Example output:
./mdadm --assemble /dev/md0 /dev/sd[c-f] /dev/sdb1
mdadm: /dev/md0 has been started with 4 drives and 1 cache.
mdadm checks superblock for cache devices. If the
array appears to have a cache device, but it is not given,
it will complain as
./mdadm --assemble /dev/md0 /dev/sd[c-f]
mdadm: Not safe to assemble with cache device missing, consider --force.
This can be overwritten with --force
./mdadm --assemble /dev/md0 /dev/sd[c-f] --force
mdadm: Force start with missing cache device...
mdadm: /dev/md0 has been started with 4 drives.
Signed-off-by: Song Liu <songliubraving@xxxxxx>
---
Assemble.c | 52 ++++++++++++++++++++++++++++++++++++++++++----------
mdadm.h | 2 ++
super1.c | 22 ++++++++++++++++++++++
util.c | 3 ++-
4 files changed, 68 insertions(+), 11 deletions(-)
diff --git a/Assemble.c b/Assemble.c
index 25a103d..ccf142e 100644
--- a/Assemble.c
+++ b/Assemble.c
@@ -718,7 +718,8 @@ static int load_devices(struct devs *devices, char *devmap,
i = devcnt;
else
i = devices[devcnt].i.disk.raid_disk;
- if (i+1 == 0) {
+
+ if (i+1 == 0 || i == 0xfffd) {
if (nextspare < content->array.raid_disks*2)
nextspare = content->array.raid_disks*2;
i = nextspare++;
@@ -772,8 +773,9 @@ static int load_devices(struct devs *devices, char *devmap,
}
if (best[i] == -1
|| (devices[best[i]].i.events
- < devices[devcnt].i.events))
+ < devices[devcnt].i.events)) {
best[i] = devcnt;
+ }
}
devcnt++;
}
@@ -927,6 +929,7 @@ static int start_array(int mdfd,
unsigned int okcnt,
unsigned int sparecnt,
unsigned int rebuilding_cnt,
+ unsigned int cachecnt,
struct context *c,
int clean, char *avail,
int start_partial_ok,
@@ -938,6 +941,22 @@ static int start_array(int mdfd,
int i;
unsigned int req_cnt;
+ if (st->ss->require_cache) {
+ rv = st->ss->require_cache(st);
+ if (rv == 2) {
+ pr_err("BUG: Superblock not loaded in Assemble.c:start_array\n");
+ return 1;
+ }
+
+ if (cachecnt == 0 && rv == 1) {
+ if (!(c->force)) {
+ pr_err("Not safe to assemble with cache device missing, consider --force.\n");
+ return 1;
+ } else
+ pr_err("Force start with missing cache device...\n");
+ }
+ }
+
rv = set_array_info(mdfd, st, content);
if (rv && !err_ok) {
pr_err("failed to set array info for %s: %s\n",
@@ -1015,7 +1034,8 @@ static int start_array(int mdfd,
if (content->array.level == LEVEL_CONTAINER) {
if (c->verbose >= 0) {
pr_err("Container %s has been assembled with %d drive%s",
- mddev, okcnt+sparecnt, okcnt+sparecnt==1?"":"s");
+ mddev, okcnt+sparecnt+cachecnt,
+ okcnt+sparecnt+cachecnt==1?"":"s");
if (okcnt < (unsigned)content->array.raid_disks)
fprintf(stderr, " (out of %d)",
content->array.raid_disks);
@@ -1101,6 +1121,8 @@ static int start_array(int mdfd,
fprintf(stderr, "%s %d rebuilding", sparecnt?",":" and", rebuilding_cnt);
if (sparecnt)
fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
+ if (cachecnt == 1)
+ fprintf(stderr, " and 1 cache");
fprintf(stderr, ".\n");
}
if (content->reshape_active &&
@@ -1268,7 +1290,7 @@ int Assemble(struct supertype *st, char *mddev,
int *best = NULL; /* indexed by raid_disk */
int bestcnt = 0;
int devcnt;
- unsigned int okcnt, sparecnt, rebuilding_cnt, replcnt;
+ unsigned int okcnt, sparecnt, rebuilding_cnt, replcnt, cachecnt;
int i;
int was_forced = 0;
int most_recent = 0;
@@ -1479,6 +1501,7 @@ try_again:
devcnt = load_devices(devices, devmap, ident, &st, devlist,
c, content, mdfd, mddev,
&most_recent, &bestcnt, &best, inargv);
+
if (devcnt < 0)
return 1;
@@ -1506,7 +1529,9 @@ try_again:
okcnt = 0;
replcnt = 0;
sparecnt=0;
+ cachecnt=0;
rebuilding_cnt=0;
+
for (i=0; i< bestcnt; i++) {
int j = best[i];
int event_margin = 1; /* always allow a difference of '1'
@@ -1516,8 +1541,10 @@ try_again:
/* note: we ignore error flags in multipath arrays
* as they don't make sense
*/
- if (content->array.level != LEVEL_MULTIPATH)
- if (!(devices[j].i.disk.state & (1<<MD_DISK_ACTIVE))) {
+ if (content->array.level != LEVEL_MULTIPATH) {
+ if (devices[j].i.disk.state & (1<<MD_DISK_WRITECACHE)) {
+ cachecnt++;
+ } else if (!(devices[j].i.disk.state & (1<<MD_DISK_ACTIVE))) {
if (!(devices[j].i.disk.state
& (1<<MD_DISK_FAULTY))) {
devices[j].uptodate = 1;
@@ -1525,6 +1552,7 @@ try_again:
}
continue;
}
+ }
/* If this device thinks that 'most_recent' has failed, then
* we must reject this device.
*/
@@ -1559,10 +1587,11 @@ try_again:
replcnt++;
} else
rebuilding_cnt++;
- } else
+ } else if (devices[j].i.disk.raid_disk != 0xfffd)
sparecnt++;
}
}
+
free(devmap);
if (c->force) {
int force_ok = force_array(content, devices, best, bestcnt,
@@ -1583,8 +1612,9 @@ try_again:
int j = best[i];
int fd;
- if (j<0)
+ if (j<0) {
continue;
+ }
if (!devices[j].uptodate)
continue;
if (devices[j].i.events < devices[most_recent].i.events)
@@ -1623,7 +1653,9 @@ try_again:
int j = best[i];
unsigned int desired_state;
- if (i >= content->array.raid_disks * 2)
+ if (devices[j].i.disk.raid_disk == 0xfffd)
+ desired_state = (1<<MD_DISK_WRITECACHE);
+ else if (i >= content->array.raid_disks * 2)
desired_state = 0;
else if (i & 1)
desired_state = (1<<MD_DISK_ACTIVE) | (1<<MD_DISK_REPLACEMENT);
@@ -1770,7 +1802,7 @@ try_again:
rv = start_array(mdfd, mddev, content,
st, ident, best, bestcnt,
chosen_drive, devices, okcnt, sparecnt,
- rebuilding_cnt,
+ rebuilding_cnt, cachecnt,
c,
clean, avail, start_partial_ok,
pre_exist != NULL,
diff --git a/mdadm.h b/mdadm.h
index d7a205c..62a0293 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -971,6 +971,8 @@ extern struct superswitch {
/* write super block of raid5-cache*/
int (*write_r5l_super)(struct supertype *st, int fd);
+ /* whether the array require a cache device */
+ int (*require_cache)(struct supertype *st);
int swapuuid; /* true if uuid is bigending rather than hostendian */
int external;
const char *name; /* canonical metadata name */
diff --git a/super1.c b/super1.c
index f2697a8..c345a40 100644
--- a/super1.c
+++ b/super1.c
@@ -135,6 +135,27 @@ struct misc_dev_info {
)
static int write_r5l_super1(struct supertype *st, int fd);
+/* return value:
+ * 0, cache not required
+ * 1, cache required
+ * 2, no superblock loated (st->sb == NULL)
+ */
+static int require_cache1(struct supertype *st)
+{
+ struct mdp_superblock_1 *sb = st->sb;
+ int i;
+ if (sb)
+ for (i=0; i<MAX_DEVS; i++) {
+ if (0xFFFD == sb->dev_roles[i])
+ return 1;
+ }
+ else
+ return 2; /* no sb loaded */
+ return 0;
+}
+
+static int write_r5l_super1(struct supertype *st, int fd);
+
static int role_from_sb(struct mdp_superblock_1 *sb)
{
unsigned int d;
@@ -2556,6 +2577,7 @@ struct superswitch super1 = {
.write_bitmap = write_bitmap1,
.free_super = free_super1,
.write_r5l_super = write_r5l_super1,
+ .require_cache = require_cache1,
#if __BYTE_ORDER == BIG_ENDIAN
.swapuuid = 0,
#else
diff --git a/util.c b/util.c
index cc98d3b..f314748 100644
--- a/util.c
+++ b/util.c
@@ -334,8 +334,9 @@ int enough(int level, int raid_disks, int layout, int clean, char *avail)
int i;
int avail_disks = 0;
- for (i = 0; i < raid_disks; i++)
+ for (i = 0; i < raid_disks; i++) {
avail_disks += !!avail[i];
+ }
switch (level) {
case 10:
--
1.8.1
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
