -1836,6 +1880,23 @@ int ll_file_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
         }
         case OBD_IOC_FID2PATH:
                 RETURN(ll_fid2path(ll_i2mdexp(inode), (void *)arg));
         }
         case OBD_IOC_FID2PATH:
                 RETURN(ll_fid2path(ll_i2mdexp(inode), (void *)arg));

+        case LL_IOC_DATA_VERSION: {
+                struct ioc_data_version idv;
+                int rc;
+
+                if (cfs_copy_from_user(&idv, (char *)arg, sizeof(idv)))
+                        RETURN(-EFAULT);
+
+                rc = ll_data_version(inode, &idv.idv_version,
+                                     !(idv.idv_flags & LL_DV_NOFLUSH));
+
+                if (rc == 0 &&
+                    cfs_copy_to_user((char *) arg, &idv, sizeof(idv)))
+                        RETURN(-EFAULT);
+
+                RETURN(rc);
+        }
+

         case LL_IOC_GET_MDTIDX: {
                 int mdtidx;
 
         case LL_IOC_GET_MDTIDX: {
                 int mdtidx;
 

diff --git a/lustre/lov/lov_internal.h b/lustre/lov/lov_internal.h
index 1a6b34a..e602606 100644 (file)
--- a/lustre/lov/lov_internal.h
+++ b/lustre/lov/lov_internal.h
@@ -157,7 +157,7 @@ static inline void lov_llh_put(struct lov_lock_handles *llh)
         (char *)((lv)->lov_tgts[index]->ltd_uuid.uuid)
 
 /* lov_merge.c */
         (char *)((lv)->lov_tgts[index]->ltd_uuid.uuid)
 
 /* lov_merge.c */

-void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_flag valid,
+void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_valid valid,

                      struct lov_stripe_md *lsm, int stripeno, int *set);
 int lov_merge_lvb(struct obd_export *exp, struct lov_stripe_md *lsm,
                   struct ost_lvb *lvb, int kms_only);
                      struct lov_stripe_md *lsm, int stripeno, int *set);
 int lov_merge_lvb(struct obd_export *exp, struct lov_stripe_md *lsm,
                   struct ost_lvb *lvb, int kms_only);

diff --git a/lustre/lov/lov_merge.c b/lustre/lov/lov_merge.c
index ad759c3..2f943de 100644 (file)
--- a/lustre/lov/lov_merge.c
+++ b/lustre/lov/lov_merge.c
@@ -176,7 +176,7 @@ int lov_adjust_kms(struct obd_export *exp, struct lov_stripe_md *lsm,
         RETURN(0);
 }
 
         RETURN(0);
 }
 

-void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_flag valid,
+void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_valid valid,

                      struct lov_stripe_md *lsm, int stripeno, int *set)
 {
         valid &= src->o_valid;
                      struct lov_stripe_md *lsm, int stripeno, int *set)
 {
         valid &= src->o_valid;


@@ -198,11 +198,18 @@ void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_flag valid,
                         tgt->o_ctime = src->o_ctime;
                 if (valid & OBD_MD_FLMTIME && tgt->o_mtime < src->o_mtime)
                         tgt->o_mtime = src->o_mtime;
                         tgt->o_ctime = src->o_ctime;
                 if (valid & OBD_MD_FLMTIME && tgt->o_mtime < src->o_mtime)
                         tgt->o_mtime = src->o_mtime;

+                if (valid & OBD_MD_FLDATAVERSION)
+                        tgt->o_data_version += src->o_data_version;

         } else {
                 memcpy(tgt, src, sizeof(*tgt));
                 tgt->o_id = lsm->lsm_object_id;
                 if (valid & OBD_MD_FLSIZE)
                         tgt->o_size = lov_stripe_size(lsm,src->o_size,stripeno);
         }
         } else {
                 memcpy(tgt, src, sizeof(*tgt));
                 tgt->o_id = lsm->lsm_object_id;
                 if (valid & OBD_MD_FLSIZE)
                         tgt->o_size = lov_stripe_size(lsm,src->o_size,stripeno);
         }

+
+        /* data_version needs to be valid on all stripes to be correct! */
+        if (!(valid & OBD_MD_FLDATAVERSION))
+                tgt->o_valid &= ~OBD_MD_FLDATAVERSION;
+

         *set += 1;
 }
         *set += 1;
 }

diff --git a/lustre/obdfilter/filter.c b/lustre/obdfilter/filter.c
index 9dfef42..93b6edc 100644 (file)
--- a/lustre/obdfilter/filter.c
+++ b/lustre/obdfilter/filter.c
@@ -3158,6 +3158,7 @@ static int filter_getattr(struct obd_export *exp, struct obd_info *oinfo)
 {
         struct dentry *dentry = NULL;
         struct obd_device *obd;
 {
         struct dentry *dentry = NULL;
         struct obd_device *obd;

+        __u64 curr_version;

         int rc = 0;
         ENTRY;
 
         int rc = 0;
         ENTRY;
 


@@ -3180,6 +3181,13 @@ static int filter_getattr(struct obd_export *exp, struct obd_info *oinfo)
         oinfo->oi_oa->o_valid = OBD_MD_FLID;
         obdo_from_inode(oinfo->oi_oa, dentry->d_inode, NULL, FILTER_VALID_FLAGS);
 
         oinfo->oi_oa->o_valid = OBD_MD_FLID;
         obdo_from_inode(oinfo->oi_oa, dentry->d_inode, NULL, FILTER_VALID_FLAGS);
 

+        /* Store inode version in reply */
+        curr_version = fsfilt_get_version(exp->exp_obd, dentry->d_inode);
+        if ((__s64)curr_version != -EOPNOTSUPP) {
+                oinfo->oi_oa->o_valid |= OBD_MD_FLDATAVERSION;
+                oinfo->oi_oa->o_data_version = curr_version;
+        }
+

         f_dput(dentry);
         RETURN(rc);
 }
         f_dput(dentry);
         RETURN(rc);
 }

diff --git a/lustre/ptlrpc/wiretest.c b/lustre/ptlrpc/wiretest.c
index 9aca930..7208df9 100644 (file)
--- a/lustre/ptlrpc/wiretest.c
+++ b/lustre/ptlrpc/wiretest.c
@@ -904,6 +904,8 @@ void lustre_assert_wire_constants(void)
         LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingE) == 8, "found %lld\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingE));
         LASSERTF((int)offsetof(struct obd_connect_data, paddingF) == 184, "found %lld\n",
         LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingE) == 8, "found %lld\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingE));
         LASSERTF((int)offsetof(struct obd_connect_data, paddingF) == 184, "found %lld\n",

+                 (long long)(int)offsetof(struct obd_connect_data, paddingF));
+        LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingF) == 8, "found %lld\n",

                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingF));
 
         LASSERTF(OBD_CONNECT_RDONLY == 0x1ULL, "found 0x%.16llxULL\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingF));
 
         LASSERTF(OBD_CONNECT_RDONLY == 0x1ULL, "found 0x%.16llxULL\n",

diff --git a/lustre/tests/sanityn.sh b/lustre/tests/sanityn.sh
index df7e017..56eac96 100644 (file)
--- a/lustre/tests/sanityn.sh
+++ b/lustre/tests/sanityn.sh
@@ -31,6 +31,7 @@ export TMP=${TMP:-/tmp}
 MOUNT_2=${MOUNT_2:-"yes"}
 CHECK_GRANT=${CHECK_GRANT:-"yes"}
 GRANT_CHECK_LIST=${GRANT_CHECK_LIST:-""}
 MOUNT_2=${MOUNT_2:-"yes"}
 CHECK_GRANT=${CHECK_GRANT:-"yes"}
 GRANT_CHECK_LIST=${GRANT_CHECK_LIST:-""}

+TSTUSR=${TSTUSR:-"quota_usr"}

 
 SAVE_PWD=$PWD
 
 
 SAVE_PWD=$PWD
 


@@ -1877,6 +1878,53 @@ test_50() {
 }
 run_test 50 "osc lvb attrs: enqueue vs. CP AST =============="
 
 }
 run_test 50 "osc lvb attrs: enqueue vs. CP AST =============="
 

+test_60() {
+       # Create a file
+       mkdir -p $DIR1/$tdir
+       file1=$DIR1/$tdir/file
+       file2=$DIR2/$tdir/file
+
+       echo orig > $file2 || error "Could not create $file2"
+       version=$($LFS data_version $file1)
+
+       # Append data
+       echo append >> $file2 || error "Could not append to $file2"
+       version2=$($LFS data_version $file1)
+       [ "$version" != "$version2" ] ||
+           error "append did not change data version: $version"
+
+       # Overwrite data
+       echo overwrite > $file2 || error "Could not overwrite $file2"
+       version3=$($LFS data_version $file1)
+       [ "$version2" != "$version3" ] ||
+           error "overwrite did not change data version: $version2"
+
+       # Truncate before EOF
+       $TRUNCATE $file2 3 || error "Could not truncate $file2"
+       version4=$($LFS data_version $file1)
+       [ "$version3" != "$version4" ] ||
+           error "truncate did not change data version: $version3"
+
+       # Truncate after EOF
+       $TRUNCATE $file2 123456 || error "Could not truncate $file2"
+       version5=$($LFS data_version $file1)
+       [ "$version4" != "$version5" ] ||
+           error "truncate did not change data version: $version4"
+
+       # Chmod do not change version
+       chmod 400 $file2 || error "Could not chmod 400 $file2"
+       version6=$($LFS data_version $file1)
+       [ "$version5" == "$version6" ] ||
+           error "chmod should not change data version: $version5 != $version6"
+
+       # Chown do not change version
+       chown $TSTUSR $file2 || error "Could not chown $TSTUSR $file2"
+       version7=$($LFS data_version $file1)
+       [ "$version5" == "$version7" ] ||
+           error "chown should not change data version: $version5 != $version7"
+}
+run_test 60 "Verify data_version behaviour"
+

 log "cleanup: ======================================================"
 
 [ "$(mount | grep $MOUNT2)" ] && umount $MOUNT2
 log "cleanup: ======================================================"
 
 [ "$(mount | grep $MOUNT2)" ] && umount $MOUNT2

diff --git a/lustre/utils/lfs.c b/lustre/utils/lfs.c
index 07e3ed7..a52bd08 100644 (file)
--- a/lustre/utils/lfs.c
+++ b/lustre/utils/lfs.c
@@ -114,6 +114,7 @@ static int lfs_changelog(int argc, char **argv);
 static int lfs_changelog_clear(int argc, char **argv);
 static int lfs_fid2path(int argc, char **argv);
 static int lfs_path2fid(int argc, char **argv);
 static int lfs_changelog_clear(int argc, char **argv);
 static int lfs_fid2path(int argc, char **argv);
 static int lfs_path2fid(int argc, char **argv);

+static int lfs_data_version(int argc, char **argv);

 
 /* all avaialable commands */
 command_t cmdlist[] = {
 
 /* all avaialable commands */
 command_t cmdlist[] = {


@@ -252,6 +253,8 @@ command_t cmdlist[] = {
                 /*[--rec <recno>]*/},
         {"path2fid", lfs_path2fid, 0, "Display the fid for a given path.\n"
          "usage: path2fid <path>"},
                 /*[--rec <recno>]*/},
         {"path2fid", lfs_path2fid, 0, "Display the fid for a given path.\n"
          "usage: path2fid <path>"},

+        {"data_version", lfs_data_version, 0, "Display file data version for "
+         "a given path.\n" "usage: data_version [-n] <path>"},

         {"help", Parser_help, 0, "help"},
         {"exit", Parser_quit, 0, "quit"},
         {"quit", Parser_quit, 0, "quit"},
         {"help", Parser_help, 0, "help"},
         {"exit", Parser_quit, 0, "quit"},
         {"quit", Parser_quit, 0, "quit"},


@@ -2621,6 +2624,53 @@ static int lfs_path2fid(int argc, char **argv)
         return 0;
 }
 
         return 0;
 }
 

+static int lfs_data_version(int argc, char **argv)
+{
+        char *path;
+        __u64 data_version;
+        int fd;
+        int rc;
+        int c;
+        int nolock = 0;
+
+        if (argc < 2)
+                return CMD_HELP;
+
+        optind = 0;
+        while ((c = getopt(argc, argv, "n")) != -1) {
+                switch (c) {
+                case 'n':
+                        nolock = LL_DV_NOFLUSH;
+                        break;
+                default:
+                        return CMD_HELP;
+                }
+        }
+        if (optind == argc)
+                return CMD_HELP;
+
+        path = argv[optind];
+        fd = open(path, O_RDONLY);
+        if (fd < 0) {
+                fprintf(stderr, "can't open %s: %s\n", path,
+                        strerror(errno));
+                return errno;
+        }
+
+        rc = llapi_get_data_version(fd, &data_version, nolock);
+        if (rc) {
+                fprintf(stderr, "can't get version for %s: %s\n", path,
+                        strerror(errno = -rc));
+                return rc;
+        }
+
+        printf("%llu\n", data_version);
+
+        close(fd);
+
+        return 0;
+}
+

 int main(int argc, char **argv)
 {
         int rc;
 int main(int argc, char **argv)
 {
         int rc;

diff --git a/lustre/utils/liblustreapi.c b/lustre/utils/liblustreapi.c
index e9937a9..0584319 100644 (file)
--- a/lustre/utils/liblustreapi.c
+++ b/lustre/utils/liblustreapi.c
@@ -3941,3 +3941,33 @@ int llapi_get_version(char *buffer, int buffer_size,
         *version = data->ioc_bulk;
         return 0;
 }
         *version = data->ioc_bulk;
         return 0;
 }

+
+/**
+ * Get a 64-bit value representing the version of file data pointed by fd.
+ *
+ * Each write or truncate, flushed on OST, will change this value. You can use
+ * this value to verify if file data was modified. This only checks the file
+ * data, not metadata.
+ *
+ * \param  flags  If set to LL_DV_NOFLUSH, the data version will be read
+ *                directly from OST without regard to possible dirty cache on
+ *                client nodes.
+ *
+ * \retval 0 on success.
+ * \retval -errno on error.
+ */
+int llapi_get_data_version(int fd, __u64 *data_version, __u64 flags)
+{
+        int rc;
+        struct ioc_data_version idv;
+
+        idv.idv_flags = flags;
+
+        rc = ioctl(fd, LL_IOC_DATA_VERSION, &idv);
+        if (rc)
+                rc = -errno;
+        else
+                *data_version = idv.idv_version;
+
+        return rc;
+}

diff --git a/lustre/utils/wiretest.c b/lustre/utils/wiretest.c
index 76dcca4..eceaf35 100644 (file)
--- a/lustre/utils/wiretest.c
+++ b/lustre/utils/wiretest.c
@@ -912,6 +912,8 @@ void lustre_assert_wire_constants(void)
         LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingE) == 8, "found %lld\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingE));
         LASSERTF((int)offsetof(struct obd_connect_data, paddingF) == 184, "found %lld\n",
         LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingE) == 8, "found %lld\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingE));
         LASSERTF((int)offsetof(struct obd_connect_data, paddingF) == 184, "found %lld\n",

+                 (long long)(int)offsetof(struct obd_connect_data, paddingF));
+        LASSERTF((int)sizeof(((struct obd_connect_data *)0)->paddingF) == 8, "found %lld\n",

                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingF));
 
         LASSERTF(OBD_CONNECT_RDONLY == 0x1ULL, "found 0x%.16llxULL\n",
                  (long long)(int)sizeof(((struct obd_connect_data *)0)->paddingF));
 
         LASSERTF(OBD_CONNECT_RDONLY == 0x1ULL, "found 0x%.16llxULL\n",