From: NeilBrown <neilb@suse.de>
To: linux-raid@vger.kernel.org
Subject: [md PATCH 04/24] md/bitmap: centralise allocation of bitmap file pages.
Date: Tue, 17 Apr 2012 18:43:40 +1000 [thread overview]
Message-ID: <20120417084340.6433.12553.stgit@notabene.brown> (raw)
In-Reply-To: <20120417084324.6433.68345.stgit@notabene.brown>
Instead of allocating pages in read_sb_page, read_page and
bitmap_read_sb, allocate them all in bitmap_init_from disk.
Also replace the hack of calling "attach_page_buffers(page, NULL)" to
ensure that free_buffer() won't complain, by putting a test for
PagePrivate in free_buffer().
Signed-off-by: NeilBrown <neilb@suse.de>
---
drivers/md/bitmap.c | 149 +++++++++++++++++++++++----------------------------
1 file changed, 68 insertions(+), 81 deletions(-)
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 9cc42ba..5629d4a 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -130,22 +130,14 @@ static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
*/
/* IO operations when bitmap is stored near all superblocks */
-static struct page *read_sb_page(struct mddev *mddev, loff_t offset,
- struct page *page,
- unsigned long index, int size)
+static int read_sb_page(struct mddev *mddev, loff_t offset,
+ struct page *page,
+ unsigned long index, int size)
{
/* choose a good rdev and read the page from there */
struct md_rdev *rdev;
sector_t target;
- int did_alloc = 0;
-
- if (!page) {
- page = alloc_page(GFP_KERNEL);
- if (!page)
- return ERR_PTR(-ENOMEM);
- did_alloc = 1;
- }
rdev_for_each(rdev, mddev) {
if (! test_bit(In_sync, &rdev->flags)
@@ -158,15 +150,10 @@ static struct page *read_sb_page(struct mddev *mddev, loff_t offset,
roundup(size, bdev_logical_block_size(rdev->bdev)),
page, READ, true)) {
page->index = index;
- attach_page_buffers(page, NULL); /* so that free_buffer will
- * quietly no-op */
- return page;
+ return 0;
}
}
- if (did_alloc)
- put_page(page);
- return ERR_PTR(-EIO);
-
+ return -EIO;
}
static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mddev)
@@ -325,8 +312,12 @@ __clear_page_buffers(struct page *page)
}
static void free_buffers(struct page *page)
{
- struct buffer_head *bh = page_buffers(page);
+ struct buffer_head *bh;
+ if (!PagePrivate(page))
+ return;
+
+ bh = page_buffers(page);
while (bh) {
struct buffer_head *next = bh->b_this_page;
free_buffer_head(bh);
@@ -343,11 +334,12 @@ static void free_buffers(struct page *page)
* This usage is similar to how swap files are handled, and allows us
* to write to a file with no concerns of memory allocation failing.
*/
-static struct page *read_page(struct file *file, unsigned long index,
- struct bitmap *bitmap,
- unsigned long count)
+static int read_page(struct file *file, unsigned long index,
+ struct bitmap *bitmap,
+ unsigned long count,
+ struct page *page)
{
- struct page *page = NULL;
+ int ret = 0;
struct inode *inode = file->f_path.dentry->d_inode;
struct buffer_head *bh;
sector_t block;
@@ -355,16 +347,9 @@ static struct page *read_page(struct file *file, unsigned long index,
pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
(unsigned long long)index << PAGE_SHIFT);
- page = alloc_page(GFP_KERNEL);
- if (!page)
- page = ERR_PTR(-ENOMEM);
- if (IS_ERR(page))
- goto out;
-
bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0);
if (!bh) {
- put_page(page);
- page = ERR_PTR(-ENOMEM);
+ ret = -ENOMEM;
goto out;
}
attach_page_buffers(page, bh);
@@ -376,8 +361,7 @@ static struct page *read_page(struct file *file, unsigned long index,
bh->b_blocknr = bmap(inode, block);
if (bh->b_blocknr == 0) {
/* Cannot use this file! */
- free_buffers(page);
- page = ERR_PTR(-EINVAL);
+ ret = -EINVAL;
goto out;
}
bh->b_bdev = inode->i_sb->s_bdev;
@@ -400,17 +384,15 @@ static struct page *read_page(struct file *file, unsigned long index,
wait_event(bitmap->write_wait,
atomic_read(&bitmap->pending_writes)==0);
- if (bitmap->flags & BITMAP_WRITE_ERROR) {
- free_buffers(page);
- page = ERR_PTR(-EIO);
- }
+ if (bitmap->flags & BITMAP_WRITE_ERROR)
+ ret = -EIO;
out:
- if (IS_ERR(page))
- printk(KERN_ALERT "md: bitmap read error: (%dB @ %llu): %ld\n",
+ if (ret)
+ printk(KERN_ALERT "md: bitmap read error: (%dB @ %llu): %d\n",
(int)PAGE_SIZE,
(unsigned long long)index << PAGE_SHIFT,
- PTR_ERR(page));
- return page;
+ ret);
+ return ret;
}
/*
@@ -552,6 +534,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
unsigned long chunksize, daemon_sleep, write_behind;
unsigned long long events;
int err = -EINVAL;
+ struct page *sb_page;
if (!bitmap->file && !bitmap->mddev->bitmap_info.offset) {
chunksize = 128 * 1024 * 1024;
@@ -562,24 +545,27 @@ static int bitmap_read_sb(struct bitmap *bitmap)
goto out_no_sb;
}
/* page 0 is the superblock, read it... */
+ sb_page = alloc_page(GFP_KERNEL);
+ if (!sb_page)
+ return -ENOMEM;
+ bitmap->sb_page = sb_page;
+
if (bitmap->file) {
loff_t isize = i_size_read(bitmap->file->f_mapping->host);
int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
- bitmap->sb_page = read_page(bitmap->file, 0, bitmap, bytes);
+ err = read_page(bitmap->file, 0,
+ bitmap, bytes, sb_page);
} else {
- bitmap->sb_page = read_sb_page(bitmap->mddev,
- bitmap->mddev->bitmap_info.offset,
- NULL,
- 0, sizeof(bitmap_super_t));
+ err = read_sb_page(bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ sb_page,
+ 0, sizeof(bitmap_super_t));
}
- if (IS_ERR(bitmap->sb_page)) {
- err = PTR_ERR(bitmap->sb_page);
- bitmap->sb_page = NULL;
+ if (err)
return err;
- }
- sb = kmap_atomic(bitmap->sb_page);
+ sb = kmap_atomic(sb_page);
chunksize = le32_to_cpu(sb->chunksize);
daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
@@ -948,7 +934,8 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int n
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;
+ int pnum;
+ struct page *page = NULL;
unsigned long num_pages, bit_cnt = 0;
struct file *file;
unsigned long bytes, offset;
@@ -999,6 +986,22 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
if (!bitmap->filemap)
goto err;
+ pnum = 0;
+ offset = 0;
+ if (bitmap->sb_page) {
+ bitmap->filemap[0] = bitmap->sb_page;
+ pnum = 1;
+ offset = sizeof(bitmap_super_t);
+ }
+ for ( ; pnum < num_pages; pnum++) {
+ bitmap->filemap[pnum] = alloc_page(GFP_KERNEL);
+ if (!bitmap->filemap[pnum]) {
+ bitmap->file_pages = pnum;
+ goto err;
+ }
+ }
+ bitmap->file_pages = pnum;
+
/* 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)),
@@ -1019,39 +1022,22 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
count = bytes - index * PAGE_SIZE;
else
count = PAGE_SIZE;
- if (index == 0 && bitmap->sb_page) {
- /*
- * if we're here then the superblock page
- * contains some bits (PAGE_SIZE != sizeof sb)
- * we've already read it in, so just use it
- */
- page = bitmap->sb_page;
- offset = sizeof(bitmap_super_t);
- if (!file)
- page = read_sb_page(
- bitmap->mddev,
- bitmap->mddev->bitmap_info.offset,
- page,
- index, count);
- } else if (file) {
- page = read_page(file, index, bitmap, count);
- offset = 0;
- } else {
- page = read_sb_page(bitmap->mddev,
- bitmap->mddev->bitmap_info.offset,
- NULL,
- index, count);
- offset = 0;
- }
- if (IS_ERR(page)) { /* read error */
- ret = PTR_ERR(page);
+ page = bitmap->filemap[index];
+ if (file)
+ ret = read_page(file, index, bitmap,
+ count, page);
+ else
+ ret = read_sb_page(
+ bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ page,
+ index, count);
+
+ if (ret)
goto err;
- }
oldindex = index;
- oldpage = page;
- bitmap->filemap[bitmap->file_pages++] = page;
bitmap->last_page_size = count;
if (outofdate) {
@@ -1085,6 +1071,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
needed);
bit_cnt++;
}
+ offset = 0;
}
printk(KERN_INFO "%s: bitmap initialized from disk: "
next prev parent reply other threads:[~2012-04-17 8:43 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-17 8:43 [md PATCH 00/24] Allow bitmaps to be resized NeilBrown
2012-04-17 8:43 ` [md PATCH 02/24] md/bitmap: add new 'space' attribute for bitmaps NeilBrown
2012-04-17 8:43 ` [md PATCH 01/24] md/bitmap: disentangle two different 'pending' flags NeilBrown
2012-04-17 8:43 ` [md PATCH 09/24] md/bitmap: move storage allocation from bitmap_load to bitmap_create NeilBrown
2012-04-17 8:43 ` NeilBrown [this message]
2012-04-17 8:43 ` [md PATCH 03/24] md/bitmap: allow a bitmap with no backing storage NeilBrown
2012-04-17 8:43 ` [md PATCH 06/24] md/bitmap: move some fields of 'struct bitmap' into a 'storage' substruct NeilBrown
2012-04-17 8:43 ` [md PATCH 05/24] md/bitmap: change *_page_attr() to take a page number, not a page NeilBrown
2012-04-17 8:43 ` [md PATCH 07/24] md/bitmap: store bytes in file rather than just in last page NeilBrown
2012-04-17 8:43 ` [md PATCH 08/24] md/bitmap: separate bitmap file allocation to its own function NeilBrown
2012-04-17 8:43 ` [md PATCH 15/24] md/bitmap: merge bitmap_file_unmap and bitmap_file_put NeilBrown
2012-04-17 8:43 ` [md PATCH 14/24] md/bitmap: remove async freeing of bitmap file NeilBrown
2012-04-17 8:43 ` [md PATCH 12/24] md/bitmap: use set_bit, test_bit, etc for operation on bitmap->flags NeilBrown
2012-04-17 8:43 ` [md PATCH 13/24] md/bitmap: convert some spin_lock_irqsave to spin_lock_irq NeilBrown
2012-04-17 8:43 ` [md PATCH 10/24] md/bitmap: remove bitmap_mask_state NeilBrown
2012-04-17 8:43 ` [md PATCH 16/24] md/bitmap: make _page_attr bitops atomic NeilBrown
2012-04-17 8:43 ` [md PATCH 11/24] md/bitmap: remove single-bit manipulation on sb->state NeilBrown
2012-04-17 8:43 ` [md PATCH 22/24] md: allow array to be resized while bitmap is present NeilBrown
2012-04-17 8:43 ` [md PATCH 21/24] md/bitmap: make sure reshape request are reflected in superblock NeilBrown
2012-04-17 8:43 ` [md PATCH 20/24] md/bitmap: add bitmap_resize function to allow bitmap resizing NeilBrown
2012-04-17 8:43 ` [md PATCH 19/24] md/bitmap: use DIV_ROUND_UP instead of open-code NeilBrown
2012-04-17 8:43 ` [md PATCH 17/24] md/bitmap: make bitmap bitops atomic NeilBrown
2012-04-17 8:43 ` [md PATCH 18/24] md/bitmap: create a 'struct bitmap_counts' substructure of 'struct bitmap' NeilBrown
2012-04-17 8:43 ` [md PATCH 23/24] md/raid10: resize bitmap when required during reshape NeilBrown
2012-04-17 8:43 ` [md PATCH 24/24] md/raid5: Allow reshape while a bitmap is present NeilBrown
2012-04-18 2:07 ` [md PATCH 00/24] Allow bitmaps to be resized Jack Wang
2012-04-18 3:35 ` NeilBrown
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