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path: root/drivers/md/bitmap.c
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Diffstat (limited to 'drivers/md/bitmap.c')
-rw-r--r--drivers/md/bitmap.c183
1 files changed, 108 insertions, 75 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 41df4cda66e..2fba2bbe72d 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -270,19 +270,20 @@ static struct page *read_sb_page(mddev_t *mddev, long offset, unsigned long inde
if (!page)
return ERR_PTR(-ENOMEM);
- do {
- ITERATE_RDEV(mddev, rdev, tmp)
- if (rdev->in_sync && !rdev->faulty)
- goto found;
- return ERR_PTR(-EIO);
- found:
+ ITERATE_RDEV(mddev, rdev, tmp) {
+ if (! rdev->in_sync || rdev->faulty)
+ continue;
+
target = (rdev->sb_offset << 1) + offset + index * (PAGE_SIZE/512);
- } while (!sync_page_io(rdev->bdev, target, PAGE_SIZE, page, READ));
+ if (sync_page_io(rdev->bdev, target, PAGE_SIZE, page, READ)) {
+ page->index = index;
+ return page;
+ }
+ }
+ return ERR_PTR(-EIO);
- page->index = index;
- return page;
}
static int write_sb_page(mddev_t *mddev, long offset, struct page *page, int wait)
@@ -437,6 +438,7 @@ void bitmap_print_sb(struct bitmap *bitmap)
printk(KERN_DEBUG " daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
printk(KERN_DEBUG " sync size: %llu KB\n",
(unsigned long long)le64_to_cpu(sb->sync_size)/2);
+ printk(KERN_DEBUG "max write behind: %d\n", le32_to_cpu(sb->write_behind));
kunmap(bitmap->sb_page);
}
@@ -445,7 +447,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
{
char *reason = NULL;
bitmap_super_t *sb;
- unsigned long chunksize, daemon_sleep;
+ unsigned long chunksize, daemon_sleep, write_behind;
unsigned long bytes_read;
unsigned long long events;
int err = -EINVAL;
@@ -474,6 +476,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
chunksize = le32_to_cpu(sb->chunksize);
daemon_sleep = le32_to_cpu(sb->daemon_sleep);
+ write_behind = le32_to_cpu(sb->write_behind);
/* verify that the bitmap-specific fields are valid */
if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
@@ -485,7 +488,9 @@ static int bitmap_read_sb(struct bitmap *bitmap)
else if ((1 << ffz(~chunksize)) != chunksize)
reason = "bitmap chunksize not a power of 2";
else if (daemon_sleep < 1 || daemon_sleep > 15)
- reason = "daemon sleep period out of range";
+ reason = "daemon sleep period out of range (1-15s)";
+ else if (write_behind > COUNTER_MAX)
+ reason = "write-behind limit out of range (0 - 16383)";
if (reason) {
printk(KERN_INFO "%s: invalid bitmap file superblock: %s\n",
bmname(bitmap), reason);
@@ -518,8 +523,12 @@ success:
/* assign fields using values from superblock */
bitmap->chunksize = chunksize;
bitmap->daemon_sleep = daemon_sleep;
+ bitmap->daemon_lastrun = jiffies;
+ bitmap->max_write_behind = write_behind;
bitmap->flags |= sb->state;
bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
+ if (sb->state & BITMAP_STALE)
+ bitmap->events_cleared = bitmap->mddev->events;
err = 0;
out:
kunmap(bitmap->sb_page);
@@ -617,7 +626,7 @@ static void bitmap_file_unmap(struct bitmap *bitmap)
page_cache_release(sb_page);
}
-static void bitmap_stop_daemons(struct bitmap *bitmap);
+static void bitmap_stop_daemon(struct bitmap *bitmap);
/* dequeue the next item in a page list -- don't call from irq context */
static struct page_list *dequeue_page(struct bitmap *bitmap)
@@ -659,7 +668,7 @@ static void bitmap_file_put(struct bitmap *bitmap)
bitmap->file = NULL;
spin_unlock_irqrestore(&bitmap->lock, flags);
- bitmap_stop_daemons(bitmap);
+ bitmap_stop_daemon(bitmap);
drain_write_queues(bitmap);
@@ -818,7 +827,7 @@ int bitmap_unplug(struct bitmap *bitmap)
return 0;
}
-static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset);
+static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
/* * bitmap_init_from_disk -- called at bitmap_create time to initialize
* the in-memory bitmap from the on-disk bitmap -- also, sets up the
* memory mapping of the bitmap file
@@ -826,8 +835,11 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset);
* if there's no bitmap file, or if the bitmap file had been
* previously kicked from the array, we mark all the bits as
* 1's in order to cause a full resync.
+ *
+ * We ignore all bits for sectors that end earlier than 'start'.
+ * This is used when reading an out-of-date bitmap...
*/
-static int bitmap_init_from_disk(struct bitmap *bitmap)
+static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
{
unsigned long i, chunks, index, oldindex, bit;
struct page *page = NULL, *oldpage = NULL;
@@ -914,7 +926,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap)
* whole page and write it out
*/
memset(page_address(page) + offset, 0xff,
- PAGE_SIZE - offset);
+ PAGE_SIZE - offset);
ret = write_page(bitmap, page, 1);
if (ret) {
kunmap(page);
@@ -928,8 +940,11 @@ static int bitmap_init_from_disk(struct bitmap *bitmap)
}
if (test_bit(bit, page_address(page))) {
/* if the disk bit is set, set the memory bit */
- bitmap_set_memory_bits(bitmap, i << CHUNK_BLOCK_SHIFT(bitmap));
+ bitmap_set_memory_bits(bitmap, i << CHUNK_BLOCK_SHIFT(bitmap),
+ ((i+1) << (CHUNK_BLOCK_SHIFT(bitmap)) >= start)
+ );
bit_cnt++;
+ set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
}
}
@@ -1141,6 +1156,9 @@ static void bitmap_writeback_daemon(mddev_t *mddev)
err = -EINTR;
goto out;
}
+ if (bitmap == NULL)
+ /* about to be stopped. */
+ return;
PRINTK("%s: bitmap writeback daemon woke up...\n", bmname(bitmap));
/* wait on bitmap page writebacks */
@@ -1170,21 +1188,12 @@ static void bitmap_writeback_daemon(mddev_t *mddev)
}
}
-static int bitmap_start_daemon(struct bitmap *bitmap, mdk_thread_t **ptr,
+static mdk_thread_t *bitmap_start_daemon(struct bitmap *bitmap,
void (*func)(mddev_t *), char *name)
{
mdk_thread_t *daemon;
- unsigned long flags;
char namebuf[32];
- spin_lock_irqsave(&bitmap->lock, flags);
- *ptr = NULL;
-
- if (!bitmap->file) /* no need for daemon if there's no backing file */
- goto out_unlock;
-
- spin_unlock_irqrestore(&bitmap->lock, flags);
-
#ifdef INJECT_FATAL_FAULT_2
daemon = NULL;
#else
@@ -1194,47 +1203,32 @@ static int bitmap_start_daemon(struct bitmap *bitmap, mdk_thread_t **ptr,
if (!daemon) {
printk(KERN_ERR "%s: failed to start bitmap daemon\n",
bmname(bitmap));
- return -ECHILD;
+ return ERR_PTR(-ECHILD);
}
- spin_lock_irqsave(&bitmap->lock, flags);
- *ptr = daemon;
-
md_wakeup_thread(daemon); /* start it running */
PRINTK("%s: %s daemon (pid %d) started...\n",
bmname(bitmap), name, daemon->tsk->pid);
-out_unlock:
- spin_unlock_irqrestore(&bitmap->lock, flags);
- return 0;
-}
-static int bitmap_start_daemons(struct bitmap *bitmap)
-{
- int err = bitmap_start_daemon(bitmap, &bitmap->writeback_daemon,
- bitmap_writeback_daemon, "bitmap_wb");
- return err;
+ return daemon;
}
-static void bitmap_stop_daemon(struct bitmap *bitmap, mdk_thread_t **ptr)
+static void bitmap_stop_daemon(struct bitmap *bitmap)
{
- mdk_thread_t *daemon;
- unsigned long flags;
-
- spin_lock_irqsave(&bitmap->lock, flags);
- daemon = *ptr;
- *ptr = NULL;
- spin_unlock_irqrestore(&bitmap->lock, flags);
- if (daemon)
- md_unregister_thread(daemon); /* destroy the thread */
-}
+ /* the daemon can't stop itself... it'll just exit instead... */
+ if (bitmap->writeback_daemon && ! IS_ERR(bitmap->writeback_daemon) &&
+ current->pid != bitmap->writeback_daemon->tsk->pid) {
+ mdk_thread_t *daemon;
+ unsigned long flags;
-static void bitmap_stop_daemons(struct bitmap *bitmap)
-{
- /* the daemons can't stop themselves... they'll just exit instead... */
- if (bitmap->writeback_daemon &&
- current->pid != bitmap->writeback_daemon->tsk->pid)
- bitmap_stop_daemon(bitmap, &bitmap->writeback_daemon);
+ spin_lock_irqsave(&bitmap->lock, flags);
+ daemon = bitmap->writeback_daemon;
+ bitmap->writeback_daemon = NULL;
+ spin_unlock_irqrestore(&bitmap->lock, flags);
+ if (daemon && ! IS_ERR(daemon))
+ md_unregister_thread(daemon); /* destroy the thread */
+ }
}
static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
@@ -1274,9 +1268,16 @@ static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
}
}
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors)
+int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
{
if (!bitmap) return 0;
+
+ if (behind) {
+ atomic_inc(&bitmap->behind_writes);
+ PRINTK(KERN_DEBUG "inc write-behind count %d/%d\n",
+ atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
+ }
+
while (sectors) {
int blocks;
bitmap_counter_t *bmc;
@@ -1311,9 +1312,15 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
}
void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
- int success)
+ int success, int behind)
{
if (!bitmap) return;
+ if (behind) {
+ atomic_dec(&bitmap->behind_writes);
+ PRINTK(KERN_DEBUG "dec write-behind count %d/%d\n",
+ atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
+ }
+
while (sectors) {
int blocks;
unsigned long flags;
@@ -1424,7 +1431,7 @@ void bitmap_close_sync(struct bitmap *bitmap)
}
}
-static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset)
+static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
{
/* For each chunk covered by any of these sectors, set the
* counter to 1 and set resync_needed. They should all
@@ -1441,7 +1448,7 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset)
}
if (! *bmc) {
struct page *page;
- *bmc = 1 | NEEDED_MASK;
+ *bmc = 1 | (needed?NEEDED_MASK:0);
bitmap_count_page(bitmap, offset, 1);
page = filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap));
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
@@ -1476,17 +1483,14 @@ void bitmap_flush(mddev_t *mddev)
/*
* free memory that was allocated
*/
-void bitmap_destroy(mddev_t *mddev)
+static void bitmap_free(struct bitmap *bitmap)
{
unsigned long k, pages;
struct bitmap_page *bp;
- struct bitmap *bitmap = mddev->bitmap;
if (!bitmap) /* there was no bitmap */
return;
- mddev->bitmap = NULL; /* disconnect from the md device */
-
/* release the bitmap file and kill the daemon */
bitmap_file_put(bitmap);
@@ -1504,6 +1508,17 @@ void bitmap_destroy(mddev_t *mddev)
kfree(bp);
kfree(bitmap);
}
+void bitmap_destroy(mddev_t *mddev)
+{
+ struct bitmap *bitmap = mddev->bitmap;
+
+ if (!bitmap) /* there was no bitmap */
+ return;
+
+ mddev->bitmap = NULL; /* disconnect from the md device */
+
+ bitmap_free(bitmap);
+}
/*
* initialize the bitmap structure
@@ -1517,6 +1532,7 @@ int bitmap_create(mddev_t *mddev)
unsigned long pages;
struct file *file = mddev->bitmap_file;
int err;
+ sector_t start;
BUG_ON(sizeof(bitmap_super_t) != 256);
@@ -1533,15 +1549,15 @@ int bitmap_create(mddev_t *mddev)
spin_lock_init(&bitmap->lock);
bitmap->mddev = mddev;
- mddev->bitmap = bitmap;
spin_lock_init(&bitmap->write_lock);
INIT_LIST_HEAD(&bitmap->complete_pages);
init_waitqueue_head(&bitmap->write_wait);
bitmap->write_pool = mempool_create(WRITE_POOL_SIZE, write_pool_alloc,
write_pool_free, NULL);
+ err = -ENOMEM;
if (!bitmap->write_pool)
- return -ENOMEM;
+ goto error;
bitmap->file = file;
bitmap->offset = mddev->bitmap_offset;
@@ -1549,7 +1565,7 @@ int bitmap_create(mddev_t *mddev)
/* read superblock from bitmap file (this sets bitmap->chunksize) */
err = bitmap_read_sb(bitmap);
if (err)
- return err;
+ goto error;
bitmap->chunkshift = find_first_bit(&bitmap->chunksize,
sizeof(bitmap->chunksize));
@@ -1573,27 +1589,44 @@ int bitmap_create(mddev_t *mddev)
#else
bitmap->bp = kmalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL);
#endif
+ err = -ENOMEM;
if (!bitmap->bp)
- return -ENOMEM;
+ goto error;
memset(bitmap->bp, 0, pages * sizeof(*bitmap->bp));
bitmap->flags |= BITMAP_ACTIVE;
/* now that we have some pages available, initialize the in-memory
* bitmap from the on-disk bitmap */
- err = bitmap_init_from_disk(bitmap);
+ start = 0;
+ if (mddev->degraded == 0
+ || bitmap->events_cleared == mddev->events)
+ /* no need to keep dirty bits to optimise a re-add of a missing device */
+ start = mddev->recovery_cp;
+ err = bitmap_init_from_disk(bitmap, start);
if (err)
- return err;
+ goto error;
printk(KERN_INFO "created bitmap (%lu pages) for device %s\n",
pages, bmname(bitmap));
- /* kick off the bitmap daemons */
- err = bitmap_start_daemons(bitmap);
- if (err)
- return err;
+ mddev->bitmap = bitmap;
+
+ if (file)
+ /* kick off the bitmap writeback daemon */
+ bitmap->writeback_daemon =
+ bitmap_start_daemon(bitmap,
+ bitmap_writeback_daemon,
+ "bitmap_wb");
+
+ if (IS_ERR(bitmap->writeback_daemon))
+ return PTR_ERR(bitmap->writeback_daemon);
return bitmap_update_sb(bitmap);
+
+ error:
+ bitmap_free(bitmap);
+ return err;
}
/* the bitmap API -- for raid personalities */