drbd: Replaced the minor_table array by an idr

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 535d503886d89b21c637a2a7e63ea91eb797b6e4..783526ab7b20a91d60fc836e51d28bd48f8d2762 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -168,8 +168,8 @@ drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
 /* 4th incarnation of the disk layout. */
 #define DRBD_MD_MAGIC (DRBD_MAGIC+4)
 
-extern struct drbd_conf **minor_table;
 extern struct ratelimit_state drbd_ratelimit_state;
+extern struct idr minors;
 extern struct list_head drbd_tconns;
 
 /* on the wire */
@@ -1109,11 +1109,7 @@ struct drbd_conf {
 
 static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
 {
-       struct drbd_conf *mdev;
-
-       mdev = minor < minor_count ? minor_table[minor] : NULL;
-
-       return mdev;
+       return (struct drbd_conf *)idr_find(&minors, minor);
 }
 
 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index ec7d0d98657c9ab9dd1107c84d2ed874f321ddbe..6e190c0c9f6c3919939f0ea8963112ab3316c472 100644 (file)
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -74,7 +74,7 @@ MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
 MODULE_VERSION(REL_VERSION);
 MODULE_LICENSE("GPL");
-MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices ("
+MODULE_PARM_DESC(minor_count, "Approximate number of drbd devices ("
                 __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")");
 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
 
@@ -120,7 +120,7 @@ module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0
 /* in 2.6.x, our device mapping and config info contains our virtual gendisks
  * as member "struct gendisk *vdisk;"
  */
-struct drbd_conf **minor_table;
+struct idr minors;
 struct list_head drbd_tconns;  /* list of struct drbd_tconn */
 
 struct kmem_cache *drbd_request_cache;
@@ -2118,11 +2118,13 @@ void drbd_delete_device(unsigned int minor)
         * allocated from drbd_new_device
         * and actually free the mdev itself */
        drbd_free_mdev(mdev);
+       idr_remove(&minors, minor);
 }
 
 static void drbd_cleanup(void)
 {
        unsigned int i;
+       struct drbd_conf *mdev;
 
        unregister_reboot_notifier(&drbd_notifier);
 
@@ -2139,17 +2141,13 @@ static void drbd_cleanup(void)
 
        drbd_nl_cleanup();
 
-       if (minor_table) {
-               i = minor_count;
-               while (i--)
-                       drbd_delete_device(i);
-               drbd_destroy_mempools();
-       }
-
-       kfree(minor_table);
-
+       idr_for_each_entry(&minors, mdev, i)
+               drbd_delete_device(i);
+       drbd_destroy_mempools();
        unregister_blkdev(DRBD_MAJOR, "drbd");
 
+       idr_destroy(&minors);
+
        printk(KERN_INFO "drbd: module cleanup done.\n");
 }
 
@@ -2286,6 +2284,7 @@ enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor,
        struct gendisk *disk;
        struct request_queue *q;
        int vnr_got = vnr;
+       int minor_got = minor;
 
        mdev = minor_to_mdev(minor);
        if (mdev)
@@ -2361,13 +2360,20 @@ enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor,
        INIT_LIST_HEAD(&mdev->current_epoch->list);
        mdev->epochs = 1;
 
-       minor_table[minor] = mdev;
+       if (!idr_pre_get(&minors, GFP_KERNEL))
+               goto out_no_minor_idr;
+       if (idr_get_new(&minors, mdev, &minor_got))
+               goto out_no_minor_idr;
+       if (minor_got != minor) {
+               idr_remove(&minors, minor_got);
+               goto out_no_minor_idr;
+       }
        add_disk(disk);
 
        return NO_ERROR;
 
-/* out_whatever_else:
-       kfree(mdev->current_epoch); */
+out_no_minor_idr:
+       kfree(mdev->current_epoch);
 out_no_epoch:
        drbd_bm_cleanup(mdev);
 out_no_bitmap:
@@ -2406,7 +2412,7 @@ int __init drbd_init(void)
 
        if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
                printk(KERN_ERR
-                       "drbd: invalid minor_count (%d)\n", minor_count);
+                      "drbd: invalid minor_count (%d)\n", minor_count);
 #ifdef MODULE
                return -EINVAL;
 #else
@@ -2436,10 +2442,7 @@ int __init drbd_init(void)
        init_waitqueue_head(&drbd_pp_wait);
 
        drbd_proc = NULL; /* play safe for drbd_cleanup */
-       minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
-                               GFP_KERNEL);
-       if (!minor_table)
-               goto Enomem;
+       idr_init(&minors);
 
        err = drbd_create_mempools();
        if (err)
@@ -2460,7 +2463,6 @@ int __init drbd_init(void)
        printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
        printk(KERN_INFO "drbd: registered as block device major %d\n",
                DRBD_MAJOR);
-       printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
 
        return 0; /* Success! */
 

diff --git a/drivers/block/drbd/drbd_proc.c b/drivers/block/drbd/drbd_proc.c
index 4e53cb3d99e75b3a11e5649d450acd6ae52f6d79..36c9a6cecdc60843af66e6fa9eedec04346be7d0 100644 (file)
--- a/drivers/block/drbd/drbd_proc.c
+++ b/drivers/block/drbd/drbd_proc.c
@@ -194,7 +194,7 @@ static void resync_dump_detail(struct seq_file *seq, struct lc_element *e)
 
 static int drbd_seq_show(struct seq_file *seq, void *v)
 {
-       int i, hole = 0;
+       int i, prev_i = -1;
        const char *sn;
        struct drbd_conf *mdev;
 
@@ -227,16 +227,10 @@ static int drbd_seq_show(struct seq_file *seq, void *v)
         oos .. known out-of-sync kB
        */
 
-       for (i = 0; i < minor_count; i++) {
-               mdev = minor_to_mdev(i);
-               if (!mdev) {
-                       hole = 1;
-                       continue;
-               }
-               if (hole) {
-                       hole = 0;
+       idr_for_each_entry(&minors, mdev, i) {
+               if (prev_i != i - 1)
                        seq_printf(seq, "\n");
-               }
+               prev_i = i;
 
                sn = drbd_conn_str(mdev->state.conn);
 

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index fcdc2c1cc503ca79bf095edb8f1cdef8e1a40d15..e44bf3c25718403eab632a7495bf7fbdfe98a94b 100644 (file)
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -284,7 +284,7 @@ static void drbd_pp_free(struct drbd_conf *mdev, struct page *page, int is_net)
        atomic_t *a = is_net ? &mdev->pp_in_use_by_net : &mdev->pp_in_use;
        int i;
 
-       if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE)*minor_count)
+       if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count)
                i = page_chain_free(page);
        else {
                struct page *tmp;

diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 5cb5ffce097c010d3194f1b0df01fb62d87e8399..e459cb2076bd4bab3a4537d79826308a3b8b337c 100644 (file)
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1349,10 +1349,7 @@ static int _drbd_pause_after(struct drbd_conf *mdev)
        struct drbd_conf *odev;
        int i, rv = 0;
 
-       for (i = 0; i < minor_count; i++) {
-               odev = minor_to_mdev(i);
-               if (!odev)
-                       continue;
+       idr_for_each_entry(&minors, odev, i) {
                if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
                        continue;
                if (!_drbd_may_sync_now(odev))
@@ -1374,10 +1371,7 @@ static int _drbd_resume_next(struct drbd_conf *mdev)
        struct drbd_conf *odev;
        int i, rv = 0;
 
-       for (i = 0; i < minor_count; i++) {
-               odev = minor_to_mdev(i);
-               if (!odev)
-                       continue;
+       idr_for_each_entry(&minors, odev, i) {
                if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS)
                        continue;
                if (odev->state.aftr_isp) {