[PATCH 007 of 7] md: Change bitmap_unplug and others to void functions.
From: NeilBrown
Date: Sun May 20 2007 - 21:35:57 EST
bitmap_unplug only ever returns 0, so it may as well be void.
Two callers try to print a message if it returns non-zero, but
that message is already printed by bitmap_file_kick.
write_page returns an error which is not consistently checked. It
always causes BITMAP_WRITE_ERROR to be set on an error, and that can
more conveniently be checked.
When the return of write_page is checked, an error causes bitmap_file_kick
to be called - so move that call into write_page - and protect against
recursive calls into bitmap_file_kick.
bitmap_update_sb returns an error that is never checked.
So make these 'void' and be consistent about checking the bit.
Signed-off-by: Neil Brown <neilb@xxxxxxx>
### Diffstat output
./drivers/md/bitmap.c | 144 +++++++++++++++++++++---------------------
./drivers/md/md.c | 3
./drivers/md/raid1.c | 3
./drivers/md/raid10.c | 3
./include/linux/raid/bitmap.h | 6 -
5 files changed, 80 insertions(+), 79 deletions(-)
diff .prev/drivers/md/bitmap.c ./drivers/md/bitmap.c
--- .prev/drivers/md/bitmap.c 2007-05-21 11:18:22.000000000 +1000
+++ ./drivers/md/bitmap.c 2007-05-21 11:18:23.000000000 +1000
@@ -305,10 +305,11 @@ static int write_sb_page(struct bitmap *
return 0;
}
+static void bitmap_file_kick(struct bitmap *bitmap);
/*
* write out a page to a file
*/
-static int write_page(struct bitmap *bitmap, struct page *page, int wait)
+static void write_page(struct bitmap *bitmap, struct page *page, int wait)
{
struct buffer_head *bh;
@@ -316,27 +317,26 @@ static int write_page(struct bitmap *bit
switch (write_sb_page(bitmap, page, wait)) {
case -EINVAL:
bitmap->flags |= BITMAP_WRITE_ERROR;
- return -EIO;
}
- return 0;
- }
+ } else {
- bh = page_buffers(page);
+ bh = page_buffers(page);
- while (bh && bh->b_blocknr) {
- atomic_inc(&bitmap->pending_writes);
- set_buffer_locked(bh);
- set_buffer_mapped(bh);
- submit_bh(WRITE, bh);
- bh = bh->b_this_page;
- }
+ while (bh && bh->b_blocknr) {
+ atomic_inc(&bitmap->pending_writes);
+ set_buffer_locked(bh);
+ set_buffer_mapped(bh);
+ submit_bh(WRITE, bh);
+ bh = bh->b_this_page;
+ }
- if (wait) {
- wait_event(bitmap->write_wait,
- atomic_read(&bitmap->pending_writes)==0);
- return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0;
+ if (wait) {
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ }
}
- return 0;
+ if (bitmap->flags & BITMAP_WRITE_ERROR)
+ bitmap_file_kick(bitmap);
}
static void end_bitmap_write(struct buffer_head *bh, int uptodate)
@@ -456,17 +456,17 @@ out:
*/
/* update the event counter and sync the superblock to disk */
-int bitmap_update_sb(struct bitmap *bitmap)
+void bitmap_update_sb(struct bitmap *bitmap)
{
bitmap_super_t *sb;
unsigned long flags;
if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
- return 0;
+ return;
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->sb_page) { /* no superblock */
spin_unlock_irqrestore(&bitmap->lock, flags);
- return 0;
+ return;
}
spin_unlock_irqrestore(&bitmap->lock, flags);
sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
@@ -474,7 +474,7 @@ int bitmap_update_sb(struct bitmap *bitm
if (!bitmap->mddev->degraded)
sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
kunmap_atomic(sb, KM_USER0);
- return write_page(bitmap, bitmap->sb_page, 1);
+ write_page(bitmap, bitmap->sb_page, 1);
}
/* print out the bitmap file superblock */
@@ -603,20 +603,22 @@ enum bitmap_mask_op {
MASK_UNSET
};
-/* record the state of the bitmap in the superblock */
-static void bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
- enum bitmap_mask_op op)
+/* record the state of the bitmap in the superblock. Return the old value */
+static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
+ enum bitmap_mask_op op)
{
bitmap_super_t *sb;
unsigned long flags;
+ int old;
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->sb_page) { /* can't set the state */
spin_unlock_irqrestore(&bitmap->lock, flags);
- return;
+ return 0;
}
spin_unlock_irqrestore(&bitmap->lock, flags);
sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+ old = le32_to_cpu(sb->state) & bits;
switch (op) {
case MASK_SET: sb->state |= cpu_to_le32(bits);
break;
@@ -625,6 +627,7 @@ static void bitmap_mask_state(struct bit
default: BUG();
}
kunmap_atomic(sb, KM_USER0);
+ return old;
}
/*
@@ -718,18 +721,23 @@ static void bitmap_file_kick(struct bitm
{
char *path, *ptr = NULL;
- bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET);
- bitmap_update_sb(bitmap);
-
- if (bitmap->file) {
- path = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (path)
- ptr = file_path(bitmap->file, path, PAGE_SIZE);
-
- printk(KERN_ALERT "%s: kicking failed bitmap file %s from array!\n",
- bmname(bitmap), ptr ? ptr : "");
+ if (bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET) == 0) {
+ bitmap_update_sb(bitmap);
- kfree(path);
+ if (bitmap->file) {
+ path = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (path)
+ ptr = file_path(bitmap->file, path, PAGE_SIZE);
+
+ printk(KERN_ALERT
+ "%s: kicking failed bitmap file %s from array!\n",
+ bmname(bitmap), ptr ? ptr : "");
+
+ kfree(path);
+ } else
+ printk(KERN_ALERT
+ "%s: disabling internal bitmap due to errors\n",
+ bmname(bitmap));
}
bitmap_file_put(bitmap);
@@ -800,16 +808,15 @@ static void bitmap_file_set_bit(struct b
/* this gets called when the md device is ready to unplug its underlying
* (slave) device queues -- before we let any writes go down, we need to
* sync the dirty pages of the bitmap file to disk */
-int bitmap_unplug(struct bitmap *bitmap)
+void bitmap_unplug(struct bitmap *bitmap)
{
unsigned long i, flags;
int dirty, need_write;
struct page *page;
int wait = 0;
- int err;
if (!bitmap)
- return 0;
+ return;
/* look at each page to see if there are any set bits that need to be
* flushed out to disk */
@@ -817,7 +824,7 @@ int bitmap_unplug(struct bitmap *bitmap)
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->filemap) {
spin_unlock_irqrestore(&bitmap->lock, flags);
- return 0;
+ return;
}
page = bitmap->filemap[i];
dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
@@ -829,7 +836,7 @@ int bitmap_unplug(struct bitmap *bitmap)
spin_unlock_irqrestore(&bitmap->lock, flags);
if (dirty | need_write)
- err = write_page(bitmap, page, 0);
+ write_page(bitmap, page, 0);
}
if (wait) { /* if any writes were performed, we need to wait on them */
if (bitmap->file)
@@ -840,7 +847,6 @@ int bitmap_unplug(struct bitmap *bitmap)
}
if (bitmap->flags & BITMAP_WRITE_ERROR)
bitmap_file_kick(bitmap);
- return 0;
}
static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
@@ -889,21 +895,21 @@ static int bitmap_init_from_disk(struct
bmname(bitmap),
(unsigned long) i_size_read(file->f_mapping->host),
bytes + sizeof(bitmap_super_t));
- goto out;
+ goto err;
}
ret = -ENOMEM;
bitmap->filemap = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
if (!bitmap->filemap)
- goto out;
+ goto err;
/* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
bitmap->filemap_attr = kzalloc(
roundup( DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
GFP_KERNEL);
if (!bitmap->filemap_attr)
- goto out;
+ goto err;
oldindex = ~0L;
@@ -936,7 +942,7 @@ static int bitmap_init_from_disk(struct
}
if (IS_ERR(page)) { /* read error */
ret = PTR_ERR(page);
- goto out;
+ goto err;
}
oldindex = index;
@@ -951,11 +957,13 @@ static int bitmap_init_from_disk(struct
memset(paddr + offset, 0xff,
PAGE_SIZE - offset);
kunmap_atomic(paddr, KM_USER0);
- ret = write_page(bitmap, page, 1);
- if (ret) {
+ write_page(bitmap, page, 1);
+
+ ret = -EIO;
+ if (bitmap->flags & BITMAP_WRITE_ERROR) {
/* release, page not in filemap yet */
put_page(page);
- goto out;
+ goto err;
}
}
@@ -987,11 +995,15 @@ static int bitmap_init_from_disk(struct
md_wakeup_thread(bitmap->mddev->thread);
}
-out:
printk(KERN_INFO "%s: bitmap initialized from disk: "
- "read %lu/%lu pages, set %lu bits, status: %d\n",
- bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt, ret);
+ "read %lu/%lu pages, set %lu bits\n",
+ bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt);
+
+ return 0;
+ err:
+ printk(KERN_INFO "%s: bitmap initialisation failed: %d\n",
+ bmname(bitmap), ret);
return ret;
}
@@ -1028,19 +1040,18 @@ static bitmap_counter_t *bitmap_get_coun
* out to disk
*/
-int bitmap_daemon_work(struct bitmap *bitmap)
+void bitmap_daemon_work(struct bitmap *bitmap)
{
unsigned long j;
unsigned long flags;
struct page *page = NULL, *lastpage = NULL;
- int err = 0;
int blocks;
void *paddr;
if (bitmap == NULL)
- return 0;
+ return;
if (time_before(jiffies, bitmap->daemon_lastrun + bitmap->daemon_sleep*HZ))
- return 0;
+ return;
bitmap->daemon_lastrun = jiffies;
for (j = 0; j < bitmap->chunks; j++) {
@@ -1063,14 +1074,8 @@ int bitmap_daemon_work(struct bitmap *bi
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- if (need_write) {
- switch (write_page(bitmap, page, 0)) {
- case 0:
- break;
- default:
- bitmap_file_kick(bitmap);
- }
- }
+ if (need_write)
+ write_page(bitmap, page, 0);
continue;
}
@@ -1079,13 +1084,11 @@ int bitmap_daemon_work(struct bitmap *bi
if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- err = write_page(bitmap, lastpage, 0);
+ write_page(bitmap, lastpage, 0);
} else {
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
}
- if (err)
- bitmap_file_kick(bitmap);
} else
spin_unlock_irqrestore(&bitmap->lock, flags);
lastpage = page;
@@ -1128,14 +1131,13 @@ int bitmap_daemon_work(struct bitmap *bi
if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- err = write_page(bitmap, lastpage, 0);
+ write_page(bitmap, lastpage, 0);
} else {
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
}
}
- return err;
}
static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
@@ -1548,7 +1550,9 @@ int bitmap_create(mddev_t *mddev)
mddev->thread->timeout = bitmap->daemon_sleep * HZ;
- return bitmap_update_sb(bitmap);
+ bitmap_update_sb(bitmap);
+
+ return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0;
error:
bitmap_free(bitmap);
diff .prev/drivers/md/md.c ./drivers/md/md.c
--- .prev/drivers/md/md.c 2007-05-21 11:18:22.000000000 +1000
+++ ./drivers/md/md.c 2007-05-21 11:18:23.000000000 +1000
@@ -1640,7 +1640,6 @@ static void sync_sbs(mddev_t * mddev, in
static void md_update_sb(mddev_t * mddev, int force_change)
{
- int err;
struct list_head *tmp;
mdk_rdev_t *rdev;
int sync_req;
@@ -1727,7 +1726,7 @@ repeat:
"md: updating %s RAID superblock on device (in sync %d)\n",
mdname(mddev),mddev->in_sync);
- err = bitmap_update_sb(mddev->bitmap);
+ bitmap_update_sb(mddev->bitmap);
ITERATE_RDEV(mddev,rdev,tmp) {
char b[BDEVNAME_SIZE];
dprintk(KERN_INFO "md: ");
diff .prev/drivers/md/raid10.c ./drivers/md/raid10.c
--- .prev/drivers/md/raid10.c 2007-05-21 11:17:57.000000000 +1000
+++ ./drivers/md/raid10.c 2007-05-21 11:18:23.000000000 +1000
@@ -1510,8 +1510,7 @@ static void raid10d(mddev_t *mddev)
blk_remove_plug(mddev->queue);
spin_unlock_irqrestore(&conf->device_lock, flags);
/* flush any pending bitmap writes to disk before proceeding w/ I/O */
- if (bitmap_unplug(mddev->bitmap) != 0)
- printk("%s: bitmap file write failed!\n", mdname(mddev));
+ bitmap_unplug(mddev->bitmap);
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
diff .prev/drivers/md/raid1.c ./drivers/md/raid1.c
--- .prev/drivers/md/raid1.c 2007-05-21 11:17:57.000000000 +1000
+++ ./drivers/md/raid1.c 2007-05-21 11:18:23.000000000 +1000
@@ -1519,8 +1519,7 @@ static void raid1d(mddev_t *mddev)
blk_remove_plug(mddev->queue);
spin_unlock_irqrestore(&conf->device_lock, flags);
/* flush any pending bitmap writes to disk before proceeding w/ I/O */
- if (bitmap_unplug(mddev->bitmap) != 0)
- printk("%s: bitmap file write failed!\n", mdname(mddev));
+ bitmap_unplug(mddev->bitmap);
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
diff .prev/include/linux/raid/bitmap.h ./include/linux/raid/bitmap.h
--- .prev/include/linux/raid/bitmap.h 2007-05-21 11:17:57.000000000 +1000
+++ ./include/linux/raid/bitmap.h 2007-05-21 11:18:23.000000000 +1000
@@ -262,7 +262,7 @@ int bitmap_active(struct bitmap *bitmap
char *file_path(struct file *file, char *buf, int count);
void bitmap_print_sb(struct bitmap *bitmap);
-int bitmap_update_sb(struct bitmap *bitmap);
+void bitmap_update_sb(struct bitmap *bitmap);
int bitmap_setallbits(struct bitmap *bitmap);
void bitmap_write_all(struct bitmap *bitmap);
@@ -278,8 +278,8 @@ int bitmap_start_sync(struct bitmap *bit
void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int aborted);
void bitmap_close_sync(struct bitmap *bitmap);
-int bitmap_unplug(struct bitmap *bitmap);
-int bitmap_daemon_work(struct bitmap *bitmap);
+void bitmap_unplug(struct bitmap *bitmap);
+void bitmap_daemon_work(struct bitmap *bitmap);
#endif
#endif
-
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