md: collect bitmap-specific fields into one structure.

In preparation for making bitmap fields configurable via sysfs,
start tidying up by making a single structure to contain the
configuration fields.

Signed-off-by: NeilBrown <neilb@suse.de>

3 files changed, 63 insertions, 56 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index a5e5f2fbf963..c9270f2c9ecd 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1090,10 +1090,10 @@ void bitmap_daemon_work(mddev_t *mddev)
         /* Use a mutex to guard daemon_work against
          * bitmap_destroy.
          */
-        mutex_lock(&mddev->bitmap_mutex);
+        mutex_lock(&mddev->bitmap_info.mutex);
         bitmap = mddev->bitmap;
         if (bitmap == NULL) {
-                mutex_unlock(&mddev->bitmap_mutex);
+                mutex_unlock(&mddev->bitmap_info.mutex);
                 return;
         }
         if (time_before(jiffies, bitmap->daemon_lastrun + bitmap->daemon_sleep*HZ))
@@ -1211,7 +1211,7 @@ void bitmap_daemon_work(mddev_t *mddev)
  done:
         if (bitmap->allclean == 0)
                 bitmap->mddev->thread->timeout = bitmap->daemon_sleep * HZ;
-        mutex_unlock(&mddev->bitmap_mutex);
+        mutex_unlock(&mddev->bitmap_info.mutex);
 }
 
 static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
@@ -1591,9 +1591,9 @@ void bitmap_destroy(mddev_t *mddev)
         if (!bitmap) /* there was no bitmap */
                 return;
 
-        mutex_lock(&mddev->bitmap_mutex);
+        mutex_lock(&mddev->bitmap_info.mutex);
         mddev->bitmap = NULL; /* disconnect from the md device */
-        mutex_unlock(&mddev->bitmap_mutex);
+        mutex_unlock(&mddev->bitmap_info.mutex);
         if (mddev->thread)
                 mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
 
@@ -1610,16 +1610,16 @@ int bitmap_create(mddev_t *mddev)
         sector_t blocks = mddev->resync_max_sectors;
         unsigned long chunks;
         unsigned long pages;
-        struct file *file = mddev->bitmap_file;
+        struct file *file = mddev->bitmap_info.file;
         int err;
         sector_t start;
 
         BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
 
-        if (!file && !mddev->bitmap_offset) /* bitmap disabled, nothing to do */
+        if (!file && !mddev->bitmap_info.offset) /* bitmap disabled, nothing to do */
                 return 0;
 
-        BUG_ON(file && mddev->bitmap_offset);
+        BUG_ON(file && mddev->bitmap_info.offset);
 
         bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
         if (!bitmap)
@@ -1633,7 +1633,7 @@ int bitmap_create(mddev_t *mddev)
         bitmap->mddev = mddev;
 
         bitmap->file = file;
-        bitmap->offset = mddev->bitmap_offset;
+        bitmap->offset = mddev->bitmap_info.offset;
         if (file) {
                 get_file(file);
                 /* As future accesses to this file will use bmap,
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 569f25183db6..63da0a51852d 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -463,7 +463,7 @@ static mddev_t * mddev_find(dev_t unit)
 
         mutex_init(&new->open_mutex);
         mutex_init(&new->reconfig_mutex);
-        mutex_init(&new->bitmap_mutex);
+        mutex_init(&new->bitmap_info.mutex);
         INIT_LIST_HEAD(&new->disks);
         INIT_LIST_HEAD(&new->all_mddevs);
         init_timer(&new->safemode_timer);
@@ -850,7 +850,7 @@ struct super_type  {
  */
 int md_check_no_bitmap(mddev_t *mddev)
 {
-        if (!mddev->bitmap_file && !mddev->bitmap_offset)
+        if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
                 return 0;
         printk(KERN_ERR "%s: bitmaps are not supported for %s\n",
                 mdname(mddev), mddev->pers->name);
@@ -978,8 +978,8 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 mddev->raid_disks = sb->raid_disks;
                 mddev->dev_sectors = sb->size * 2;
                 mddev->events = ev1;
-                mddev->bitmap_offset = 0;
-                mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
+                mddev->bitmap_info.offset = 0;
+                mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
 
                 if (mddev->minor_version >= 91) {
                         mddev->reshape_position = sb->reshape_position;
@@ -1013,8 +1013,9 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 mddev->max_disks = MD_SB_DISKS;
 
                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
-                    mddev->bitmap_file == NULL)
-                        mddev->bitmap_offset = mddev->default_bitmap_offset;
+                    mddev->bitmap_info.file == NULL)
+                        mddev->bitmap_info.offset =
+                                mddev->bitmap_info.default_offset;
 
         } else if (mddev->pers == NULL) {
                 /* Insist on good event counter while assembling */
@@ -1131,7 +1132,7 @@ static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
         sb->layout = mddev->layout;
         sb->chunk_size = mddev->chunk_sectors << 9;
 
-        if (mddev->bitmap && mddev->bitmap_file == NULL)
+        if (mddev->bitmap && mddev->bitmap_info.file == NULL)
                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
 
         sb->disks[0].state = (1<<MD_DISK_REMOVED);
@@ -1209,7 +1210,7 @@ super_90_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
 {
         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
                 return 0; /* component must fit device */
-        if (rdev->mddev->bitmap_offset)
+        if (rdev->mddev->bitmap_info.offset)
                 return 0; /* can't move bitmap */
         rdev->sb_start = calc_dev_sboffset(rdev->bdev);
         if (!num_sectors || num_sectors > rdev->sb_start)
@@ -1388,8 +1389,8 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
                 mddev->dev_sectors = le64_to_cpu(sb->size);
                 mddev->events = ev1;
-                mddev->bitmap_offset = 0;
-                mddev->default_bitmap_offset = 1024 >> 9;
+                mddev->bitmap_info.offset = 0;
+                mddev->bitmap_info.default_offset = 1024 >> 9;
                 
                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
                 memcpy(mddev->uuid, sb->set_uuid, 16);
@@ -1397,8 +1398,9 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
                 mddev->max_disks =  (4096-256)/2;
 
                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
-                    mddev->bitmap_file == NULL )
-                        mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
+                    mddev->bitmap_info.file == NULL )
+                        mddev->bitmap_info.offset =
+                                (__s32)le32_to_cpu(sb->bitmap_offset);
 
                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
@@ -1492,8 +1494,8 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
         sb->level = cpu_to_le32(mddev->level);
         sb->layout = cpu_to_le32(mddev->layout);
 
-        if (mddev->bitmap && mddev->bitmap_file == NULL) {
-                sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
+        if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
+                sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
         }
 
@@ -1560,7 +1562,7 @@ super_1_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors)
                 max_sectors -= rdev->data_offset;
                 if (!num_sectors || num_sectors > max_sectors)
                         num_sectors = max_sectors;
-        } else if (rdev->mddev->bitmap_offset) {
+        } else if (rdev->mddev->bitmap_info.offset) {
                 /* minor version 0 with bitmap we can't move */
                 return 0;
         } else {
@@ -4507,12 +4509,12 @@ out:
                 printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
 
                 bitmap_destroy(mddev);
-                if (mddev->bitmap_file) {
-                        restore_bitmap_write_access(mddev->bitmap_file);
-                        fput(mddev->bitmap_file);
-                        mddev->bitmap_file = NULL;
+                if (mddev->bitmap_info.file) {
+                        restore_bitmap_write_access(mddev->bitmap_info.file);
+                        fput(mddev->bitmap_info.file);
+                        mddev->bitmap_info.file = NULL;
                 }
-                mddev->bitmap_offset = 0;
+                mddev->bitmap_info.offset = 0;
 
                 /* make sure all md_delayed_delete calls have finished */
                 flush_scheduled_work();
@@ -4553,6 +4555,8 @@ out:
                 mddev->degraded = 0;
                 mddev->barriers_work = 0;
                 mddev->safemode = 0;
+                mddev->bitmap_info.offset = 0;
+                mddev->bitmap_info.default_offset = 0;
                 kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
                 if (mddev->hold_active == UNTIL_STOP)
                         mddev->hold_active = 0;
@@ -4738,7 +4742,7 @@ static int get_array_info(mddev_t * mddev, void __user * arg)
         info.state         = 0;
         if (mddev->in_sync)
                 info.state = (1<<MD_SB_CLEAN);
-        if (mddev->bitmap && mddev->bitmap_offset)
+        if (mddev->bitmap && mddev->bitmap_info.offset)
                 info.state = (1<<MD_SB_BITMAP_PRESENT);
         info.active_disks  = insync;
         info.working_disks = working;
@@ -5096,23 +5100,23 @@ static int set_bitmap_file(mddev_t *mddev, int fd)
         if (fd >= 0) {
                 if (mddev->bitmap)
                         return -EEXIST; /* cannot add when bitmap is present */
-                mddev->bitmap_file = fget(fd);
+                mddev->bitmap_info.file = fget(fd);
 
-                if (mddev->bitmap_file == NULL) {
+                if (mddev->bitmap_info.file == NULL) {
                         printk(KERN_ERR "%s: error: failed to get bitmap file\n",
                                mdname(mddev));
                         return -EBADF;
                 }
 
-                err = deny_bitmap_write_access(mddev->bitmap_file);
+                err = deny_bitmap_write_access(mddev->bitmap_info.file);
                 if (err) {
                         printk(KERN_ERR "%s: error: bitmap file is already in use\n",
                                mdname(mddev));
-                        fput(mddev->bitmap_file);
-                        mddev->bitmap_file = NULL;
+                        fput(mddev->bitmap_info.file);
+                        mddev->bitmap_info.file = NULL;
                         return err;
                 }
-                mddev->bitmap_offset = 0; /* file overrides offset */
+                mddev->bitmap_info.offset = 0; /* file overrides offset */
         } else if (mddev->bitmap == NULL)
                 return -ENOENT; /* cannot remove what isn't there */
         err = 0;
@@ -5127,11 +5131,11 @@ static int set_bitmap_file(mddev_t *mddev, int fd)
                 mddev->pers->quiesce(mddev, 0);
         }
         if (fd < 0) {
-                if (mddev->bitmap_file) {
-                        restore_bitmap_write_access(mddev->bitmap_file);
-                        fput(mddev->bitmap_file);
+                if (mddev->bitmap_info.file) {
+                        restore_bitmap_write_access(mddev->bitmap_info.file);
+                        fput(mddev->bitmap_info.file);
                 }
-                mddev->bitmap_file = NULL;
+                mddev->bitmap_info.file = NULL;
         }
 
         return err;
@@ -5198,8 +5202,8 @@ static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
                 mddev->flags         = 0;
         set_bit(MD_CHANGE_DEVS, &mddev->flags);
 
-        mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
-        mddev->bitmap_offset = 0;
+        mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
+        mddev->bitmap_info.offset = 0;
 
         mddev->reshape_position = MaxSector;
 
@@ -5299,7 +5303,7 @@ static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
         int state = 0;
 
         /* calculate expected state,ignoring low bits */
-        if (mddev->bitmap && mddev->bitmap_offset)
+        if (mddev->bitmap && mddev->bitmap_info.offset)
                 state |= (1 << MD_SB_BITMAP_PRESENT);
 
         if (mddev->major_version != info->major_version ||
@@ -5358,9 +5362,10 @@ static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
                         /* add the bitmap */
                         if (mddev->bitmap)
                                 return -EEXIST;
-                        if (mddev->default_bitmap_offset == 0)
+                        if (mddev->bitmap_info.default_offset == 0)
                                 return -EINVAL;
-                        mddev->bitmap_offset = mddev->default_bitmap_offset;
+                        mddev->bitmap_info.offset =
+                                mddev->bitmap_info.default_offset;
                         mddev->pers->quiesce(mddev, 1);
                         rv = bitmap_create(mddev);
                         if (rv)
@@ -5375,7 +5380,7 @@ static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
                         mddev->pers->quiesce(mddev, 1);
                         bitmap_destroy(mddev);
                         mddev->pers->quiesce(mddev, 0);
-                        mddev->bitmap_offset = 0;
+                        mddev->bitmap_info.offset = 0;
                 }
         }
         md_update_sb(mddev, 1);
diff --git a/drivers/md/md.h b/drivers/md/md.h
index cb036868a9e9..50e62ef32e9d 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -280,16 +280,18 @@ struct mddev_s
         unsigned int                    max_write_behind; /* 0 = sync */
 
         struct bitmap                   *bitmap; /* the bitmap for the device */
-        struct file                     *bitmap_file; /* the bitmap file */
-        long                            bitmap_offset; /* offset from superblock of
-                                                        * start of bitmap. May be
-                                                        * negative, but not '0'
-                                                        */
-        long                            default_bitmap_offset; /* this is the offset to use when
-                                                                * hot-adding a bitmap.  It should
-                                                                * eventually be settable by sysfs.
-                                                                */
-        struct mutex                    bitmap_mutex;
+        struct {
+                struct file             *file; /* the bitmap file */
+                long                    offset; /* offset from superblock of
+                                                 * start of bitmap. May be
+                                                 * negative, but not '0'
+                                                 */
+                long                    default_offset; /* this is the offset to use when
+                                                         * hot-adding a bitmap.  It should
+                                                         * eventually be settable by sysfs.
+                                                         */
+                struct mutex            mutex;
+        } bitmap_info;
 
         struct list_head                all_mddevs;