Support the new extensions to have a volume-id that is immutable and
unique for the life of the container. Prior to this change deleting and
recreating a volume would result in it having the same uuid as the
previous volume in that position. Now, every time a volume is created a
container generation count is incremented allowing the volume-ids to
include container generation salt.
TODO update kill_subarray_imsm() and update_subarray_imsm() to allow
deletion and renaming (respectively) of arrays with an immutable id.
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
super-intel.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++---------
1 files changed, 65 insertions(+), 12 deletions(-)
diff --git a/super-intel.c b/super-intel.c
index f0a7ab5ccc7a..07e4c68982cd 100644
--- a/super-intel.c
+++ b/super-intel.c
@@ -188,8 +188,9 @@ struct imsm_dev {
__u16 cache_policy;
__u8 cng_state;
__u8 cng_sub_state;
-#define IMSM_DEV_FILLERS 10
- __u32 filler[IMSM_DEV_FILLERS];
+ __u16 dev_id;
+ __u16 fill;
+ __u32 filler[9];
struct imsm_vol vol;
} __attribute__ ((packed));
@@ -209,8 +210,9 @@ struct imsm_super {
__u32 orig_family_num; /* 0x40 - 0x43 original family num */
__u32 pwr_cycle_count; /* 0x44 - 0x47 simulated power cycle count for array */
__u32 bbm_log_size; /* 0x48 - 0x4B - size of bad Block Mgmt Log in bytes */
-#define IMSM_FILLERS 35
- __u32 filler[IMSM_FILLERS]; /* 0x4C - 0xD7 RAID_MPB_FILLERS */
+ __u16 create_events; /* counter for generating unique ids */
+ __u16 fill1;
+ __u32 filler[34];
struct imsm_disk disk[1]; /* 0xD8 diskTbl[numDisks] */
/* here comes imsm_dev[num_raid_devs] */
/* here comes BBM logs */
@@ -1984,6 +1986,30 @@ static int match_home_imsm(struct supertype *st, char *homehost)
return -1;
}
+static void volume_uuid_from_super(struct intel_super *super, struct sha1_ctx *ctx)
+{
+ struct imsm_dev *dev = NULL;
+
+ if (super->current_vol >= 0)
+ dev = get_imsm_dev(super, super->current_vol);
+
+ if (!dev)
+ return;
+
+ /* if the container is tracking creation events then dev_id is
+ * valid and we can advertise an immutable uuid, otherwise use the
+ * old volume-position/name method
+ */
+ if (super->anchor->create_events) {
+ sha1_process_bytes(&dev->dev_id, sizeof(dev->dev_id), ctx);
+ } else {
+ __u32 vol = super->current_vol;
+
+ sha1_process_bytes(&vol, sizeof(vol), ctx);
+ sha1_process_bytes(dev->volume, MAX_RAID_SERIAL_LEN, ctx);
+ }
+}
+
static void uuid_from_super_imsm(struct supertype *st, int uuid[4])
{
/* The uuid returned here is used for:
@@ -2012,7 +2038,6 @@ static void uuid_from_super_imsm(struct supertype *st, int uuid[4])
char buf[20];
struct sha1_ctx ctx;
- struct imsm_dev *dev = NULL;
__u32 family_num;
/* some mdadm versions failed to set ->orig_family_num, in which
@@ -2025,13 +2050,7 @@ static void uuid_from_super_imsm(struct supertype *st, int uuid[4])
sha1_init_ctx(&ctx);
sha1_process_bytes(super->anchor->sig, MPB_SIG_LEN, &ctx);
sha1_process_bytes(&family_num, sizeof(__u32), &ctx);
- if (super->current_vol >= 0)
- dev = get_imsm_dev(super, super->current_vol);
- if (dev) {
- __u32 vol = super->current_vol;
- sha1_process_bytes(&vol, sizeof(vol), &ctx);
- sha1_process_bytes(dev->volume, MAX_RAID_SERIAL_LEN, &ctx);
- }
+ volume_uuid_from_super(super, &ctx);
sha1_finish_ctx(&ctx, buf);
memcpy(uuid, buf, 4*4);
}
@@ -4562,6 +4581,39 @@ static int check_name(struct intel_super *super, char *name, int quiet)
return !reason;
}
+static void new_dev_id(struct intel_super *super, struct imsm_dev *new_dev)
+{
+ struct imsm_super *mpb = super->anchor;
+ __u16 create_events, i;
+
+ /* only turn on create_events tracking for newly born
+ * containers, lest we change the uuid of live volumes (see
+ * volume_uuid_from_super())
+ */
+ create_events = __le16_to_cpu(mpb->create_events);
+ if (super->current_vol > 0 && !create_events)
+ return;
+
+ /* catch the case of create_events wrapping to an existing id in
+ * the mpb
+ */
+ do {
+ create_events++;
+ /* wrap to 1, because zero means no dev_id support */
+ if (create_events == 0)
+ create_events = 1;
+ for (i = 0; i < mpb->num_raid_devs; i++) {
+ struct imsm_dev *dev = __get_imsm_dev(mpb, i);
+
+ if (dev->dev_id == __cpu_to_le16(create_events))
+ break;
+ }
+ } while (i < mpb->num_raid_devs);
+
+ new_dev->dev_id = __cpu_to_le16(create_events);
+ mpb->create_events = __cpu_to_le16(create_events);
+}
+
static int init_super_imsm_volume(struct supertype *st, mdu_array_info_t *info,
unsigned long long size, char *name,
char *homehost, int *uuid,
@@ -4655,6 +4707,7 @@ static int init_super_imsm_volume(struct supertype *st, mdu_array_info_t *info,
return 0;
dv = xmalloc(sizeof(*dv));
dev = xcalloc(1, sizeof(*dev) + sizeof(__u32) * (info->raid_disks - 1));
+ new_dev_id(super, dev);
strncpy((char *) dev->volume, name, MAX_RAID_SERIAL_LEN);
array_blocks = calc_array_size(info->level, info->raid_disks,
info->layout, info->chunk_size,
--
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