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Add write-behind support 

Currently this includes
  --write-behind  to set level of write-behind supported
  --write-mostly  to flag devices as write-mostly.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
This commit is contained in:
Neil Brown 2005-08-09 04:25:47 +00:00
parent 586ed40547
commit dfd4d8ee42
16 changed files with 172 additions and 34 deletions
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8
Build.c
View File

@ -36,7 +36,7 @@
int Build(char *mddev, int mdfd, int chunk, int level, int layout,
int raiddisks,
mddev_dev_t devlist, int assume_clean,
char *bitmap_file, int bitmap_chunk, int delay)
char *bitmap_file, int bitmap_chunk, int write_behind, int delay)
{
/* Build a linear or raid0 arrays without superblocks
* We cannot really do any checks, we just do it.
@ -164,7 +164,9 @@ int Build(char *mddev, int mdfd, int chunk, int level, int layout,
mdu_disk_info_t disk;
disk.number = i;
disk.raid_disk = i;
disk.state = 6;
disk.state = (1<<MD_DISK_SYNC) | (1<<MD_DISK_ACTIVE);
if (dv->writemostly)
disk.state |= 1<<MD_DISK_WRITEMOSTLY;
disk.major = major(stb.st_rdev);
disk.minor = minor(stb.st_rdev);
if (ioctl(mdfd, ADD_NEW_DISK, &disk)) {
@ -192,7 +194,7 @@ int Build(char *mddev, int mdfd, int chunk, int level, int layout,
return 1;
}
if (CreateBitmap(bitmap_file, 1, NULL, bitmap_chunk,
delay, 0/* FIXME size */)) {
delay, write_behind, 0/* FIXME size */)) {
return 1;
}
bitmap_fd = open(bitmap_file, O_RDWR);

1
ChangeLog
View File

@ -1,6 +1,7 @@
Changes Prior to this release
- Support assembling from byte-swapped superblocks
metadata type "0.swap" and --update=byteorder
- write-mostly and write-behind support for raid1.
Changes Prior to 2.0-devel-3 release
- Assorted fixes for multiple bugs...

15
Create.c
View File

@ -35,7 +35,7 @@ int Create(struct supertype *st, char *mddev, int mdfd,
int chunk, int level, int layout, unsigned long size, int raiddisks, int sparedisks,
int subdevs, mddev_dev_t devlist,
int runstop, int verbose, int force,
char *bitmap_file, int bitmap_chunk, int delay)
char *bitmap_file, int bitmap_chunk, int write_behind, int delay)
{
/*
* Create a new raid array.
@ -351,7 +351,7 @@ int Create(struct supertype *st, char *mddev, int mdfd,
fprintf(stderr, Name ": internal bitmaps not supported by this kernel.\n");
return 1;
}
if (!st->ss->add_internal_bitmap(super, bitmap_chunk, delay,
if (!st->ss->add_internal_bitmap(super, bitmap_chunk, delay, write_behind,
size ? size : maxsize)) {
fprintf(stderr, Name ": Given bitmap chunk size not supported.\n");
return 1;
@ -382,7 +382,8 @@ int Create(struct supertype *st, char *mddev, int mdfd,
bitmap_chunk = DEFAULT_BITMAP_CHUNK;
st->ss->uuid_from_super(uuid, super);
if (CreateBitmap(bitmap_file, force, (char*)uuid, bitmap_chunk, delay,
if (CreateBitmap(bitmap_file, force, (char*)uuid, bitmap_chunk,
delay, write_behind,
array.size*2ULL /* FIXME wrong for raid10 */)) {
return 1;
}
@ -416,14 +417,18 @@ int Create(struct supertype *st, char *mddev, int mdfd,
}
disk.raid_disk = disk.number;
if (disk.raid_disk < raiddisks)
disk.state = 6; /* active and in sync */
disk.state = (1<<MD_DISK_ACTIVE) |
(1<<MD_DISK_SYNC);
else
disk.state = 0;
if (dv->writemostly)
disk.state |= (1<<MD_DISK_WRITEMOSTLY);
if (dnum == insert_point ||
strcasecmp(dv->devname, "missing")==0) {
disk.major = 0;
disk.minor = 0;
disk.state = 1; /* faulty */
disk.state = (1<<MD_DISK_FAULTY);
} else {
fd = open(dv->devname, O_RDONLY|O_EXCL, 0);
if (fd < 0) {

3
Detail.c
View File

@ -216,6 +216,8 @@ int Detail(char *dev, int brief, int test)
for (d= 0; d < max_disks; d++) {
mdu_disk_info_t disk;
char *dv;
int wonly = disk.state & (1<<MD_DISK_WRITEMOSTLY);
disk.state &= ~(1<<MD_DISK_WRITEMOSTLY);
disk.number = d;
if (ioctl(fd, GET_DISK_INFO, &disk) < 0) {
if (d < array.raid_disks)
@ -244,6 +246,7 @@ int Detail(char *dev, int brief, int test)
if (disk.state & (1<<MD_DISK_ACTIVE)) printf(" active");
if (disk.state & (1<<MD_DISK_SYNC)) printf(" sync");
if (disk.state & (1<<MD_DISK_REMOVED)) printf(" removed");
if (wonly) printf(" writeonly");
if (disk.state == 0) printf(" spare");
if (disk.state == 0) {
if (is_26) {

4
Grow.c
View File

@ -192,7 +192,7 @@ int Grow_Add_device(char *devname, int fd, char *newdev)
return 0;
}
int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay)
int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay, int write_behind)
{
/*
* First check that array doesn't have a bitmap
@ -255,7 +255,7 @@ int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay)
continue;
if (st->ss->load_super(st, fd2, &super, NULL)==0) {
st->ss->add_internal_bitmap(super,
chunk, delay,
chunk, delay, write_behind,
array.size);
st->ss->write_bitmap(st, fd2, super);
}

2
Manage.c
View File

@ -266,6 +266,8 @@ int Manage_subdevs(char *devname, int fd,
disc.minor = minor(stb.st_rdev);
disc.number =j;
disc.state = 0;
if (dv->writemostly)
disc.state |= 1 << MD_DISK_WRITEMOSTLY;
st->ss->add_to_super(dsuper, &disc);
if (st->ss->write_init_super(st, dsuper, &disc, dv->devname))
return 1;

4
ReadMe.c
View File

@ -131,6 +131,8 @@ struct option long_options[] = {
{"metadata", 1, 0, 'e'}, /* superblock format */
{"bitmap", 1, 0, 'b'},
{"bitmap-chunk", 1, 0, 4},
{"write-behind", 2, 0, 5},
{"write-mostly",0, 0, 'W'},
/* For assemble */
{"uuid", 1, 0, 'u'},
@ -139,6 +141,7 @@ struct option long_options[] = {
{"scan", 0, 0, 's'},
{"force", 0, 0, 'f'},
{"update", 1, 0, 'U'},
/* Management */
{"add", 0, 0, 'a'},
{"remove", 0, 0, 'r'},
@ -232,6 +235,7 @@ char OptionHelp[] =
" --assume-clean : Assume the array is already in-sync. This is dangerous.\n"
" --bitmap-chunk= : chunksize of bitmap in bitmap file (Kilobytes)\n"
" --delay= -d : seconds between bitmap updates\n"
" --write-behind= : number of simultaneous write-behind requests to allow (requires bitmap)\n"
"\n"
" For assemble:\n"
" --bitmap= -b : File to find bitmap information in\n"

8
bitmap.c
View File

@ -215,6 +215,7 @@ int ExamineBitmap(char *filename, int brief, struct supertype *st)
bitmap_super_t *sb;
bitmap_info_t *info;
int rv = 1;
char buf[64];
info = bitmap_file_read(filename, brief, st);
if (!info)
@ -243,6 +244,11 @@ int ExamineBitmap(char *filename, int brief, struct supertype *st)
printf(" State : %s\n", bitmap_state(sb->state));
printf(" Chunksize : %s\n", human_chunksize(sb->chunksize));
printf(" Daemon : %ds flush period\n", sb->daemon_sleep);
if (sb->write_behind)
sprintf(buf, "Allow write behind, max %d", sb->write_behind);
else
sprintf(buf, "Normal");
printf(" Write Mode : %s\n", buf);
printf(" Sync Size : %llu%s\n", sb->sync_size/2,
human_size(sb->sync_size * 512));
if (brief)
@ -257,6 +263,7 @@ free_info:
int CreateBitmap(char *filename, int force, char uuid[16],
unsigned long chunksize, unsigned long daemon_sleep,
unsigned long write_behind,
unsigned long long array_size)
{
/*
@ -288,6 +295,7 @@ int CreateBitmap(char *filename, int force, char uuid[16],
memcpy(sb.uuid, uuid, 16);
sb.chunksize = chunksize;
sb.daemon_sleep = daemon_sleep;
sb.write_behind = write_behind;
sb.sync_size = array_size;
sb_cpu_to_le(&sb); /* convert to on-disk byte ordering */

12
bitmap.h
View File

@ -7,7 +7,7 @@
#define BITMAP_H 1
#define BITMAP_MAJOR 3
#define BITMAP_MINOR 38
#define BITMAP_MINOR 39
/*
* in-memory bitmap:
@ -43,6 +43,13 @@
* When we set a bit, or in the counter (to start a write), if the fields is
* 0, we first set the disk bit and set the counter to 1.
*
* If the counter is 0, the on-disk bit is clear and the stipe is clean
* Anything that dirties the stipe pushes the counter to 2 (at least)
* and sets the on-disk bit (lazily).
* If a periodic sweep find the counter at 2, it is decremented to 1.
* If the sweep find the counter at 1, the on-disk bit is cleared and the
* counter goes to zero.
*
* Also, we'll hijack the "map" pointer itself and use it as two 16 bit block
* counters as a fallback when "page" memory cannot be allocated:
*
@ -140,8 +147,9 @@ typedef struct bitmap_super_s {
__u32 state; /* 48 bitmap state information */
__u32 chunksize; /* 52 the bitmap chunk size in bytes */
__u32 daemon_sleep; /* 56 seconds between disk flushes */
__u32 write_behind; /* 60 number of outstanding write-behind writes */
__u8 pad[256 - 60]; /* set to zero */
__u8 pad[256 - 64]; /* set to zero */
} bitmap_super_t;
/* notes:

5
md_p.h
View File

@ -79,6 +79,11 @@
#define MD_DISK_SYNC 2 /* disk is in sync with the raid set */
#define MD_DISK_REMOVED 3 /* disk is in sync with the raid set */
#define MD_DISK_WRITEMOSTLY 9 /* disk is "write-mostly" is RAID1 config.
* read requests will only be sent here in
* dire need
*/
typedef struct mdp_device_descriptor_s {
__u32 number; /* 0 Device number in the entire set */
__u32 major; /* 1 Device major number */

33
mdadm.8
View File

@ -204,6 +204,18 @@ with
.B --verbose
gives an intermediate level of verbosity.
.TP
.BR -W ", " --write-mostly
subsequent devices lists in a
.BR --build ,
.BR --create ,
or
.B --add
command will be flagged as 'write-mostly'. This is valid for RAID1
only and means that the 'md' driver will avoid reading from these
devices if at all possible. This can be useful if mirroring over a
slow link.
.TP
.BR -b ", " --bitmap=
Give the name of a bitmap file to use with this array. Can be used
@ -215,6 +227,15 @@ exist).
Set the Chunksize of the bitmap. Each bit corresponds to that many
Kilobytes of storage. Default is 4.
.TP
.BR --write-behind=
Specify that write-behind mode should be enabled (valid for RAID1
only). If an argument is specified, it will set the maximum number
of outstanding writes allowed. The default value is 256.
A write-intent bitmap is required in order to use write-behind
mode, and write-behind is only attempted on drives marked as
.IR write-mostly .
.TP
.BR -f ", " --force
@ -1218,9 +1239,15 @@ For this to work, the kernel must support the necessary change.
Various types of growth may be added during 2.6 development, possibly
including restructuring a raid5 array to have more active devices.
Currently the only support available is to change the "size" attribute
for arrays with redundancy, and the raid-disks attribute of RAID1
arrays.
Currently the only support available is to
.IP \(bu 4
change the "size" attribute
for RAID1, RAID5 and RAID6.
.IP \(bu 4
change the "raid-disks" attribute of RAID1.
.IP \(bu 4
add a write-intent bitmap to a RAID1 array.
.PP
Normally when an array is build the "size" it taken from the smallest
of the drives. If all the small drives in an arrays are, one at a

45
mdadm.c
View File

@ -26,7 +26,7 @@
* Sydney, 2052
* Australia
*
* Additions for bitmap and async RAID options, Copyright (C) 2003-2004,
* Additions for bitmap and write-behind RAID options, Copyright (C) 2003-2004,
* Paul Clements, SteelEye Technology, Inc.
*/
@ -60,6 +60,7 @@ int main(int argc, char *argv[])
char devmode = 0;
int runstop = 0;
int readonly = 0;
int write_behind = 0;
int bitmap_fd = -1;
char *bitmap_file = NULL;
int bitmap_chunk = UnSet;
@ -89,6 +90,7 @@ int main(int argc, char *argv[])
char *pidfile = NULL;
int oneshot = 0;
struct supertype *ss = NULL;
int writemostly = 0;
int copies;
@ -214,6 +216,7 @@ int main(int argc, char *argv[])
}
dv->devname = optarg;
dv->disposition = devmode;
dv->writemostly = writemostly;
dv->next = NULL;
*devlistend = dv;
devlistend = &dv->next;
@ -262,6 +265,7 @@ int main(int argc, char *argv[])
}
dv->devname = optarg;
dv->disposition = devmode;
dv->writemostly = writemostly;
dv->next = NULL;
*devlistend = dv;
devlistend = &dv->next;
@ -306,6 +310,13 @@ int main(int argc, char *argv[])
max_disks = ss->max_devs;
continue;
case O(MANAGE,'W'):
case O(BUILD,'W'):
case O(CREATE,'W'):
/* set write-mostly for following devices */
writemostly = 1;
continue;
case O(GROW,'z'):
case O(CREATE,'z'): /* size */
if (size >= 0) {
@ -741,6 +752,19 @@ int main(int argc, char *argv[])
/* convert K to B, chunk of 0K means 512B */
bitmap_chunk = bitmap_chunk ? bitmap_chunk * 1024 : 512;
continue;
case O(BUILD, 5):
case O(CREATE, 5): /* write-behind mode */
write_behind = DEFAULT_MAX_WRITE_BEHIND;
if (optarg) {
write_behind = strtol(optarg, &c, 10);
if (write_behind < 0 || *c ||
write_behind > 16383) {
fprintf(stderr, Name ": Invalid value for maximum outstanding write-behind writes: %s.\n\tMust be between 0 and 16383.\n", optarg);
exit(2);
}
}
continue;
}
/* We have now processed all the valid options. Anything else is
* an error
@ -904,6 +928,12 @@ int main(int argc, char *argv[])
case BUILD:
if (bitmap_chunk == UnSet) bitmap_chunk = DEFAULT_BITMAP_CHUNK;
if (delay == 0) delay = DEFAULT_BITMAP_DELAY;
if (write_behind && !bitmap_file) {
fprintf(stderr, Name ": write-behind mode requires a bitmap.\n");
rv = 1;
break;
}
if (bitmap_file) {
if (strcmp(bitmap_file, "internal")==0) {
fprintf(stderr, Name ": 'internal' bitmaps not supported with --build\n");
@ -918,15 +948,20 @@ int main(int argc, char *argv[])
}
if (bitmap_fd < 0) {
bitmap_fd = CreateBitmap(bitmap_file, force, NULL,
bitmap_chunk, delay, size);
bitmap_chunk, delay, write_behind, size);
}
}
rv = Build(devlist->devname, mdfd, chunk, level, layout,
raiddisks, devlist->next, assume_clean,
bitmap_file, bitmap_chunk, delay);
bitmap_file, bitmap_chunk, write_behind, delay);
break;
case CREATE:
if (delay == 0) delay = DEFAULT_BITMAP_DELAY;
if (write_behind && !bitmap_file) {
fprintf(stderr, Name ": write-behind mode requires a bitmap.\n");
rv = 1;
break;
}
if (ss == NULL) {
for(i=0; !ss && superlist[i]; i++)
ss = superlist[i]->match_metadata_desc("default");
@ -939,7 +974,7 @@ int main(int argc, char *argv[])
rv = Create(ss, devlist->devname, mdfd, chunk, level, layout, size<0 ? 0 : size,
raiddisks, sparedisks,
devs_found-1, devlist->next, runstop, verbose, force,
bitmap_file, bitmap_chunk, delay);
bitmap_file, bitmap_chunk, write_behind, delay);
break;
case MISC:
@ -1078,7 +1113,7 @@ int main(int argc, char *argv[])
else if (bitmap_file) {
if (delay == 0) delay = DEFAULT_BITMAP_DELAY;
rv = Grow_addbitmap(devlist->devname, mdfd, bitmap_file,
bitmap_chunk, delay);
bitmap_chunk, delay, write_behind);
} else
fprintf(stderr, Name ": no changes to --grow\n");
break;

11
mdadm.h
View File

@ -64,6 +64,7 @@ char *strncpy(char *dest, const char *src, size_t n) __THROW;
#define DEFAULT_BITMAP_CHUNK 4096
#define DEFAULT_BITMAP_DELAY 5
#define DEFAULT_MAX_WRITE_BEHIND 256
#include "md_u.h"
#include "md_p.h"
@ -134,6 +135,7 @@ typedef struct mddev_dev_s {
char disposition; /* 'a' for add, 'r' for remove, 'f' for fail.
* Not set for names read from .config
*/
char writemostly;
struct mddev_dev_s *next;
} *mddev_dev_t;
@ -186,7 +188,7 @@ extern struct superswitch {
int (*load_super)(struct supertype *st, int fd, void **sbp, char *devname);
struct supertype * (*match_metadata_desc)(char *arg);
__u64 (*avail_size)(__u64 size);
int (*add_internal_bitmap)(void *sbv, int chunk, int delay, unsigned long long size);
int (*add_internal_bitmap)(void *sbv, int chunk, int delay, int write_behind, unsigned long long size);
void (*locate_bitmap)(struct supertype *st, int fd);
int (*write_bitmap)(struct supertype *st, int fd, void *sbv);
int major;
@ -223,7 +225,7 @@ extern int Manage_reconfig(char *devname, int fd, int layout);
extern int Manage_subdevs(char *devname, int fd,
mddev_dev_t devlist);
extern int Grow_Add_device(char *devname, int fd, char *newdev);
extern int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay);
extern int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay, int write_behind);
extern int Assemble(struct supertype *st, char *mddev, int mdfd,
@ -237,14 +239,14 @@ extern int Assemble(struct supertype *st, char *mddev, int mdfd,
extern int Build(char *mddev, int mdfd, int chunk, int level, int layout,
int raiddisks,
mddev_dev_t devlist, int assume_clean,
char *bitmap_file, int bitmap_chunk, int delay);
char *bitmap_file, int bitmap_chunk, int write_behind, int delay);
extern int Create(struct supertype *st, char *mddev, int mdfd,
int chunk, int level, int layout, unsigned long size, int raiddisks, int sparedisks,
int subdevs, mddev_dev_t devlist,
int runstop, int verbose, int force,
char *bitmap_file, int bitmap_chunk, int delay);
char *bitmap_file, int bitmap_chunk, int write_behind, int delay);
extern int Detail(char *dev, int brief, int test);
extern int Query(char *dev);
@ -259,6 +261,7 @@ extern int Kill(char *dev, int force);
extern int CreateBitmap(char *filename, int force, char uuid[16],
unsigned long chunksize, unsigned long daemon_sleep,
unsigned long write_behind,
unsigned long long array_size);
extern int ExamineBitmap(char *filename, int brief, struct supertype *st);

26
super0.c
View File

@ -148,15 +148,19 @@ static void examine_super0(void *sbv)
mdp_disk_t *dp;
char *dv;
char nb[5];
int wonly;
if (d>=0) dp = &sb->disks[d];
else dp = &sb->this_disk;
snprintf(nb, sizeof(nb), "%4d", d);
printf("%4s %5d %5d %5d %5d ", d < 0 ? "this" : nb,
dp->number, dp->major, dp->minor, dp->raid_disk);
wonly = dp->state & (1<<MD_DISK_WRITEMOSTLY);
dp->state &= ~(1<<MD_DISK_WRITEMOSTLY);
if (dp->state & (1<<MD_DISK_FAULTY)) printf(" faulty");
if (dp->state & (1<<MD_DISK_ACTIVE)) printf(" active");
if (dp->state & (1<<MD_DISK_SYNC)) printf(" sync");
if (dp->state & (1<<MD_DISK_REMOVED)) printf(" removed");
if (wonly) printf(" write-mostly");
if (dp->state == 0) printf(" spare");
if ((dv=map_dev(dp->major, dp->minor)))
printf(" %s", dv);
@ -312,8 +316,10 @@ static int update_super0(struct mdinfo *info, void *sbv, char *update, char *dev
}
if (strcmp(update, "assemble")==0) {
int d = info->disk.number;
int wonly = sb->disks[d].state & (1<<MD_DISK_WRITEMOSTLY);
sb->disks[d].state &= ~(1<<MD_DISK_WRITEMOSTLY);
if (sb->disks[d].state != info->disk.state) {
sb->disks[d].state = info->disk.state;
sb->disks[d].state = info->disk.state & wonly;
rv = 1;
}
}
@ -467,7 +473,7 @@ static int store_super0(struct supertype *st, int fd, void *sbv)
static int write_init_super0(struct supertype *st, void *sbv, mdu_disk_info_t *dinfo, char *devname)
{
mdp_super_t *sb = sbv;
int fd = open(devname, O_RDWR, O_EXCL);
int fd = open(devname, O_RDWR|O_EXCL);
int rv;
if (fd < 0) {
@ -485,6 +491,7 @@ static int write_init_super0(struct supertype *st, void *sbv, mdu_disk_info_t *d
if (sb->state & (1<<MD_SB_BITMAP_PRESENT)) {
int towrite, n;
char buf[4096];
write(fd, ((char*)sb)+MD_SB_BYTES, sizeof(bitmap_super_t));
towrite = 64*1024 - MD_SB_BYTES - sizeof(bitmap_super_t);
memset(buf, 0xff, sizeof(buf));
@ -498,6 +505,7 @@ static int write_init_super0(struct supertype *st, void *sbv, mdu_disk_info_t *d
else
break;
}
fsync(fd);
if (towrite)
rv = -2;
}
@ -661,7 +669,7 @@ static __u64 avail_size0(__u64 devsize)
return MD_NEW_SIZE_SECTORS(devsize);
}
static int add_internal_bitmap0(void *sbv, int chunk, int delay, unsigned long long size)
static int add_internal_bitmap0(void *sbv, int chunk, int delay, int write_behind, unsigned long long size)
{
/*
* The bitmap comes immediately after the superblock and must be 60K in size
@ -690,12 +698,13 @@ static int add_internal_bitmap0(void *sbv, int chunk, int delay, unsigned long l
sb->state |= (1<<MD_SB_BITMAP_PRESENT);
memset(bms, sizeof(*bms), 0);
bms->magic = __le32_to_cpu(BITMAP_MAGIC);
bms->version = __le32_to_cpu(BITMAP_MAJOR);
bms->magic = __cpu_to_le32(BITMAP_MAGIC);
bms->version = __cpu_to_le32(BITMAP_MAJOR);
uuid_from_super0((int*)bms->uuid, sb);
bms->chunksize = __le32_to_cpu(chunk);
bms->daemon_sleep = __le32_to_cpu(delay);
bms->sync_size = __le64_to_cpu(size);
bms->chunksize = __cpu_to_le32(chunk);
bms->daemon_sleep = __cpu_to_le32(delay);
bms->sync_size = __cpu_to_le64(size);
bms->write_behind = __cpu_to_le32(write_behind);
@ -776,6 +785,7 @@ int write_bitmap0(struct supertype *st, int fd, void *sbv)
else
break;
}
fsync(fd);
if (towrite)
rv = -2;

14
super1.c
View File

@ -64,7 +64,9 @@ struct mdp_superblock_1 {
__u32 dev_number; /* permanent identifier of this device - not role in raid */
__u32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */
__u8 device_uuid[16]; /* user-space setable, ignored by kernel */
__u8 pad2[64-56]; /* set to 0 when writing */
__u8 devflags; /* per-device flags. Only one defined...*/
#define WriteMostly1 1 /* mask for writemostly flag in above */
__u8 pad2[64-57]; /* set to 0 when writing */
/* array state information - 64 bytes */
__u64 utime; /* 40 bits second, 24 btes microseconds */
@ -153,6 +155,12 @@ static void examine_super1(void *sbv)
if ((i&3)==0 && i != 0) printf(":");
}
printf("\n");
if (sb->devflags) {
printf(" Flags :");
if (sb->devflags & WriteMostly1)
printf(" write-mostly");
printf("\n");
}
atime = __le64_to_cpu(sb->utime) & 0xFFFFFFFFFFULL;
printf(" Update Time : %.24s\n", ctime(&atime));
@ -429,7 +437,7 @@ static void add_to_super1(void *sbv, mdu_disk_info_t *dk)
{
struct mdp_superblock_1 *sb = sbv;
__u16 *rp = sb->dev_roles + dk->number;
if (dk->state == 6) /* active, sync */
if ((dk->state & 6) == 6) /* active, sync */
*rp = __cpu_to_le16(dk->raid_disk);
else if ((dk->state & ~2) == 0) /* active or idle -> spare */
*rp = 0xffff;
@ -517,6 +525,8 @@ static int write_init_super1(struct supertype *st, void *sbv, mdu_disk_info_t *d
}
sb->dev_number = __cpu_to_le32(dinfo->number);
if (dinfo->state & (1<<MD_DISK_WRITEMOSTLY))
sb->devflags |= WriteMostly1;
if ((rfd = open("/dev/urandom", O_RDONLY)) < 0 ||
read(rfd, sb->device_uuid, 16) != 16) {

15
tests/06wrmostly Normal file
View File

@ -0,0 +1,15 @@
set -e
# create a raid1 array with a wrmostly device
$mdadm -CR $md0 -l1 -n3 $dev0 $dev1 --write-mostly $dev2
sh tests/testdev $md0 1 $mdsize0 64
# unfortunately, we cannot measure if any read requests are going to $dev2
$mdadm -S $md0
$mdadm -CR $md0 -l1 -n3 --write-behind --bitmap=internal $dev0 $dev1 --write-mostly $dev2
sh tests/testdev $md0 1 $mdsize0 64
$mdadm -S $md0