1 files changed, 74 insertions, 35 deletions

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 8edd6435414d..3edb3477f987 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
- * Copyright (C) 2004 - 2005 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved.
  *
  * This file is released under the GPL.
  */
@@ -19,6 +19,7 @@
 
 #include <asm/uaccess.h>
 
+#define DM_MSG_PREFIX "ioctl"
 #define DM_DRIVER_EMAIL "dm-devel@redhat.com"
 
 /*-----------------------------------------------------------------
@@ -48,7 +49,7 @@ struct vers_iter {
 static struct list_head _name_buckets[NUM_BUCKETS];
 static struct list_head _uuid_buckets[NUM_BUCKETS];
 
-static void dm_hash_remove_all(void);
+static void dm_hash_remove_all(int keep_open_devices);
 
 /*
  * Guards access to both hash tables.
@@ -73,7 +74,7 @@ static int dm_hash_init(void)
 
 static void dm_hash_exit(void)
 {
-        dm_hash_remove_all();
+        dm_hash_remove_all(0);
         devfs_remove(DM_DIR);
 }
 
@@ -102,8 +103,10 @@ static struct hash_cell *__get_name_cell(const char *str)
         unsigned int h = hash_str(str);
 
         list_for_each_entry (hc, _name_buckets + h, name_list)
-                if (!strcmp(hc->name, str))
+                if (!strcmp(hc->name, str)) {
+                        dm_get(hc->md);
                         return hc;
+                }
 
         return NULL;
 }
@@ -114,8 +117,10 @@ static struct hash_cell *__get_uuid_cell(const char *str)
         unsigned int h = hash_str(str);
 
         list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
-                if (!strcmp(hc->uuid, str))
+                if (!strcmp(hc->uuid, str)) {
+                        dm_get(hc->md);
                         return hc;
+                }
 
         return NULL;
 }
@@ -191,7 +196,7 @@ static int unregister_with_devfs(struct hash_cell *hc)
  */
 static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
 {
-        struct hash_cell *cell;
+        struct hash_cell *cell, *hc;
 
         /*
          * Allocate the new cells.
@@ -204,14 +209,19 @@ static int dm_hash_insert(const char *name, const char *uuid, struct mapped_devi
          * Insert the cell into both hash tables.
          */
         down_write(&_hash_lock);
-        if (__get_name_cell(name))
+        hc = __get_name_cell(name);
+        if (hc) {
+                dm_put(hc->md);
                 goto bad;
+        }
 
         list_add(&cell->name_list, _name_buckets + hash_str(name));
 
         if (uuid) {
-                if (__get_uuid_cell(uuid)) {
+                hc = __get_uuid_cell(uuid);
+                if (hc) {
                         list_del(&cell->name_list);
+                        dm_put(hc->md);
                         goto bad;
                 }
                 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
@@ -251,19 +261,41 @@ static void __hash_remove(struct hash_cell *hc)
         free_cell(hc);
 }
 
-static void dm_hash_remove_all(void)
+static void dm_hash_remove_all(int keep_open_devices)
 {
-        int i;
+        int i, dev_skipped, dev_removed;
         struct hash_cell *hc;
         struct list_head *tmp, *n;
 
         down_write(&_hash_lock);
+
+retry:
+        dev_skipped = dev_removed = 0;
         for (i = 0; i < NUM_BUCKETS; i++) {
                 list_for_each_safe (tmp, n, _name_buckets + i) {
                         hc = list_entry(tmp, struct hash_cell, name_list);
+
+                        if (keep_open_devices &&
+                            dm_lock_for_deletion(hc->md)) {
+                                dev_skipped++;
+                                continue;
+                        }
                         __hash_remove(hc);
+                        dev_removed = 1;
                 }
         }
+
+        /*
+         * Some mapped devices may be using other mapped devices, so if any
+         * still exist, repeat until we make no further progress.
+         */
+        if (dev_skipped) {
+                if (dev_removed)
+                        goto retry;
+
+                DMWARN("remove_all left %d open device(s)", dev_skipped);
+        }
+
         up_write(&_hash_lock);
 }
 
@@ -289,6 +321,7 @@ static int dm_hash_rename(const char *old, const char *new)
         if (hc) {
                 DMWARN("asked to rename to an already existing name %s -> %s",
                        old, new);
+                dm_put(hc->md);
                 up_write(&_hash_lock);
                 kfree(new_name);
                 return -EBUSY;
@@ -328,6 +361,7 @@ static int dm_hash_rename(const char *old, const char *new)
                 dm_table_put(table);
         }
 
+        dm_put(hc->md);
         up_write(&_hash_lock);
         kfree(old_name);
         return 0;
@@ -344,7 +378,7 @@ typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
 
 static int remove_all(struct dm_ioctl *param, size_t param_size)
 {
-        dm_hash_remove_all();
+        dm_hash_remove_all(1);
         param->data_size = 0;
         return 0;
 }
@@ -524,7 +558,6 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
 {
         struct gendisk *disk = dm_disk(md);
         struct dm_table *table;
-        struct block_device *bdev;
 
         param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
                           DM_ACTIVE_PRESENT_FLAG);
@@ -534,20 +567,12 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
 
         param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
 
-        if (!(param->flags & DM_SKIP_BDGET_FLAG)) {
-                bdev = bdget_disk(disk, 0);
-                if (!bdev)
-                        return -ENXIO;
-
-                /*
-                 * Yes, this will be out of date by the time it gets back
-                 * to userland, but it is still very useful for
-                 * debugging.
-                 */
-                param->open_count = bdev->bd_openers;
-                bdput(bdev);
-        } else
-                param->open_count = -1;
+        /*
+         * Yes, this will be out of date by the time it gets back
+         * to userland, but it is still very useful for
+         * debugging.
+         */
+        param->open_count = dm_open_count(md);
 
         if (disk->policy)
                 param->flags |= DM_READONLY_FLAG;
@@ -567,7 +592,7 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
 
 static int dev_create(struct dm_ioctl *param, size_t param_size)
 {
-        int r;
+        int r, m = DM_ANY_MINOR;
         struct mapped_device *md;
 
         r = check_name(param->name);
@@ -575,10 +600,9 @@ static int dev_create(struct dm_ioctl *param, size_t param_size)
                 return r;
 
         if (param->flags & DM_PERSISTENT_DEV_FLAG)
-                r = dm_create_with_minor(MINOR(huge_decode_dev(param->dev)), &md);
-        else
-                r = dm_create(&md);
+                m = MINOR(huge_decode_dev(param->dev));
 
+        r = dm_create(m, &md);
         if (r)
                 return r;
 
@@ -611,10 +635,8 @@ static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
                 return __get_name_cell(param->name);
 
         md = dm_get_md(huge_decode_dev(param->dev));
-        if (md) {
+        if (md)
                 mdptr = dm_get_mdptr(md);
-                dm_put(md);
-        }
 
         return mdptr;
 }
@@ -628,7 +650,6 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
         hc = __find_device_hash_cell(param);
         if (hc) {
                 md = hc->md;
-                dm_get(md);
 
                 /*
                  * Sneakily write in both the name and the uuid
@@ -653,6 +674,8 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
 static int dev_remove(struct dm_ioctl *param, size_t param_size)
 {
         struct hash_cell *hc;
+        struct mapped_device *md;
+        int r;
 
         down_write(&_hash_lock);
         hc = __find_device_hash_cell(param);
@@ -663,8 +686,22 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size)
                 return -ENXIO;
         }
 
+        md = hc->md;
+
+        /*
+         * Ensure the device is not open and nothing further can open it.
+         */
+        r = dm_lock_for_deletion(md);
+        if (r) {
+                DMWARN("unable to remove open device %s", hc->name);
+                up_write(&_hash_lock);
+                dm_put(md);
+                return r;
+        }
+
         __hash_remove(hc);
         up_write(&_hash_lock);
+        dm_put(md);
         param->data_size = 0;
         return 0;
 }
@@ -790,7 +827,6 @@ static int do_resume(struct dm_ioctl *param)
         }
 
         md = hc->md;
-        dm_get(md);
 
         new_map = hc->new_map;
         hc->new_map = NULL;
@@ -1078,6 +1114,7 @@ static int table_clear(struct dm_ioctl *param, size_t param_size)
 {
         int r;
         struct hash_cell *hc;
+        struct mapped_device *md;
 
         down_write(&_hash_lock);
 
@@ -1096,7 +1133,9 @@ static int table_clear(struct dm_ioctl *param, size_t param_size)
         param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
 
         r = __dev_status(hc->md, param);
+        md = hc->md;
         up_write(&_hash_lock);
+        dm_put(md);
         return r;
 }