From ce25c31bdd3b39266debd86a7732007e05983a67 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 26 Jun 2006 00:27:49 -0700 Subject: [PATCH] [PATCH] md: Change md/bitmap file handling to use bmap to file blocks-fix Fix problems with new bmap based access to bitmap files. 1/ When not using a file based bitmap, attach a NULL list of buffers to each page so the common free_buffer routine can cope. 2/ Use submit_bh to read as well as write, rather than vfs_read. This makes read and write more symetric. 3/ sync the file before reading, to ensure that the page cache has no dirty pages that might get written out later. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/bitmap.c | 47 ++++++++++++++++++++++----------------------- 1 file changed, 23 insertions(+), 24 deletions(-) diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index bedd66e9e8..ebbd2d8562 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -247,6 +247,8 @@ static struct page *read_sb_page(mddev_t *mddev, long offset, unsigned long inde if (sync_page_io(rdev->bdev, target, PAGE_SIZE, page, READ)) { page->index = index; + attach_page_buffers(page, NULL); /* so that free_buffer will + * quietly no-op */ return page; } } @@ -349,11 +351,8 @@ static struct page *read_page(struct file *file, unsigned long index, { struct page *page = NULL; struct inode *inode = file->f_dentry->d_inode; - loff_t pos = index << PAGE_SHIFT; - int ret; struct buffer_head *bh; sector_t block; - mm_segment_t oldfs; PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_SIZE, (unsigned long long)index << PAGE_SHIFT); @@ -364,18 +363,6 @@ static struct page *read_page(struct file *file, unsigned long index, if (IS_ERR(page)) goto out; - oldfs = get_fs(); - set_fs(KERNEL_DS); - ret = vfs_read(file, (char __user*) page_address(page), count, &pos); - set_fs(oldfs); - - if (ret >= 0 && ret != count) - ret = -EIO; - if (ret < 0) { - put_page(page); - page = ERR_PTR(ret); - goto out; - } bh = alloc_page_buffers(page, 1<i_blkbits, 0); if (!bh) { put_page(page); @@ -403,12 +390,22 @@ static struct page *read_page(struct file *file, unsigned long index, bh->b_end_io = end_bitmap_write; bh->b_private = bitmap; + atomic_inc(&bitmap->pending_writes); + set_buffer_locked(bh); + set_buffer_mapped(bh); + submit_bh(READ, bh); } block++; bh = bh->b_this_page; } - page->index = 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); + } out: if (IS_ERR(page)) printk(KERN_ALERT "md: bitmap read error: (%dB @ %Lu): %ld\n", @@ -1415,15 +1412,20 @@ int bitmap_create(mddev_t *mddev) return -ENOMEM; spin_lock_init(&bitmap->lock); + atomic_set(&bitmap->pending_writes, 0); + init_waitqueue_head(&bitmap->write_wait); + bitmap->mddev = mddev; bitmap->file = file; bitmap->offset = mddev->bitmap_offset; - if (file) get_file(file); - - /* Ensure we read fresh data */ - invalidate_inode_pages(file->f_dentry->d_inode->i_mapping); - + if (file) { + get_file(file); + do_sync_file_range(file, 0, LLONG_MAX, + SYNC_FILE_RANGE_WAIT_BEFORE | + SYNC_FILE_RANGE_WRITE | + SYNC_FILE_RANGE_WAIT_AFTER); + } /* read superblock from bitmap file (this sets bitmap->chunksize) */ err = bitmap_read_sb(bitmap); if (err) @@ -1446,9 +1448,6 @@ int bitmap_create(mddev_t *mddev) bitmap->syncchunk = ~0UL; - atomic_set(&bitmap->pending_writes, 0); - init_waitqueue_head(&bitmap->write_wait); - #ifdef INJECT_FATAL_FAULT_1 bitmap->bp = NULL; #else -- 2.39.5