DDF: differentiate between new metadata and metadata updates.

When writing an update, we don't need to overwrite lots of
empty fields.  This makes updates somewhat faster.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/super-ddf.c b/super-ddf.c
index ac914575fcd8bbaada3910469eaf46ae31b333cb..65472a285ec193374802e626d37ae834833c8234 100644 (file)
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -2820,7 +2820,8 @@ static int remove_from_super_ddf(struct supertype *st, mdu_disk_info_t *dk)
 #define NULL_CONF_SZ   4096
 
 static char *null_aligned;
-static int __write_ddf_structure(struct dl *d, struct ddf_super *ddf, __u8 type)
+static int __write_ddf_structure(struct dl *d, struct ddf_super *ddf, __u8 type,
+                                int update)
 {
        unsigned long long sector;
        struct ddf_header *header;
@@ -2897,7 +2898,7 @@ static int __write_ddf_structure(struct dl *d, struct ddf_super *ddf, __u8 type)
                        vdc->crc = calc_crc(vdc, conf_size);
                        if (write(fd, vdc, conf_size) < 0)
                                break;
-               } else {
+               } else if (!update) {
                        unsigned int togo = conf_size;
                        while (togo > NULL_CONF_SZ) {
                                if (write(fd, null_aligned, NULL_CONF_SZ) < 0)
@@ -2927,7 +2928,8 @@ out:
        return ret;
 }
 
-static int _write_super_to_disk(struct ddf_super *ddf, struct dl *d)
+static int _write_super_to_disk(struct ddf_super *ddf, struct dl *d,
+                               int update)
 {
        unsigned long long size;
        int fd = d->fd;
@@ -2965,10 +2967,10 @@ static int _write_super_to_disk(struct ddf_super *ddf, struct dl *d)
        ddf->anchor.seq = cpu_to_be32(0xFFFFFFFF); /* no sequencing in anchor */
        ddf->anchor.crc = calc_crc(&ddf->anchor, 512);
 
-       if (!__write_ddf_structure(d, ddf, DDF_HEADER_PRIMARY))
+       if (!__write_ddf_structure(d, ddf, DDF_HEADER_PRIMARY, update))
                return 0;
 
-       if (!__write_ddf_structure(d, ddf, DDF_HEADER_SECONDARY))
+       if (!__write_ddf_structure(d, ddf, DDF_HEADER_SECONDARY, update))
                return 0;
 
        lseek64(fd, (size-1)*512, SEEK_SET);
@@ -2979,7 +2981,7 @@ static int _write_super_to_disk(struct ddf_super *ddf, struct dl *d)
 }
 
 #ifndef MDASSEMBLE
-static int __write_init_super_ddf(struct supertype *st)
+static int __write_init_super_ddf(struct supertype *st, int update)
 {
        struct ddf_super *ddf = st->sb;
        struct dl *d;
@@ -2993,7 +2995,7 @@ static int __write_init_super_ddf(struct supertype *st)
         */
        for (d = ddf->dlist; d; d=d->next) {
                attempts++;
-               successes += _write_super_to_disk(ddf, d);
+               successes += _write_super_to_disk(ddf, d, update);
        }
 
        return attempts != successes;
@@ -3054,7 +3056,7 @@ static int write_init_super_ddf(struct supertype *st)
                if (!currentconf)
                        for (d = ddf->dlist; d; d=d->next)
                                while (Kill(d->devname, NULL, 0, -1, 1) == 0);
-               return __write_init_super_ddf(st);
+               return __write_init_super_ddf(st, 0);
        }
 }
 
@@ -3798,7 +3800,7 @@ static int store_super_ddf(struct supertype *st, int fd)
                }
                ofd = dl->fd;
                dl->fd = fd;
-               ret = (_write_super_to_disk(ddf, dl) != 1);
+               ret = (_write_super_to_disk(ddf, dl, 0) != 1);
                dl->fd = ofd;
                return ret;
        }
@@ -4254,7 +4256,7 @@ static void ddf_sync_metadata(struct supertype *st)
        if (!ddf->updates_pending)
                return;
        ddf->updates_pending = 0;
-       __write_init_super_ddf(st);
+       __write_init_super_ddf(st, 1);
        dprintf("ddf: sync_metadata\n");
 }