mdadm: Add define for magic +9 in version string

To have it better understandable add definitions for that.
Definition is placed in md_common.h because it is corresponding to both
mdstat and sysfs implementations. Probably more shared properties will
be defined in the future.

The MD_EXTERNAL_PREFIX_LEN and MD_VERSION_BLOCKED_IDX are the same
but are defined for different purpose. One is specyfing size
of string but the second is specyfing index in the array.

Also, replaces magic "external" used in code.

No functional changes intended.

Signed-off-by: Mariusz Tkaczyk <mtkaczyk@kernel.org>

diff --git a/Assemble.c b/Assemble.c
index 7594e8f7877301f28b0545b52f95b15b9e9516a7..fa5ad07e48e16da3ffeca728ebbbfca32c3136c5 100644 (file)
--- a/Assemble.c
+++ b/Assemble.c
@@ -121,7 +121,7 @@ static int is_member_busy(char *metadata_version)
                        continue;
 
                /* Skip first char - it can be '/' or '-' */
-               if (strcmp(&ent->metadata_version[10], metadata_version + 1) == 0) {
+               if (strcmp(&ent->metadata_version[MD_VER_EXT_LEN + 1], metadata_version + 1) == 0) {
                        busy = 1;
                        break;
                }

diff --git a/Detail.c b/Detail.c
index 5d3d5c56f372094b87f243bbe7d41c714c267ce9..d9924b0365cc77828777a50aa566fdd753842735 100644 (file)
--- a/Detail.c
+++ b/Detail.c
@@ -684,10 +684,10 @@ int Detail(char *dev, struct context *c)
                                        de->d_name);
                                if (load_sys(path, vbuf, sizeof(vbuf)) < 0)
                                        continue;
-                               if (strncmp(vbuf, "external:", 9) ||
-                                   !is_subarray(vbuf + 9) ||
-                                   strncmp(vbuf + 10, sra->sys_name, nlen) ||
-                                   vbuf[10 + nlen] != '/')
+                               if (strncmp(vbuf, MD_VER_EXT, MD_VER_EXT_LEN) ||
+                                   !is_subarray(vbuf + MD_VER_EXT_LEN) ||
+                                   strncmp(vbuf + MD_VER_EXT_LEN + 1, sra->sys_name, nlen) ||
+                                   vbuf[MD_VER_EXT_LEN + 1 + nlen] != '/')
                                        continue;
                                devid = devnm2devid(de->d_name);
                                printf(" %s",

diff --git a/Grow.c b/Grow.c
index 8bcb7d4de9ba6f6b6d4c597552ef1effd1cc2429..f28abfee1e650182bb3a0fe251289a06ccc93f4f 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -697,7 +697,7 @@ static int check_idle(struct supertype *st)
                if (!is_container_member(e, container))
                        continue;
                /* frozen array is not idle*/
-               if (e->percent >= 0 || e->metadata_version[9] == '-') {
+               if (e->percent >= 0 || e->metadata_version[MD_VER_BLOCKED_IDX] == '-') {
                        is_idle = 0;
                        break;
                }

diff --git a/Manage.c b/Manage.c
index 18ebe67a0304a4d5d9f7e3b64beff508c7dc69f6..539c05e8096e7c8c2dfb1d2b5ddc22fe0306790f 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -49,12 +49,12 @@ int Manage_ro(char *devname, int fd, int readonly)
            mdi->array.major_version == -1 &&
            is_subarray(mdi->text_version)) {
                char vers[64];
-               strcpy(vers, "external:");
+               strcpy(vers, MD_VER_EXT);
                strcat(vers, mdi->text_version);
                if (readonly > 0) {
                        int rv;
                        /* We set readonly ourselves. */
-                       vers[9] = '-';
+                       vers[MD_VER_BLOCKED_IDX] = '-';
                        sysfs_set_str(mdi, NULL, "metadata_version", vers);
 
                        close_fd(&fd);
@@ -64,7 +64,7 @@ int Manage_ro(char *devname, int fd, int readonly)
                                pr_err("failed to set readonly for %s: %s\n",
                                        devname, strerror(errno));
 
-                               vers[9] = mdi->text_version[0];
+                               vers[MD_VER_BLOCKED_IDX] = mdi->text_version[0];
                                sysfs_set_str(mdi, NULL, "metadata_version", vers);
                                rv = 1;
                                goto out;
@@ -72,13 +72,13 @@ int Manage_ro(char *devname, int fd, int readonly)
                } else {
                        char *cp;
                        /* We cannot set read/write - must signal mdmon */
-                       vers[9] = '/';
+                       vers[MD_VER_BLOCKED_IDX] = '/';
                        sysfs_set_str(mdi, NULL, "metadata_version", vers);
 
-                       cp = strchr(vers+10, '/');
+                       cp = strchr(vers + MD_VER_BLOCKED_IDX + 1, '/');
                        if (cp)
                                *cp = 0;
-                       ping_monitor(vers+10);
+                       ping_monitor(vers + MD_VER_BLOCKED_IDX + 1);
                        if (mdi->array.level <= 0)
                                sysfs_set_str(mdi, NULL, "array_state", "active");
                }
@@ -279,7 +279,8 @@ int Manage_stop(char *devname, int fd, int verbose, int will_retry)
                mds = mdstat_read(0, 0);
                for (m = mds; m; m = m->next)
                        if (is_mdstat_ent_external(m) &&
-                           metadata_container_matches(m->metadata_version + 9, devnm)) {
+                           metadata_container_matches(m->metadata_version + MD_VER_EXT_LEN,
+                           devnm)) {
                                if (verbose >= 0)
                                        pr_err("Cannot stop container %s: member %s still active\n",
                                               devname, m->devnm);

diff --git a/md_common.h b/md_common.h
new file mode 100644 (file)
index 0000000..7e0c5d7
--- /dev/null
+++ b/md_common.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * md_common - constants shared between md driver abstractions.
+ */
+
+#ifndef MD_COMMON_H
+#define MD_COMMON_H
+
+/*
+ * Prefix used by the md driver version to mark an externally-managed array or
+ * container. The full form is:
+ *
+ *   "external:" [/-] containername [/subarray]
+ *
+ * The '/' or '-' separator distinguishes normal read-write arrays from those
+ * that mdmon must not reconfigure (read-only, reshaping, etc.).
+ */
+#define MD_EXT                  "external" /* The external keyword used in various contexts */
+
+#define MD_VER_EXT             "external:" /* The "external:" version const prefix */
+#define MD_VER_EXT_LEN (sizeof(MD_VER_EXT) - 1) /* Length of external prefix */
+
+/* Index of the character that blocks the version.
+ * It is the one after the prefix so the array index is MD_VER_EXT_LEN
+ */
+#define MD_VER_BLOCKED_IDX (MD_VER_EXT_LEN)
+
+#endif

diff --git a/mdmonitor.c b/mdmonitor.c
index d26d80dec5c3836ced6fd9bcdc3201b19f63ad37..b06fa46af73ee691ddd3724d90aa606bba320602 100644 (file)
--- a/mdmonitor.c
+++ b/mdmonitor.c
@@ -893,7 +893,8 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 
        if (is_mdstat_ent_subarray(mse)) {
                char *sl;
-               snprintf(st->parent_devnm, MD_NAME_MAX, "%s", mse->metadata_version + 10);
+               snprintf(st->parent_devnm, MD_NAME_MAX, "%s",
+                        mse->metadata_version + MD_VER_EXT_LEN + 1);
                sl = strchr(st->parent_devnm, '/');
                if (sl)
                        *sl = 0;
@@ -1006,7 +1007,7 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist)
                                char *sl;
 
                                snprintf(st->parent_devnm, MD_NAME_MAX, "%s",
-                                        mse->metadata_version + 10);
+                                        mse->metadata_version + MD_VER_EXT_LEN + 1);
                                sl = strchr(st->parent_devnm, '/');
                                if (sl)
                                        *sl = 0;
@@ -1307,8 +1308,8 @@ int Wait(char *dev)
                }
                if (!e || e->percent == RESYNC_NONE) {
                        if (e && is_mdstat_ent_external(e)) {
-                               if (is_subarray(&e->metadata_version[9]))
-                                       ping_monitor(&e->metadata_version[9]);
+                               if (is_subarray(&e->metadata_version[MD_VER_EXT_LEN]))
+                                       ping_monitor(&e->metadata_version[MD_VER_EXT_LEN]);
                                else
                                        ping_monitor(devnm);
                        }

diff --git a/mdstat.c b/mdstat.c
index 58376558b14c500d7f3c9ab9c610e07d19ae3b2d..f7f89ea8509d14e584fa7e859547233a61e9cb25 100644 (file)
--- a/mdstat.c
+++ b/mdstat.c
@@ -156,14 +156,14 @@ bool is_mdstat_ent_external(struct mdstat_ent *ent)
        if (!ent->metadata_version)
                return false;
 
-       if (strncmp(ent->metadata_version, "external:", 9) == 0)
+       if (strncmp(ent->metadata_version, MD_VER_EXT, MD_VER_EXT_LEN) == 0)
                return true;
        return false;
 }
 
 bool is_mdstat_ent_subarray(struct mdstat_ent *ent)
 {
-       if (is_mdstat_ent_external(ent) && is_subarray(ent->metadata_version + 9))
+       if (is_mdstat_ent_external(ent) && is_subarray(ent->metadata_version + MD_VER_EXT_LEN))
                return true;
        return false;
 }
@@ -171,7 +171,7 @@ bool is_mdstat_ent_subarray(struct mdstat_ent *ent)
 bool is_container_member(struct mdstat_ent *mdstat, char *container)
 {
        if (is_mdstat_ent_external(mdstat) &&
-           metadata_container_matches(mdstat->metadata_version + 9, container))
+           metadata_container_matches(mdstat->metadata_version + MD_VER_EXT_LEN, container))
                return true;
 
        return false;
@@ -509,9 +509,9 @@ struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container)
                if (!is_mdstat_ent_external(ent))
                        continue;
 
-               if (!metadata_container_matches(ent->metadata_version + 9, container))
+               if (!metadata_container_matches(ent->metadata_version + MD_VER_EXT_LEN, container))
                        continue;
-               if (!metadata_subdev_matches(ent->metadata_version + 9, subdev))
+               if (!metadata_subdev_matches(ent->metadata_version + MD_VER_EXT_LEN, subdev))
                        continue;
 
                break;

diff --git a/mdstat.h b/mdstat.h
index 76827c5c15dcf3829c23deaab2df142d5e0e1d5b..227a68b2aa9ec0d04a1bdd1ead69bc9423b6bd6f 100644 (file)
--- a/mdstat.h
+++ b/mdstat.h
@@ -7,6 +7,8 @@
 #include <stdbool.h>
 #include <string.h>
 
+#include "md_common.h"
+
 struct mdstat_ent {
        char devnm[32];
 
@@ -46,7 +48,8 @@ int is_subarray_active(char *subarray, char *container);
 
 static inline char *to_subarray(struct mdstat_ent *ent, char *container)
 {
-       return &ent->metadata_version[10+strlen(container)+1];
+       /* Skip: "external:" prefix, [/-] separator, container name, '/'. */
+       return &ent->metadata_version[MD_VER_EXT_LEN + 1 + strlen(container) + 1];
 }
 
 #endif

diff --git a/msg.c b/msg.c
index 313cb7c4c25c064755aa712b71d7fb7e8d1adff7..19e59186ec4353382d8d532c4d5ff172135ce8f4 100644 (file)
--- a/msg.c
+++ b/msg.c
@@ -252,7 +252,7 @@ int unblock_subarray(struct mdinfo *sra, const int unfreeze)
        int rc = 0;
 
        if (sra) {
-               sprintf(buf, "external:%s\n", sra->text_version);
+               sprintf(buf, MD_VER_EXT "%s\n", sra->text_version);
                buf[9] = '/';
        } else
                buf[9] = '-';
@@ -271,7 +271,7 @@ int block_subarray(struct mdinfo *sra)
        char buf[64];
        int rc = 0;
 
-       sprintf(buf, "external:%s\n", sra->text_version);
+       sprintf(buf, MD_VER_EXT "%s\n", sra->text_version);
        buf[9] = '-';
        if (sysfs_set_str(sra, NULL, "metadata_version", buf))
                rc = -1;

diff --git a/super-intel.c b/super-intel.c
index 5e44dc46428e5ba4e3439dd0bafc4b28d38054ac..dd268d23a80bb7e320c552a188df1ba0878eb71a 100644 (file)
--- a/super-intel.c
+++ b/super-intel.c
@@ -7083,8 +7083,9 @@ active_arrays_by_format(char *name, char* hba, struct md_list **devlist,
        int found;
 
        for (memb = mdstat ; memb ; memb = memb->next) {
-               if (is_mdstat_ent_external(memb) && !is_subarray(memb->metadata_version + 9) &&
-                   strcmp(&memb->metadata_version[9], name) == 0 && memb->members) {
+               if (is_mdstat_ent_external(memb) &&
+                   !is_subarray(memb->metadata_version + MD_VER_EXT_LEN) &&
+                   strcmp(&memb->metadata_version[MD_VER_EXT_LEN], name) == 0 && memb->members) {
                        struct dev_member *dev = memb->members;
                        int fd = -1;
 
@@ -13191,7 +13192,7 @@ static int set_bitmap_sysfs(struct mdinfo *info, unsigned long long chunksize,
         * related to the device's first lba (in opposition to the "internal" case
         * when this value is related to the beginning of the superblock).
         */
-       if (sysfs_set_str(info, NULL, "bitmap/metadata", "external")) {
+       if (sysfs_set_str(info, NULL, "bitmap/metadata", MD_EXT)) {
                dprintf("failed to set bitmap/metadata\n");
                return -1;
        }

diff --git a/sysfs.c b/sysfs.c
index 7589e944c8e690335c19fba5b1e1d3f4aa446ec0..96bfd5a7edf2f8cabf62a718432c988236bfd915 100644 (file)
--- a/sysfs.c
+++ b/sysfs.c
@@ -24,6 +24,7 @@
  */
 
 #include       "mdadm.h"
+#include       "md_common.h"
 #include       "dlink.h"
 #include       "xmalloc.h"
 
@@ -293,10 +294,10 @@ struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options)
                        sra->array.major_version =
                                sra->array.minor_version = -1;
                        strcpy(sra->text_version, "");
-               } else if (strncmp(buf, "external:", 9) == 0) {
+               } else if (strncmp(buf, MD_VER_EXT, MD_VER_EXT_LEN) == 0) {
                        sra->array.major_version = -1;
                        sra->array.minor_version = -2;
-                       strcpy(sra->text_version, buf+9);
+                       strcpy(sra->text_version, buf + MD_VER_EXT_LEN);
                        sra->text_version[sizeof(sra->text_version) - 1] = '\0';
                } else {
                        sscanf(buf, "%d.%d",
@@ -809,7 +810,7 @@ int sysfs_set_array(struct mdinfo *info)
            info->array.minor_version == -2) {
                char buf[SYSFS_MAX_BUF_SIZE];
 
-               strcat(strcpy(ver, "external:"), info->text_version);
+               strcat(strcpy(ver, MD_VER_EXT), info->text_version);
 
                /* meta version might already be set if we are setting
                 * new geometry for a reshape.  In that case we don't
@@ -819,8 +820,9 @@ int sysfs_set_array(struct mdinfo *info)
                 */
                if (sysfs_get_str(info, NULL, "metadata_version",
                                  buf, sizeof(buf)) > 0)
-                       if (strlen(buf) >= 9 && buf[9] == '-')
-                               ver[9] = '-';
+                       if (strlen(buf) >= MD_VER_BLOCKED_IDX &&
+                           buf[MD_VER_BLOCKED_IDX] == '-')
+                               ver[MD_VER_BLOCKED_IDX] = '-';
 
                if (sysfs_set_str(info, NULL, "metadata_version", ver) < 0) {
                        pr_err("This kernel does not support external metadata.\n");

diff --git a/util.c b/util.c
index 4e05a4cf9c0897de8d13714e4e10c56857870bac..3bd4829a07b00a850a47fb6b595575366061466d 100644 (file)
--- a/util.c
+++ b/util.c
@@ -23,6 +23,7 @@
  */
 
 #include       "mdadm.h"
+#include       "md_common.h"
 #include       "md_p.h"
 #include       "xmalloc.h"
 
@@ -1559,7 +1560,7 @@ int open_container(int fd)
                if (n <= 0 || (unsigned)n >= sizeof(buf))
                        continue;
                buf[n] = 0;
-               if (strncmp(buf, "external", 8) != 0 ||
+               if (strncmp(buf, MD_EXT, strlen(MD_EXT)) != 0 ||
                    n < 10 ||
                    buf[9] == '/')
                        continue;