[PATCH 16/16] drbd: Replaced the minor_table array by an idr
From: Philipp Reisner
Date: Wed Aug 31 2011 - 11:12:31 EST
Signed-off-by: Philipp Reisner <philipp.reisner@xxxxxxxxxx>
Signed-off-by: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
---
drivers/block/drbd/drbd_int.h | 8 +-----
drivers/block/drbd/drbd_main.c | 42 ++++++++++++++++++-----------------
drivers/block/drbd/drbd_proc.c | 14 +++--------
drivers/block/drbd/drbd_receiver.c | 2 +-
drivers/block/drbd/drbd_worker.c | 10 +------
5 files changed, 31 insertions(+), 45 deletions(-)
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 5fb5bd0..e3f542c 100644
--- 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 1188fca..0a2575c 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -74,7 +74,7 @@ MODULE_AUTHOR("Philipp Reisner <phil@xxxxxxxxxx>, "
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:
@@ -2407,7 +2413,7 @@ 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
@@ -2437,10 +2443,7 @@ 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)
@@ -2461,7 +2464,6 @@ 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 4e53cb3..36c9a6c 100644
--- 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 e607503..620f27f 100644
--- 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 5cb5ffc..e459cb2 100644
--- 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) {
--
1.7.4.1
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