Add write-behind support

[thirdparty/mdadm.git] / super1.c

diff --git a/super1.c b/super1.c
index 3c24f3481553dc1b953e9da860064f34cf9f17cd..f59eff06d6566473426e4e7b55805023d89c394f 100644 (file)
--- a/super1.c
+++ b/super1.c
@@ -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) {