| /* |
| * bitmap.c two-level bitmap (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003 |
| * |
| * bitmap_create - sets up the bitmap structure |
| * bitmap_destroy - destroys the bitmap structure |
| * |
| * additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.: |
| * - added disk storage for bitmap |
| * - changes to allow various bitmap chunk sizes |
| */ |
| |
| /* |
| * Still to do: |
| * |
| * flush after percent set rather than just time based. (maybe both). |
| */ |
| |
| #include <linux/blkdev.h> |
| #include <linux/module.h> |
| #include <linux/errno.h> |
| #include <linux/slab.h> |
| #include <linux/init.h> |
| #include <linux/timer.h> |
| #include <linux/sched.h> |
| #include <linux/list.h> |
| #include <linux/file.h> |
| #include <linux/mount.h> |
| #include <linux/buffer_head.h> |
| #include <linux/seq_file.h> |
| #include "md.h" |
| #include "bitmap.h" |
| |
| static inline char *bmname(struct bitmap *bitmap) |
| { |
| return bitmap->mddev ? mdname(bitmap->mddev) : "mdX"; |
| } |
| |
| /* |
| * check a page and, if necessary, allocate it (or hijack it if the alloc fails) |
| * |
| * 1) check to see if this page is allocated, if it's not then try to alloc |
| * 2) if the alloc fails, set the page's hijacked flag so we'll use the |
| * page pointer directly as a counter |
| * |
| * if we find our page, we increment the page's refcount so that it stays |
| * allocated while we're using it |
| */ |
| static int bitmap_checkpage(struct bitmap *bitmap, |
| unsigned long page, int create) |
| __releases(bitmap->lock) |
| __acquires(bitmap->lock) |
| { |
| unsigned char *mappage; |
| |
| if (page >= bitmap->pages) { |
| /* This can happen if bitmap_start_sync goes beyond |
| * End-of-device while looking for a whole page. |
| * It is harmless. |
| */ |
| return -EINVAL; |
| } |
| |
| if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */ |
| return 0; |
| |
| if (bitmap->bp[page].map) /* page is already allocated, just return */ |
| return 0; |
| |
| if (!create) |
| return -ENOENT; |
| |
| /* this page has not been allocated yet */ |
| |
| spin_unlock_irq(&bitmap->lock); |
| mappage = kzalloc(PAGE_SIZE, GFP_NOIO); |
| spin_lock_irq(&bitmap->lock); |
| |
| if (mappage == NULL) { |
| pr_debug("%s: bitmap map page allocation failed, hijacking\n", |
| bmname(bitmap)); |
| /* failed - set the hijacked flag so that we can use the |
| * pointer as a counter */ |
| if (!bitmap->bp[page].map) |
| bitmap->bp[page].hijacked = 1; |
| } else if (bitmap->bp[page].map || |
| bitmap->bp[page].hijacked) { |
| /* somebody beat us to getting the page */ |
| kfree(mappage); |
| return 0; |
| } else { |
| |
| /* no page was in place and we have one, so install it */ |
| |
| bitmap->bp[page].map = mappage; |
| bitmap->missing_pages--; |
| } |
| return 0; |
| } |
| |
| /* if page is completely empty, put it back on the free list, or dealloc it */ |
| /* if page was hijacked, unmark the flag so it might get alloced next time */ |
| /* Note: lock should be held when calling this */ |
| static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page) |
| { |
| char *ptr; |
| |
| if (bitmap->bp[page].count) /* page is still busy */ |
| return; |
| |
| /* page is no longer in use, it can be released */ |
| |
| if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */ |
| bitmap->bp[page].hijacked = 0; |
| bitmap->bp[page].map = NULL; |
| } else { |
| /* normal case, free the page */ |
| ptr = bitmap->bp[page].map; |
| bitmap->bp[page].map = NULL; |
| bitmap->missing_pages++; |
| kfree(ptr); |
| } |
| } |
| |
| /* |
| * bitmap file handling - read and write the bitmap file and its superblock |
| */ |
| |
| /* |
| * basic page I/O operations |
| */ |
| |
| /* IO operations when bitmap is stored near all superblocks */ |
| 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; |
| |
| rdev_for_each(rdev, mddev) { |
| if (! test_bit(In_sync, &rdev->flags) |
| || test_bit(Faulty, &rdev->flags)) |
| continue; |
| |
| target = offset + index * (PAGE_SIZE/512); |
| |
| if (sync_page_io(rdev, target, |
| roundup(size, bdev_logical_block_size(rdev->bdev)), |
| page, READ, true)) { |
| page->index = index; |
| return 0; |
| } |
| } |
| return -EIO; |
| } |
| |
| static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mddev) |
| { |
| /* Iterate the disks of an mddev, using rcu to protect access to the |
| * linked list, and raising the refcount of devices we return to ensure |
| * they don't disappear while in use. |
| * As devices are only added or removed when raid_disk is < 0 and |
| * nr_pending is 0 and In_sync is clear, the entries we return will |
| * still be in the same position on the list when we re-enter |
| * list_for_each_continue_rcu. |
| */ |
| struct list_head *pos; |
| rcu_read_lock(); |
| if (rdev == NULL) |
| /* start at the beginning */ |
| pos = &mddev->disks; |
| else { |
| /* release the previous rdev and start from there. */ |
| rdev_dec_pending(rdev, mddev); |
| pos = &rdev->same_set; |
| } |
| list_for_each_continue_rcu(pos, &mddev->disks) { |
| rdev = list_entry(pos, struct md_rdev, same_set); |
| if (rdev->raid_disk >= 0 && |
| !test_bit(Faulty, &rdev->flags)) { |
| /* this is a usable devices */ |
| atomic_inc(&rdev->nr_pending); |
| rcu_read_unlock(); |
| return rdev; |
| } |
| } |
| rcu_read_unlock(); |
| return NULL; |
| } |
| |
| static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait) |
| { |
| struct md_rdev *rdev = NULL; |
| struct block_device *bdev; |
| struct mddev *mddev = bitmap->mddev; |
| struct bitmap_storage *store = &bitmap->storage; |
| |
| while ((rdev = next_active_rdev(rdev, mddev)) != NULL) { |
| int size = PAGE_SIZE; |
| loff_t offset = mddev->bitmap_info.offset; |
| |
| bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev; |
| |
| if (page->index == store->file_pages-1) { |
| int last_page_size = store->bytes & (PAGE_SIZE-1); |
| if (last_page_size == 0) |
| last_page_size = PAGE_SIZE; |
| size = roundup(last_page_size, |
| bdev_logical_block_size(bdev)); |
| } |
| /* Just make sure we aren't corrupting data or |
| * metadata |
| */ |
| if (mddev->external) { |
| /* Bitmap could be anywhere. */ |
| if (rdev->sb_start + offset + (page->index |
| * (PAGE_SIZE/512)) |
| > rdev->data_offset |
| && |
| rdev->sb_start + offset |
| < (rdev->data_offset + mddev->dev_sectors |
| + (PAGE_SIZE/512))) |
| goto bad_alignment; |
| } else if (offset < 0) { |
| /* DATA BITMAP METADATA */ |
| if (offset |
| + (long)(page->index * (PAGE_SIZE/512)) |
| + size/512 > 0) |
| /* bitmap runs in to metadata */ |
| goto bad_alignment; |
| if (rdev->data_offset + mddev->dev_sectors |
| > rdev->sb_start + offset) |
| /* data runs in to bitmap */ |
| goto bad_alignment; |
| } else if (rdev->sb_start < rdev->data_offset) { |
| /* METADATA BITMAP DATA */ |
| if (rdev->sb_start |
| + offset |
| + page->index*(PAGE_SIZE/512) + size/512 |
| > rdev->data_offset) |
| /* bitmap runs in to data */ |
| goto bad_alignment; |
| } else { |
| /* DATA METADATA BITMAP - no problems */ |
| } |
| md_super_write(mddev, rdev, |
| rdev->sb_start + offset |
| + page->index * (PAGE_SIZE/512), |
| size, |
| page); |
| } |
| |
| if (wait) |
| md_super_wait(mddev); |
| return 0; |
| |
| bad_alignment: |
| return -EINVAL; |
| } |
| |
| static void bitmap_file_kick(struct bitmap *bitmap); |
| /* |
| * write out a page to a file |
| */ |
| static void write_page(struct bitmap *bitmap, struct page *page, int wait) |
| { |
| struct buffer_head *bh; |
| |
| if (bitmap->storage.file == NULL) { |
| switch (write_sb_page(bitmap, page, wait)) { |
| case -EINVAL: |
| bitmap->flags |= BITMAP_WRITE_ERROR; |
| } |
| } else { |
| |
| 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 | REQ_SYNC, bh); |
| bh = bh->b_this_page; |
| } |
| |
| if (wait) |
| wait_event(bitmap->write_wait, |
| atomic_read(&bitmap->pending_writes)==0); |
| } |
| if (bitmap->flags & BITMAP_WRITE_ERROR) |
| bitmap_file_kick(bitmap); |
| } |
| |
| static void end_bitmap_write(struct buffer_head *bh, int uptodate) |
| { |
| struct bitmap *bitmap = bh->b_private; |
| unsigned long flags; |
| |
| if (!uptodate) { |
| spin_lock_irqsave(&bitmap->lock, flags); |
| bitmap->flags |= BITMAP_WRITE_ERROR; |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| } |
| if (atomic_dec_and_test(&bitmap->pending_writes)) |
| wake_up(&bitmap->write_wait); |
| } |
| |
| /* copied from buffer.c */ |
| static void |
| __clear_page_buffers(struct page *page) |
| { |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| page_cache_release(page); |
| } |
| static void free_buffers(struct page *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); |
| bh = next; |
| } |
| __clear_page_buffers(page); |
| put_page(page); |
| } |
| |
| /* read a page from a file. |
| * We both read the page, and attach buffers to the page to record the |
| * address of each block (using bmap). These addresses will be used |
| * to write the block later, completely bypassing the filesystem. |
| * 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 int read_page(struct file *file, unsigned long index, |
| struct bitmap *bitmap, |
| unsigned long count, |
| struct page *page) |
| { |
| int ret = 0; |
| struct inode *inode = file->f_path.dentry->d_inode; |
| struct buffer_head *bh; |
| sector_t block; |
| |
| pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE, |
| (unsigned long long)index << PAGE_SHIFT); |
| |
| bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0); |
| if (!bh) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| attach_page_buffers(page, bh); |
| block = index << (PAGE_SHIFT - inode->i_blkbits); |
| while (bh) { |
| if (count == 0) |
| bh->b_blocknr = 0; |
| else { |
| bh->b_blocknr = bmap(inode, block); |
| if (bh->b_blocknr == 0) { |
| /* Cannot use this file! */ |
| ret = -EINVAL; |
| goto out; |
| } |
| bh->b_bdev = inode->i_sb->s_bdev; |
| if (count < (1<<inode->i_blkbits)) |
| count = 0; |
| else |
| count -= (1<<inode->i_blkbits); |
| |
| 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) |
| ret = -EIO; |
| out: |
| if (ret) |
| printk(KERN_ALERT "md: bitmap read error: (%dB @ %llu): %d\n", |
| (int)PAGE_SIZE, |
| (unsigned long long)index << PAGE_SHIFT, |
| ret); |
| return ret; |
| } |
| |
| /* |
| * bitmap file superblock operations |
| */ |
| |
| /* update the event counter and sync the superblock to disk */ |
| void bitmap_update_sb(struct bitmap *bitmap) |
| { |
| bitmap_super_t *sb; |
| |
| if (!bitmap || !bitmap->mddev) /* no bitmap for this array */ |
| return; |
| if (bitmap->mddev->bitmap_info.external) |
| return; |
| if (!bitmap->storage.sb_page) /* no superblock */ |
| return; |
| sb = kmap_atomic(bitmap->storage.sb_page); |
| sb->events = cpu_to_le64(bitmap->mddev->events); |
| if (bitmap->mddev->events < bitmap->events_cleared) |
| /* rocking back to read-only */ |
| bitmap->events_cleared = bitmap->mddev->events; |
| sb->events_cleared = cpu_to_le64(bitmap->events_cleared); |
| sb->state = cpu_to_le32(bitmap->flags); |
| /* Just in case these have been changed via sysfs: */ |
| sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ); |
| sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind); |
| kunmap_atomic(sb); |
| write_page(bitmap, bitmap->storage.sb_page, 1); |
| } |
| |
| /* print out the bitmap file superblock */ |
| void bitmap_print_sb(struct bitmap *bitmap) |
| { |
| bitmap_super_t *sb; |
| |
| if (!bitmap || !bitmap->storage.sb_page) |
| return; |
| sb = kmap_atomic(bitmap->storage.sb_page); |
| printk(KERN_DEBUG "%s: bitmap file superblock:\n", bmname(bitmap)); |
| printk(KERN_DEBUG " magic: %08x\n", le32_to_cpu(sb->magic)); |
| printk(KERN_DEBUG " version: %d\n", le32_to_cpu(sb->version)); |
| printk(KERN_DEBUG " uuid: %08x.%08x.%08x.%08x\n", |
| *(__u32 *)(sb->uuid+0), |
| *(__u32 *)(sb->uuid+4), |
| *(__u32 *)(sb->uuid+8), |
| *(__u32 *)(sb->uuid+12)); |
| printk(KERN_DEBUG " events: %llu\n", |
| (unsigned long long) le64_to_cpu(sb->events)); |
| printk(KERN_DEBUG "events cleared: %llu\n", |
| (unsigned long long) le64_to_cpu(sb->events_cleared)); |
| printk(KERN_DEBUG " state: %08x\n", le32_to_cpu(sb->state)); |
| printk(KERN_DEBUG " chunksize: %d B\n", le32_to_cpu(sb->chunksize)); |
| 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_atomic(sb); |
| } |
| |
| /* |
| * bitmap_new_disk_sb |
| * @bitmap |
| * |
| * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb |
| * reads and verifies the on-disk bitmap superblock and populates bitmap_info. |
| * This function verifies 'bitmap_info' and populates the on-disk bitmap |
| * structure, which is to be written to disk. |
| * |
| * Returns: 0 on success, -Exxx on error |
| */ |
| static int bitmap_new_disk_sb(struct bitmap *bitmap) |
| { |
| bitmap_super_t *sb; |
| unsigned long chunksize, daemon_sleep, write_behind; |
| int err = -EINVAL; |
| |
| bitmap->storage.sb_page = alloc_page(GFP_KERNEL); |
| if (IS_ERR(bitmap->storage.sb_page)) { |
| err = PTR_ERR(bitmap->storage.sb_page); |
| bitmap->storage.sb_page = NULL; |
| return err; |
| } |
| bitmap->storage.sb_page->index = 0; |
| |
| sb = kmap_atomic(bitmap->storage.sb_page); |
| |
| sb->magic = cpu_to_le32(BITMAP_MAGIC); |
| sb->version = cpu_to_le32(BITMAP_MAJOR_HI); |
| |
| chunksize = bitmap->mddev->bitmap_info.chunksize; |
| BUG_ON(!chunksize); |
| if (!is_power_of_2(chunksize)) { |
| kunmap_atomic(sb); |
| printk(KERN_ERR "bitmap chunksize not a power of 2\n"); |
| return -EINVAL; |
| } |
| sb->chunksize = cpu_to_le32(chunksize); |
| |
| daemon_sleep = bitmap->mddev->bitmap_info.daemon_sleep; |
| if (!daemon_sleep || |
| (daemon_sleep < 1) || (daemon_sleep > MAX_SCHEDULE_TIMEOUT)) { |
| printk(KERN_INFO "Choosing daemon_sleep default (5 sec)\n"); |
| daemon_sleep = 5 * HZ; |
| } |
| sb->daemon_sleep = cpu_to_le32(daemon_sleep); |
| bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep; |
| |
| /* |
| * FIXME: write_behind for RAID1. If not specified, what |
| * is a good choice? We choose COUNTER_MAX / 2 arbitrarily. |
| */ |
| write_behind = bitmap->mddev->bitmap_info.max_write_behind; |
| if (write_behind > COUNTER_MAX) |
| write_behind = COUNTER_MAX / 2; |
| sb->write_behind = cpu_to_le32(write_behind); |
| bitmap->mddev->bitmap_info.max_write_behind = write_behind; |
| |
| /* keep the array size field of the bitmap superblock up to date */ |
| sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors); |
| |
| memcpy(sb->uuid, bitmap->mddev->uuid, 16); |
| |
| bitmap->flags |= BITMAP_STALE; |
| sb->state = cpu_to_le32(bitmap->flags); |
| bitmap->events_cleared = bitmap->mddev->events; |
| sb->events_cleared = cpu_to_le64(bitmap->mddev->events); |
| |
| kunmap_atomic(sb); |
| |
| return 0; |
| } |
| |
| /* read the superblock from the bitmap file and initialize some bitmap fields */ |
| static int bitmap_read_sb(struct bitmap *bitmap) |
| { |
| char *reason = NULL; |
| bitmap_super_t *sb; |
| unsigned long chunksize, daemon_sleep, write_behind; |
| unsigned long long events; |
| int err = -EINVAL; |
| struct page *sb_page; |
| |
| if (!bitmap->storage.file && !bitmap->mddev->bitmap_info.offset) { |
| chunksize = 128 * 1024 * 1024; |
| daemon_sleep = 5 * HZ; |
| write_behind = 0; |
| bitmap->flags = BITMAP_STALE; |
| err = 0; |
| goto out_no_sb; |
| } |
| /* page 0 is the superblock, read it... */ |
| sb_page = alloc_page(GFP_KERNEL); |
| if (!sb_page) |
| return -ENOMEM; |
| bitmap->storage.sb_page = sb_page; |
| |
| if (bitmap->storage.file) { |
| loff_t isize = i_size_read(bitmap->storage.file->f_mapping->host); |
| int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize; |
| |
| err = read_page(bitmap->storage.file, 0, |
| bitmap, bytes, sb_page); |
| } else { |
| err = read_sb_page(bitmap->mddev, |
| bitmap->mddev->bitmap_info.offset, |
| sb_page, |
| 0, sizeof(bitmap_super_t)); |
| } |
| if (err) |
| return err; |
| |
| sb = kmap_atomic(sb_page); |
| |
| chunksize = le32_to_cpu(sb->chunksize); |
| daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ; |
| write_behind = le32_to_cpu(sb->write_behind); |
| |
| /* verify that the bitmap-specific fields are valid */ |
| if (sb->magic != cpu_to_le32(BITMAP_MAGIC)) |
| reason = "bad magic"; |
| else if (le32_to_cpu(sb->version) < BITMAP_MAJOR_LO || |
| le32_to_cpu(sb->version) > BITMAP_MAJOR_HI) |
| reason = "unrecognized superblock version"; |
| else if (chunksize < 512) |
| reason = "bitmap chunksize too small"; |
| else if (!is_power_of_2(chunksize)) |
| reason = "bitmap chunksize not a power of 2"; |
| else if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT) |
| reason = "daemon sleep period out of range"; |
| 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); |
| goto out; |
| } |
| |
| /* keep the array size field of the bitmap superblock up to date */ |
| sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors); |
| |
| if (bitmap->mddev->persistent) { |
| /* |
| * We have a persistent array superblock, so compare the |
| * bitmap's UUID and event counter to the mddev's |
| */ |
| if (memcmp(sb->uuid, bitmap->mddev->uuid, 16)) { |
| printk(KERN_INFO |
| "%s: bitmap superblock UUID mismatch\n", |
| bmname(bitmap)); |
| goto out; |
| } |
| events = le64_to_cpu(sb->events); |
| if (events < bitmap->mddev->events) { |
| printk(KERN_INFO |
| "%s: bitmap file is out of date (%llu < %llu) " |
| "-- forcing full recovery\n", |
| bmname(bitmap), events, |
| (unsigned long long) bitmap->mddev->events); |
| bitmap->flags |= BITMAP_STALE; |
| } |
| } |
| |
| /* assign fields using values from superblock */ |
| bitmap->flags |= le32_to_cpu(sb->state); |
| if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN) |
| bitmap->flags |= BITMAP_HOSTENDIAN; |
| bitmap->events_cleared = le64_to_cpu(sb->events_cleared); |
| err = 0; |
| out: |
| kunmap_atomic(sb); |
| out_no_sb: |
| if (bitmap->flags & BITMAP_STALE) |
| bitmap->events_cleared = bitmap->mddev->events; |
| bitmap->mddev->bitmap_info.chunksize = chunksize; |
| bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep; |
| bitmap->mddev->bitmap_info.max_write_behind = write_behind; |
| if (err) |
| bitmap_print_sb(bitmap); |
| return err; |
| } |
| |
| /* |
| * general bitmap file operations |
| */ |
| |
| /* |
| * on-disk bitmap: |
| * |
| * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap |
| * file a page at a time. There's a superblock at the start of the file. |
| */ |
| /* calculate the index of the page that contains this bit */ |
| static inline unsigned long file_page_index(struct bitmap_storage *store, |
| unsigned long chunk) |
| { |
| if (store->sb_page) |
| chunk += sizeof(bitmap_super_t) << 3; |
| return chunk >> PAGE_BIT_SHIFT; |
| } |
| |
| /* calculate the (bit) offset of this bit within a page */ |
| static inline unsigned long file_page_offset(struct bitmap_storage *store, |
| unsigned long chunk) |
| { |
| if (store->sb_page) |
| chunk += sizeof(bitmap_super_t) << 3; |
| return chunk & (PAGE_BITS - 1); |
| } |
| |
| /* |
| * return a pointer to the page in the filemap that contains the given bit |
| * |
| * this lookup is complicated by the fact that the bitmap sb might be exactly |
| * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page |
| * 0 or page 1 |
| */ |
| static inline struct page *filemap_get_page(struct bitmap_storage *store, |
| unsigned long chunk) |
| { |
| if (file_page_index(store, chunk) >= store->file_pages) |
| return NULL; |
| return store->filemap[file_page_index(store, chunk) |
| - file_page_index(store, 0)]; |
| } |
| |
| static int bitmap_storage_alloc(struct bitmap_storage *store, |
| unsigned long chunks, int with_super) |
| { |
| int pnum; |
| unsigned long num_pages; |
| unsigned long bytes; |
| |
| bytes = DIV_ROUND_UP(chunks, 8); |
| if (with_super) |
| bytes += sizeof(bitmap_super_t); |
| |
| num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE); |
| |
| store->filemap = kmalloc(sizeof(struct page *) |
| * num_pages, GFP_KERNEL); |
| if (!store->filemap) |
| return -ENOMEM; |
| |
| if (with_super && !store->sb_page) { |
| store->sb_page = alloc_page(GFP_KERNEL); |
| if (store->sb_page == NULL) |
| return -ENOMEM; |
| store->sb_page->index = 0; |
| } |
| pnum = 0; |
| if (store->sb_page) { |
| store->filemap[0] = store->sb_page; |
| pnum = 1; |
| } |
| for ( ; pnum < num_pages; pnum++) { |
| store->filemap[pnum] = alloc_page(GFP_KERNEL); |
| if (!store->filemap[pnum]) { |
| store->file_pages = pnum; |
| return -ENOMEM; |
| } |
| store->filemap[pnum]->index = pnum; |
| } |
| store->file_pages = pnum; |
| |
| /* We need 4 bits per page, rounded up to a multiple |
| * of sizeof(unsigned long) */ |
| store->filemap_attr = kzalloc( |
| roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)), |
| GFP_KERNEL); |
| if (!store->filemap_attr) |
| return -ENOMEM; |
| |
| store->bytes = bytes; |
| |
| return 0; |
| } |
| |
| static void bitmap_file_unmap(struct bitmap *bitmap) |
| { |
| struct page **map, *sb_page; |
| unsigned long *attr; |
| int pages; |
| unsigned long flags; |
| struct bitmap_storage *store = &bitmap->storage; |
| |
| spin_lock_irqsave(&bitmap->lock, flags); |
| map = store->filemap; |
| store->filemap = NULL; |
| attr = store->filemap_attr; |
| store->filemap_attr = NULL; |
| pages = store->file_pages; |
| store->file_pages = 0; |
| sb_page = store->sb_page; |
| store->sb_page = NULL; |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| |
| while (pages--) |
| if (map[pages] != sb_page) /* 0 is sb_page, release it below */ |
| free_buffers(map[pages]); |
| kfree(map); |
| kfree(attr); |
| |
| if (sb_page) |
| free_buffers(sb_page); |
| } |
| |
| static void bitmap_file_put(struct bitmap *bitmap) |
| { |
| struct file *file; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&bitmap->lock, flags); |
| file = bitmap->storage.file; |
| bitmap->storage.file = NULL; |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| |
| if (file) |
| wait_event(bitmap->write_wait, |
| atomic_read(&bitmap->pending_writes)==0); |
| bitmap_file_unmap(bitmap); |
| |
| if (file) { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| invalidate_mapping_pages(inode->i_mapping, 0, -1); |
| fput(file); |
| } |
| } |
| |
| /* |
| * bitmap_file_kick - if an error occurs while manipulating the bitmap file |
| * then it is no longer reliable, so we stop using it and we mark the file |
| * as failed in the superblock |
| */ |
| static void bitmap_file_kick(struct bitmap *bitmap) |
| { |
| char *path, *ptr = NULL; |
| |
| if (!(bitmap->flags & BITMAP_STALE)) { |
| bitmap->flags |= BITMAP_STALE; |
| bitmap_update_sb(bitmap); |
| |
| if (bitmap->storage.file) { |
| path = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| if (path) |
| ptr = d_path(&bitmap->storage.file->f_path, |
| path, PAGE_SIZE); |
| |
| printk(KERN_ALERT |
| "%s: kicking failed bitmap file %s from array!\n", |
| bmname(bitmap), IS_ERR(ptr) ? "" : ptr); |
| |
| kfree(path); |
| } else |
| printk(KERN_ALERT |
| "%s: disabling internal bitmap due to errors\n", |
| bmname(bitmap)); |
| } |
| |
| bitmap_file_put(bitmap); |
| |
| return; |
| } |
| |
| enum bitmap_page_attr { |
| BITMAP_PAGE_DIRTY = 0, /* there are set bits that need to be synced */ |
| BITMAP_PAGE_PENDING = 1, /* there are bits that are being cleaned. |
| * i.e. counter is 1 or 2. */ |
| BITMAP_PAGE_NEEDWRITE = 2, /* there are cleared bits that need to be synced */ |
| }; |
| |
| static inline void set_page_attr(struct bitmap *bitmap, int pnum, |
| enum bitmap_page_attr attr) |
| { |
| __set_bit((pnum<<2) + attr, bitmap->storage.filemap_attr); |
| } |
| |
| static inline void clear_page_attr(struct bitmap *bitmap, int pnum, |
| enum bitmap_page_attr attr) |
| { |
| __clear_bit((pnum<<2) + attr, bitmap->storage.filemap_attr); |
| } |
| |
| static inline unsigned long test_page_attr(struct bitmap *bitmap, int pnum, |
| enum bitmap_page_attr attr) |
| { |
| return test_bit((pnum<<2) + attr, bitmap->storage.filemap_attr); |
| } |
| |
| /* |
| * bitmap_file_set_bit -- called before performing a write to the md device |
| * to set (and eventually sync) a particular bit in the bitmap file |
| * |
| * we set the bit immediately, then we record the page number so that |
| * when an unplug occurs, we can flush the dirty pages out to disk |
| */ |
| static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block) |
| { |
| unsigned long bit; |
| struct page *page; |
| void *kaddr; |
| unsigned long chunk = block >> bitmap->chunkshift; |
| |
| page = filemap_get_page(&bitmap->storage, chunk); |
| if (!page) |
| return; |
| bit = file_page_offset(&bitmap->storage, chunk); |
| |
| /* set the bit */ |
| kaddr = kmap_atomic(page); |
| if (bitmap->flags & BITMAP_HOSTENDIAN) |
| set_bit(bit, kaddr); |
| else |
| __set_bit_le(bit, kaddr); |
| kunmap_atomic(kaddr); |
| pr_debug("set file bit %lu page %lu\n", bit, page->index); |
| /* record page number so it gets flushed to disk when unplug occurs */ |
| set_page_attr(bitmap, page->index, BITMAP_PAGE_DIRTY); |
| } |
| |
| static void bitmap_file_clear_bit(struct bitmap *bitmap, sector_t block) |
| { |
| unsigned long bit; |
| struct page *page; |
| void *paddr; |
| unsigned long chunk = block >> bitmap->chunkshift; |
| |
| page = filemap_get_page(&bitmap->storage, chunk); |
| if (!page) |
| return; |
| bit = file_page_offset(&bitmap->storage, chunk); |
| paddr = kmap_atomic(page); |
| if (bitmap->flags & BITMAP_HOSTENDIAN) |
| clear_bit(bit, paddr); |
| else |
| __clear_bit_le(bit, paddr); |
| kunmap_atomic(paddr); |
| if (!test_page_attr(bitmap, page->index, BITMAP_PAGE_NEEDWRITE)) { |
| set_page_attr(bitmap, page->index, BITMAP_PAGE_PENDING); |
| bitmap->allclean = 0; |
| } |
| } |
| |
| /* 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 */ |
| void bitmap_unplug(struct bitmap *bitmap) |
| { |
| unsigned long i, flags; |
| int dirty, need_write; |
| int wait = 0; |
| |
| if (!bitmap || !bitmap->storage.filemap) |
| return; |
| |
| /* look at each page to see if there are any set bits that need to be |
| * flushed out to disk */ |
| for (i = 0; i < bitmap->storage.file_pages; i++) { |
| spin_lock_irqsave(&bitmap->lock, flags); |
| if (!bitmap->storage.filemap) { |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| return; |
| } |
| dirty = test_page_attr(bitmap, i, BITMAP_PAGE_DIRTY); |
| need_write = test_page_attr(bitmap, i, BITMAP_PAGE_NEEDWRITE); |
| clear_page_attr(bitmap, i, BITMAP_PAGE_DIRTY); |
| clear_page_attr(bitmap, i, BITMAP_PAGE_NEEDWRITE); |
| if (dirty || need_write) |
| clear_page_attr(bitmap, i, BITMAP_PAGE_PENDING); |
| if (dirty) |
| wait = 1; |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| |
| if (dirty || need_write) |
| write_page(bitmap, bitmap->storage.filemap[i], 0); |
| } |
| if (wait) { /* if any writes were performed, we need to wait on them */ |
| if (bitmap->storage.file) |
| wait_event(bitmap->write_wait, |
| atomic_read(&bitmap->pending_writes)==0); |
| else |
| md_super_wait(bitmap->mddev); |
| } |
| if (bitmap->flags & BITMAP_WRITE_ERROR) |
| bitmap_file_kick(bitmap); |
| } |
| EXPORT_SYMBOL(bitmap_unplug); |
| |
| 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 |
| * Special cases: |
| * 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, sector_t start) |
| { |
| unsigned long i, chunks, index, oldindex, bit; |
| struct page *page = NULL; |
| unsigned long bit_cnt = 0; |
| struct file *file; |
| unsigned long offset; |
| int outofdate; |
| int ret = -ENOSPC; |
| void *paddr; |
| struct bitmap_storage *store = &bitmap->storage; |
| |
| chunks = bitmap->chunks; |
| file = store->file; |
| |
| if (!file && !bitmap->mddev->bitmap_info.offset) { |
| /* No permanent bitmap - fill with '1s'. */ |
| store->filemap = NULL; |
| store->file_pages = 0; |
| for (i = 0; i < chunks ; i++) { |
| /* if the disk bit is set, set the memory bit */ |
| int needed = ((sector_t)(i+1) << (bitmap->chunkshift) |
| >= start); |
| bitmap_set_memory_bits(bitmap, |
| (sector_t)i << bitmap->chunkshift, |
| needed); |
| } |
| return 0; |
| } |
| |
| outofdate = bitmap->flags & BITMAP_STALE; |
| if (outofdate) |
| printk(KERN_INFO "%s: bitmap file is out of date, doing full " |
| "recovery\n", bmname(bitmap)); |
| |
| if (file && i_size_read(file->f_mapping->host) < store->bytes) { |
| printk(KERN_INFO "%s: bitmap file too short %lu < %lu\n", |
| bmname(bitmap), |
| (unsigned long) i_size_read(file->f_mapping->host), |
| store->bytes); |
| goto err; |
| } |
| |
| oldindex = ~0L; |
| offset = 0; |
| if (!bitmap->mddev->bitmap_info.external) |
| offset = sizeof(bitmap_super_t); |
| |
| for (i = 0; i < chunks; i++) { |
| int b; |
| index = file_page_index(&bitmap->storage, i); |
| bit = file_page_offset(&bitmap->storage, i); |
| if (index != oldindex) { /* this is a new page, read it in */ |
| int count; |
| /* unmap the old page, we're done with it */ |
| if (index == store->file_pages-1) |
| count = store->bytes - index * PAGE_SIZE; |
| else |
| count = PAGE_SIZE; |
| page = store->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; |
| |
| if (outofdate) { |
| /* |
| * if bitmap is out of date, dirty the |
| * whole page and write it out |
| */ |
| paddr = kmap_atomic(page); |
| memset(paddr + offset, 0xff, |
| PAGE_SIZE - offset); |
| kunmap_atomic(paddr); |
| write_page(bitmap, page, 1); |
| |
| ret = -EIO; |
| if (bitmap->flags & BITMAP_WRITE_ERROR) |
| goto err; |
| } |
| } |
| paddr = kmap_atomic(page); |
| if (bitmap->flags & BITMAP_HOSTENDIAN) |
| b = test_bit(bit, paddr); |
| else |
| b = test_bit_le(bit, paddr); |
| kunmap_atomic(paddr); |
| if (b) { |
| /* if the disk bit is set, set the memory bit */ |
| int needed = ((sector_t)(i+1) << bitmap->chunkshift |
| >= start); |
| bitmap_set_memory_bits(bitmap, |
| (sector_t)i << bitmap->chunkshift, |
| needed); |
| bit_cnt++; |
| } |
| offset = 0; |
| } |
| |
| printk(KERN_INFO "%s: bitmap initialized from disk: " |
| "read %lu pages, set %lu of %lu bits\n", |
| bmname(bitmap), store->file_pages, |
| bit_cnt, chunks); |
| |
| return 0; |
| |
| err: |
| printk(KERN_INFO "%s: bitmap initialisation failed: %d\n", |
| bmname(bitmap), ret); |
| return ret; |
| } |
| |
| void bitmap_write_all(struct bitmap *bitmap) |
| { |
| /* We don't actually write all bitmap blocks here, |
| * just flag them as needing to be written |
| */ |
| int i; |
| |
| if (!bitmap || !bitmap->storage.filemap) |
| return; |
| if (bitmap->storage.file) |
| /* Only one copy, so nothing needed */ |
| return; |
| |
| spin_lock_irq(&bitmap->lock); |
| for (i = 0; i < bitmap->storage.file_pages; i++) |
| set_page_attr(bitmap, i, |
| BITMAP_PAGE_NEEDWRITE); |
| bitmap->allclean = 0; |
| spin_unlock_irq(&bitmap->lock); |
| } |
| |
| static void bitmap_count_page(struct bitmap *bitmap, sector_t offset, int inc) |
| { |
| sector_t chunk = offset >> bitmap->chunkshift; |
| unsigned long page = chunk >> PAGE_COUNTER_SHIFT; |
| bitmap->bp[page].count += inc; |
| bitmap_checkfree(bitmap, page); |
| } |
| |
| static void bitmap_set_pending(struct bitmap *bitmap, sector_t offset) |
| { |
| sector_t chunk = offset >> bitmap->chunkshift; |
| unsigned long page = chunk >> PAGE_COUNTER_SHIFT; |
| struct bitmap_page *bp = &bitmap->bp[page]; |
| |
| if (!bp->pending) |
| bp->pending = 1; |
| } |
| |
| static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap, |
| sector_t offset, sector_t *blocks, |
| int create); |
| |
| /* |
| * bitmap daemon -- periodically wakes up to clean bits and flush pages |
| * out to disk |
| */ |
| |
| void bitmap_daemon_work(struct mddev *mddev) |
| { |
| struct bitmap *bitmap; |
| unsigned long j; |
| unsigned long nextpage; |
| unsigned long flags; |
| sector_t blocks; |
| |
| /* Use a mutex to guard daemon_work against |
| * bitmap_destroy. |
| */ |
| mutex_lock(&mddev->bitmap_info.mutex); |
| bitmap = mddev->bitmap; |
| if (bitmap == NULL) { |
| mutex_unlock(&mddev->bitmap_info.mutex); |
| return; |
| } |
| if (time_before(jiffies, bitmap->daemon_lastrun |
| + mddev->bitmap_info.daemon_sleep)) |
| goto done; |
| |
| bitmap->daemon_lastrun = jiffies; |
| if (bitmap->allclean) { |
| mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT; |
| goto done; |
| } |
| bitmap->allclean = 1; |
| |
| /* Any file-page which is PENDING now needs to be written. |
| * So set NEEDWRITE now, then after we make any last-minute changes |
| * we will write it. |
| */ |
| spin_lock_irqsave(&bitmap->lock, flags); |
| for (j = 0; j < bitmap->storage.file_pages; j++) |
| if (test_page_attr(bitmap, j, |
| BITMAP_PAGE_PENDING)) { |
| set_page_attr(bitmap, j, |
| BITMAP_PAGE_NEEDWRITE); |
| clear_page_attr(bitmap, j, |
| BITMAP_PAGE_PENDING); |
| } |
| |
| if (bitmap->need_sync && |
| mddev->bitmap_info.external == 0) { |
| /* Arrange for superblock update as well as |
| * other changes */ |
| bitmap_super_t *sb; |
| bitmap->need_sync = 0; |
| if (bitmap->storage.filemap) { |
| sb = kmap_atomic(bitmap->storage.sb_page); |
| sb->events_cleared = |
| cpu_to_le64(bitmap->events_cleared); |
| kunmap_atomic(sb); |
| set_page_attr(bitmap, 0, |
| BITMAP_PAGE_NEEDWRITE); |
| } |
| } |
| /* Now look at the bitmap counters and if any are '2' or '1', |
| * decrement and handle accordingly. |
| */ |
| nextpage = 0; |
| for (j = 0; j < bitmap->chunks; j++) { |
| bitmap_counter_t *bmc; |
| sector_t block = (sector_t)j << bitmap->chunkshift; |
| |
| if (j == nextpage) { |
| nextpage += PAGE_COUNTER_RATIO; |
| if (!bitmap->bp[j >> PAGE_COUNTER_SHIFT].pending) { |
| j |= PAGE_COUNTER_MASK; |
| continue; |
| } |
| bitmap->bp[j >> PAGE_COUNTER_SHIFT].pending = 0; |
| } |
| bmc = bitmap_get_counter(bitmap, |
| block, |
| &blocks, 0); |
| |
| if (!bmc) { |
| j |= PAGE_COUNTER_MASK; |
| continue; |
| } |
| if (*bmc == 1 && !bitmap->need_sync) { |
| /* We can clear the bit */ |
| *bmc = 0; |
| bitmap_count_page(bitmap, block, -1); |
| bitmap_file_clear_bit(bitmap, block); |
| } else if (*bmc && *bmc <= 2) { |
| *bmc = 1; |
| bitmap_set_pending(bitmap, block); |
| bitmap->allclean = 0; |
| } |
| } |
| |
| /* Now start writeout on any page in NEEDWRITE that isn't DIRTY. |
| * DIRTY pages need to be written by bitmap_unplug so it can wait |
| * for them. |
| * If we find any DIRTY page we stop there and let bitmap_unplug |
| * handle all the rest. This is important in the case where |
| * the first blocking holds the superblock and it has been updated. |
| * We mustn't write any other blocks before the superblock. |
| */ |
| for (j = 0; j < bitmap->storage.file_pages; j++) { |
| |
| if (test_page_attr(bitmap, j, |
| BITMAP_PAGE_DIRTY)) |
| /* bitmap_unplug will handle the rest */ |
| break; |
| if (test_page_attr(bitmap, j, |
| BITMAP_PAGE_NEEDWRITE)) { |
| clear_page_attr(bitmap, j, |
| BITMAP_PAGE_NEEDWRITE); |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| write_page(bitmap, bitmap->storage.filemap[j], 0); |
| spin_lock_irqsave(&bitmap->lock, flags); |
| if (!bitmap->storage.filemap) |
| break; |
| } |
| } |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| |
| done: |
| if (bitmap->allclean == 0) |
| mddev->thread->timeout = |
| mddev->bitmap_info.daemon_sleep; |
| mutex_unlock(&mddev->bitmap_info.mutex); |
| } |
| |
| static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap, |
| sector_t offset, sector_t *blocks, |
| int create) |
| __releases(bitmap->lock) |
| __acquires(bitmap->lock) |
| { |
| /* If 'create', we might release the lock and reclaim it. |
| * The lock must have been taken with interrupts enabled. |
| * If !create, we don't release the lock. |
| */ |
| sector_t chunk = offset >> bitmap->chunkshift; |
| unsigned long page = chunk >> PAGE_COUNTER_SHIFT; |
| unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT; |
| sector_t csize; |
| int err; |
| |
| err = bitmap_checkpage(bitmap, page, create); |
| |
| if (bitmap->bp[page].hijacked || |
| bitmap->bp[page].map == NULL) |
| csize = ((sector_t)1) << (bitmap->chunkshift + |
| PAGE_COUNTER_SHIFT - 1); |
| else |
| csize = ((sector_t)1) << bitmap->chunkshift; |
| *blocks = csize - (offset & (csize - 1)); |
| |
| if (err < 0) |
| return NULL; |
| |
| /* now locked ... */ |
| |
| if (bitmap->bp[page].hijacked) { /* hijacked pointer */ |
| /* should we use the first or second counter field |
| * of the hijacked pointer? */ |
| int hi = (pageoff > PAGE_COUNTER_MASK); |
| return &((bitmap_counter_t *) |
| &bitmap->bp[page].map)[hi]; |
| } else /* page is allocated */ |
| return (bitmap_counter_t *) |
| &(bitmap->bp[page].map[pageoff]); |
| } |
| |
| int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind) |
| { |
| if (!bitmap) |
| return 0; |
| |
| if (behind) { |
| int bw; |
| atomic_inc(&bitmap->behind_writes); |
| bw = atomic_read(&bitmap->behind_writes); |
| if (bw > bitmap->behind_writes_used) |
| bitmap->behind_writes_used = bw; |
| |
| pr_debug("inc write-behind count %d/%lu\n", |
| bw, bitmap->mddev->bitmap_info.max_write_behind); |
| } |
| |
| while (sectors) { |
| sector_t blocks; |
| bitmap_counter_t *bmc; |
| |
| spin_lock_irq(&bitmap->lock); |
| bmc = bitmap_get_counter(bitmap, offset, &blocks, 1); |
| if (!bmc) { |
| spin_unlock_irq(&bitmap->lock); |
| return 0; |
| } |
| |
| if (unlikely(COUNTER(*bmc) == COUNTER_MAX)) { |
| DEFINE_WAIT(__wait); |
| /* note that it is safe to do the prepare_to_wait |
| * after the test as long as we do it before dropping |
| * the spinlock. |
| */ |
| prepare_to_wait(&bitmap->overflow_wait, &__wait, |
| TASK_UNINTERRUPTIBLE); |
| spin_unlock_irq(&bitmap->lock); |
| io_schedule(); |
| finish_wait(&bitmap->overflow_wait, &__wait); |
| continue; |
| } |
| |
| switch (*bmc) { |
| case 0: |
| bitmap_file_set_bit(bitmap, offset); |
| bitmap_count_page(bitmap, offset, 1); |
| /* fall through */ |
| case 1: |
| *bmc = 2; |
| } |
| |
| (*bmc)++; |
| |
| spin_unlock_irq(&bitmap->lock); |
| |
| offset += blocks; |
| if (sectors > blocks) |
| sectors -= blocks; |
| else |
| sectors = 0; |
| } |
| return 0; |
| } |
| EXPORT_SYMBOL(bitmap_startwrite); |
| |
| void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, |
| int success, int behind) |
| { |
| if (!bitmap) |
| return; |
| if (behind) { |
| if (atomic_dec_and_test(&bitmap->behind_writes)) |
| wake_up(&bitmap->behind_wait); |
| pr_debug("dec write-behind count %d/%lu\n", |
| atomic_read(&bitmap->behind_writes), |
| bitmap->mddev->bitmap_info.max_write_behind); |
| } |
| |
| while (sectors) { |
| sector_t blocks; |
| unsigned long flags; |
| bitmap_counter_t *bmc; |
| |
| spin_lock_irqsave(&bitmap->lock, flags); |
| bmc = bitmap_get_counter(bitmap, offset, &blocks, 0); |
| if (!bmc) { |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| return; |
| } |
| |
| if (success && !bitmap->mddev->degraded && |
| bitmap->events_cleared < bitmap->mddev->events) { |
| bitmap->events_cleared = bitmap->mddev->events; |
| bitmap->need_sync = 1; |
| sysfs_notify_dirent_safe(bitmap->sysfs_can_clear); |
| } |
| |
| if (!success && !NEEDED(*bmc)) |
| *bmc |= NEEDED_MASK; |
| |
| if (COUNTER(*bmc) == COUNTER_MAX) |
| wake_up(&bitmap->overflow_wait); |
| |
| (*bmc)--; |
| if (*bmc <= 2) { |
| bitmap_set_pending(bitmap, offset); |
| bitmap->allclean = 0; |
| } |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| offset += blocks; |
| if (sectors > blocks) |
| sectors -= blocks; |
| else |
| sectors = 0; |
| } |
| } |
| EXPORT_SYMBOL(bitmap_endwrite); |
| |
| static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, |
| int degraded) |
| { |
| bitmap_counter_t *bmc; |
| int rv; |
| if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */ |
| *blocks = 1024; |
| return 1; /* always resync if no bitmap */ |
| } |
| spin_lock_irq(&bitmap->lock); |
| bmc = bitmap_get_counter(bitmap, offset, blocks, 0); |
| rv = 0; |
| if (bmc) { |
| /* locked */ |
| if (RESYNC(*bmc)) |
| rv = 1; |
| else if (NEEDED(*bmc)) { |
| rv = 1; |
| if (!degraded) { /* don't set/clear bits if degraded */ |
| *bmc |= RESYNC_MASK; |
| *bmc &= ~NEEDED_MASK; |
| } |
| } |
| } |
| spin_unlock_irq(&bitmap->lock); |
| return rv; |
| } |
| |
| int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, |
| int degraded) |
| { |
| /* bitmap_start_sync must always report on multiples of whole |
| * pages, otherwise resync (which is very PAGE_SIZE based) will |
| * get confused. |
| * So call __bitmap_start_sync repeatedly (if needed) until |
| * At least PAGE_SIZE>>9 blocks are covered. |
| * Return the 'or' of the result. |
| */ |
| int rv = 0; |
| sector_t blocks1; |
| |
| *blocks = 0; |
| while (*blocks < (PAGE_SIZE>>9)) { |
| rv |= __bitmap_start_sync(bitmap, offset, |
| &blocks1, degraded); |
| offset += blocks1; |
| *blocks += blocks1; |
| } |
| return rv; |
| } |
| EXPORT_SYMBOL(bitmap_start_sync); |
| |
| void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted) |
| { |
| bitmap_counter_t *bmc; |
| unsigned long flags; |
| |
| if (bitmap == NULL) { |
| *blocks = 1024; |
| return; |
| } |
| spin_lock_irqsave(&bitmap->lock, flags); |
| bmc = bitmap_get_counter(bitmap, offset, blocks, 0); |
| if (bmc == NULL) |
| goto unlock; |
| /* locked */ |
| if (RESYNC(*bmc)) { |
| *bmc &= ~RESYNC_MASK; |
| |
| if (!NEEDED(*bmc) && aborted) |
| *bmc |= NEEDED_MASK; |
| else { |
| if (*bmc <= 2) { |
| bitmap_set_pending(bitmap, offset); |
| bitmap->allclean = 0; |
| } |
| } |
| } |
| unlock: |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| } |
| EXPORT_SYMBOL(bitmap_end_sync); |
| |
| void bitmap_close_sync(struct bitmap *bitmap) |
| { |
| /* Sync has finished, and any bitmap chunks that weren't synced |
| * properly have been aborted. It remains to us to clear the |
| * RESYNC bit wherever it is still on |
| */ |
| sector_t sector = 0; |
| sector_t blocks; |
| if (!bitmap) |
| return; |
| while (sector < bitmap->mddev->resync_max_sectors) { |
| bitmap_end_sync(bitmap, sector, &blocks, 0); |
| sector += blocks; |
| } |
| } |
| EXPORT_SYMBOL(bitmap_close_sync); |
| |
| void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector) |
| { |
| sector_t s = 0; |
| sector_t blocks; |
| |
| if (!bitmap) |
| return; |
| if (sector == 0) { |
| bitmap->last_end_sync = jiffies; |
| return; |
| } |
| if (time_before(jiffies, (bitmap->last_end_sync |
| + bitmap->mddev->bitmap_info.daemon_sleep))) |
| return; |
| wait_event(bitmap->mddev->recovery_wait, |
| atomic_read(&bitmap->mddev->recovery_active) == 0); |
| |
| bitmap->mddev->curr_resync_completed = sector; |
| set_bit(MD_CHANGE_CLEAN, &bitmap->mddev->flags); |
| sector &= ~((1ULL << bitmap->chunkshift) - 1); |
| s = 0; |
| while (s < sector && s < bitmap->mddev->resync_max_sectors) { |
| bitmap_end_sync(bitmap, s, &blocks, 0); |
| s += blocks; |
| } |
| bitmap->last_end_sync = jiffies; |
| sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed"); |
| } |
| EXPORT_SYMBOL(bitmap_cond_end_sync); |
| |
| 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 2 and possibly set resync_needed. They should all |
| * be 0 at this point |
| */ |
| |
| sector_t secs; |
| bitmap_counter_t *bmc; |
| spin_lock_irq(&bitmap->lock); |
| bmc = bitmap_get_counter(bitmap, offset, &secs, 1); |
| if (!bmc) { |
| spin_unlock_irq(&bitmap->lock); |
| return; |
| } |
| if (!*bmc) { |
| *bmc = 2 | (needed ? NEEDED_MASK : 0); |
| bitmap_count_page(bitmap, offset, 1); |
| bitmap_set_pending(bitmap, offset); |
| bitmap->allclean = 0; |
| } |
| spin_unlock_irq(&bitmap->lock); |
| } |
| |
| /* dirty the memory and file bits for bitmap chunks "s" to "e" */ |
| void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e) |
| { |
| unsigned long chunk; |
| |
| for (chunk = s; chunk <= e; chunk++) { |
| sector_t sec = (sector_t)chunk << bitmap->chunkshift; |
| bitmap_set_memory_bits(bitmap, sec, 1); |
| spin_lock_irq(&bitmap->lock); |
| bitmap_file_set_bit(bitmap, sec); |
| spin_unlock_irq(&bitmap->lock); |
| if (sec < bitmap->mddev->recovery_cp) |
| /* We are asserting that the array is dirty, |
| * so move the recovery_cp address back so |
| * that it is obvious that it is dirty |
| */ |
| bitmap->mddev->recovery_cp = sec; |
| } |
| } |
| |
| /* |
| * flush out any pending updates |
| */ |
| void bitmap_flush(struct mddev *mddev) |
| { |
| struct bitmap *bitmap = mddev->bitmap; |
| long sleep; |
| |
| if (!bitmap) /* there was no bitmap */ |
| return; |
| |
| /* run the daemon_work three time to ensure everything is flushed |
| * that can be |
| */ |
| sleep = mddev->bitmap_info.daemon_sleep * 2; |
| bitmap->daemon_lastrun -= sleep; |
| bitmap_daemon_work(mddev); |
| bitmap->daemon_lastrun -= sleep; |
| bitmap_daemon_work(mddev); |
| bitmap->daemon_lastrun -= sleep; |
| bitmap_daemon_work(mddev); |
| bitmap_update_sb(bitmap); |
| } |
| |
| /* |
| * free memory that was allocated |
| */ |
| static void bitmap_free(struct bitmap *bitmap) |
| { |
| unsigned long k, pages; |
| struct bitmap_page *bp; |
| |
| if (!bitmap) /* there was no bitmap */ |
| return; |
| |
| /* release the bitmap file and kill the daemon */ |
| bitmap_file_put(bitmap); |
| |
| bp = bitmap->bp; |
| pages = bitmap->pages; |
| |
| /* free all allocated memory */ |
| |
| if (bp) /* deallocate the page memory */ |
| for (k = 0; k < pages; k++) |
| if (bp[k].map && !bp[k].hijacked) |
| kfree(bp[k].map); |
| kfree(bp); |
| kfree(bitmap); |
| } |
| |
| void bitmap_destroy(struct mddev *mddev) |
| { |
| struct bitmap *bitmap = mddev->bitmap; |
| |
| if (!bitmap) /* there was no bitmap */ |
| return; |
| |
| mutex_lock(&mddev->bitmap_info.mutex); |
| mddev->bitmap = NULL; /* disconnect from the md device */ |
| mutex_unlock(&mddev->bitmap_info.mutex); |
| if (mddev->thread) |
| mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT; |
| |
| if (bitmap->sysfs_can_clear) |
| sysfs_put(bitmap->sysfs_can_clear); |
| |
| bitmap_free(bitmap); |
| } |
| |
| /* |
| * initialize the bitmap structure |
| * if this returns an error, bitmap_destroy must be called to do clean up |
| */ |
| int bitmap_create(struct mddev *mddev) |
| { |
| struct bitmap *bitmap; |
| sector_t blocks = mddev->resync_max_sectors; |
| unsigned long chunks; |
| unsigned long pages; |
| struct file *file = mddev->bitmap_info.file; |
| int err; |
| struct sysfs_dirent *bm = NULL; |
| |
| BUILD_BUG_ON(sizeof(bitmap_super_t) != 256); |
| |
| BUG_ON(file && mddev->bitmap_info.offset); |
| |
| bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL); |
| if (!bitmap) |
| return -ENOMEM; |
| |
| spin_lock_init(&bitmap->lock); |
| atomic_set(&bitmap->pending_writes, 0); |
| init_waitqueue_head(&bitmap->write_wait); |
| init_waitqueue_head(&bitmap->overflow_wait); |
| init_waitqueue_head(&bitmap->behind_wait); |
| |
| bitmap->mddev = mddev; |
| |
| if (mddev->kobj.sd) |
| bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap"); |
| if (bm) { |
| bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear"); |
| sysfs_put(bm); |
| } else |
| bitmap->sysfs_can_clear = NULL; |
| |
| bitmap->storage.file = file; |
| if (file) { |
| get_file(file); |
| /* As future accesses to this file will use bmap, |
| * and bypass the page cache, we must sync the file |
| * first. |
| */ |
| vfs_fsync(file, 1); |
| } |
| /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */ |
| if (!mddev->bitmap_info.external) { |
| /* |
| * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is |
| * instructing us to create a new on-disk bitmap instance. |
| */ |
| if (test_and_clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags)) |
| err = bitmap_new_disk_sb(bitmap); |
| else |
| err = bitmap_read_sb(bitmap); |
| } else { |
| err = 0; |
| if (mddev->bitmap_info.chunksize == 0 || |
| mddev->bitmap_info.daemon_sleep == 0) |
| /* chunksize and time_base need to be |
| * set first. */ |
| err = -EINVAL; |
| } |
| if (err) |
| goto error; |
| |
| bitmap->daemon_lastrun = jiffies; |
| bitmap->chunkshift = (ffz(~mddev->bitmap_info.chunksize) |
| - BITMAP_BLOCK_SHIFT); |
| |
| chunks = (blocks + (1 << bitmap->chunkshift) - 1) >> |
| bitmap->chunkshift; |
| pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO; |
| |
| BUG_ON(!pages); |
| |
| bitmap->chunks = chunks; |
| bitmap->pages = pages; |
| bitmap->missing_pages = pages; |
| |
| bitmap->bp = kzalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL); |
| |
| err = -ENOMEM; |
| if (!bitmap->bp) |
| goto error; |
| |
| if (file || mddev->bitmap_info.offset) { |
| err = bitmap_storage_alloc(&bitmap->storage, bitmap->chunks, |
| !mddev->bitmap_info.external); |
| if (err) |
| goto error; |
| } |
| printk(KERN_INFO "created bitmap (%lu pages) for device %s\n", |
| pages, bmname(bitmap)); |
| |
| mddev->bitmap = bitmap; |
| |
| |
| return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0; |
| |
| error: |
| bitmap_free(bitmap); |
| return err; |
| } |
| |
| int bitmap_load(struct mddev *mddev) |
| { |
| int err = 0; |
| sector_t start = 0; |
| sector_t sector = 0; |
| struct bitmap *bitmap = mddev->bitmap; |
| |
| if (!bitmap) |
| goto out; |
| |
| /* Clear out old bitmap info first: Either there is none, or we |
| * are resuming after someone else has possibly changed things, |
| * so we should forget old cached info. |
| * All chunks should be clean, but some might need_sync. |
| */ |
| while (sector < mddev->resync_max_sectors) { |
| sector_t blocks; |
| bitmap_start_sync(bitmap, sector, &blocks, 0); |
| sector += blocks; |
| } |
| bitmap_close_sync(bitmap); |
| |
| 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; |
| |
| mutex_lock(&mddev->bitmap_info.mutex); |
| err = bitmap_init_from_disk(bitmap, start); |
| mutex_unlock(&mddev->bitmap_info.mutex); |
| |
| if (err) |
| goto out; |
| bitmap->flags &= ~BITMAP_STALE; |
| |
| /* Kick recovery in case any bits were set */ |
| set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery); |
| |
| mddev->thread->timeout = mddev->bitmap_info.daemon_sleep; |
| md_wakeup_thread(mddev->thread); |
| |
| bitmap_update_sb(bitmap); |
| |
| if (bitmap->flags & BITMAP_WRITE_ERROR) |
| err = -EIO; |
| out: |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(bitmap_load); |
| |
| void bitmap_status(struct seq_file *seq, struct bitmap *bitmap) |
| { |
| unsigned long chunk_kb; |
| unsigned long flags; |
| |
| if (!bitmap) |
| return; |
| |
| spin_lock_irqsave(&bitmap->lock, flags); |
| chunk_kb = bitmap->mddev->bitmap_info.chunksize >> 10; |
| seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], " |
| "%lu%s chunk", |
| bitmap->pages - bitmap->missing_pages, |
| bitmap->pages, |
| (bitmap->pages - bitmap->missing_pages) |
| << (PAGE_SHIFT - 10), |
| chunk_kb ? chunk_kb : bitmap->mddev->bitmap_info.chunksize, |
| chunk_kb ? "KB" : "B"); |
| if (bitmap->storage.file) { |
| seq_printf(seq, ", file: "); |
| seq_path(seq, &bitmap->storage.file->f_path, " \t\n"); |
| } |
| |
| seq_printf(seq, "\n"); |
| spin_unlock_irqrestore(&bitmap->lock, flags); |
| } |
| |
| static ssize_t |
| location_show(struct mddev *mddev, char *page) |
| { |
| ssize_t len; |
| if (mddev->bitmap_info.file) |
| len = sprintf(page, "file"); |
| else if (mddev->bitmap_info.offset) |
| len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset); |
| else |
| len = sprintf(page, "none"); |
| len += sprintf(page+len, "\n"); |
| return len; |
| } |
| |
| static ssize_t |
| location_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| |
| if (mddev->pers) { |
| if (!mddev->pers->quiesce) |
| return -EBUSY; |
| if (mddev->recovery || mddev->sync_thread) |
| return -EBUSY; |
| } |
| |
| if (mddev->bitmap || mddev->bitmap_info.file || |
| mddev->bitmap_info.offset) { |
| /* bitmap already configured. Only option is to clear it */ |
| if (strncmp(buf, "none", 4) != 0) |
| return -EBUSY; |
| if (mddev->pers) { |
| mddev->pers->quiesce(mddev, 1); |
| bitmap_destroy(mddev); |
| mddev->pers->quiesce(mddev, 0); |
| } |
| mddev->bitmap_info.offset = 0; |
| if (mddev->bitmap_info.file) { |
| struct file *f = mddev->bitmap_info.file; |
| mddev->bitmap_info.file = NULL; |
| restore_bitmap_write_access(f); |
| fput(f); |
| } |
| } else { |
| /* No bitmap, OK to set a location */ |
| long long offset; |
| if (strncmp(buf, "none", 4) == 0) |
| /* nothing to be done */; |
| else if (strncmp(buf, "file:", 5) == 0) { |
| /* Not supported yet */ |
| return -EINVAL; |
| } else { |
| int rv; |
| if (buf[0] == '+') |
| rv = strict_strtoll(buf+1, 10, &offset); |
| else |
| rv = strict_strtoll(buf, 10, &offset); |
| if (rv) |
| return rv; |
| if (offset == 0) |
| return -EINVAL; |
| if (mddev->bitmap_info.external == 0 && |
| mddev->major_version == 0 && |
| offset != mddev->bitmap_info.default_offset) |
| return -EINVAL; |
| mddev->bitmap_info.offset = offset; |
| if (mddev->pers) { |
| mddev->pers->quiesce(mddev, 1); |
| rv = bitmap_create(mddev); |
| if (!rv) |
| rv = bitmap_load(mddev); |
| if (rv) { |
| bitmap_destroy(mddev); |
| mddev->bitmap_info.offset = 0; |
| } |
| mddev->pers->quiesce(mddev, 0); |
| if (rv) |
| return rv; |
| } |
| } |
| } |
| if (!mddev->external) { |
| /* Ensure new bitmap info is stored in |
| * metadata promptly. |
| */ |
| set_bit(MD_CHANGE_DEVS, &mddev->flags); |
| md_wakeup_thread(mddev->thread); |
| } |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_location = |
| __ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store); |
| |
| /* 'bitmap/space' is the space available at 'location' for the |
| * bitmap. This allows the kernel to know when it is safe to |
| * resize the bitmap to match a resized array. |
| */ |
| static ssize_t |
| space_show(struct mddev *mddev, char *page) |
| { |
| return sprintf(page, "%lu\n", mddev->bitmap_info.space); |
| } |
| |
| static ssize_t |
| space_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| unsigned long sectors; |
| int rv; |
| |
| rv = kstrtoul(buf, 10, §ors); |
| if (rv) |
| return rv; |
| |
| if (sectors == 0) |
| return -EINVAL; |
| |
| if (mddev->bitmap && |
| sectors < (mddev->bitmap->storage.bytes + 511) >> 9) |
| return -EFBIG; /* Bitmap is too big for this small space */ |
| |
| /* could make sure it isn't too big, but that isn't really |
| * needed - user-space should be careful. |
| */ |
| mddev->bitmap_info.space = sectors; |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_space = |
| __ATTR(space, S_IRUGO|S_IWUSR, space_show, space_store); |
| |
| static ssize_t |
| timeout_show(struct mddev *mddev, char *page) |
| { |
| ssize_t len; |
| unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ; |
| unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ; |
| |
| len = sprintf(page, "%lu", secs); |
| if (jifs) |
| len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs)); |
| len += sprintf(page+len, "\n"); |
| return len; |
| } |
| |
| static ssize_t |
| timeout_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| /* timeout can be set at any time */ |
| unsigned long timeout; |
| int rv = strict_strtoul_scaled(buf, &timeout, 4); |
| if (rv) |
| return rv; |
| |
| /* just to make sure we don't overflow... */ |
| if (timeout >= LONG_MAX / HZ) |
| return -EINVAL; |
| |
| timeout = timeout * HZ / 10000; |
| |
| if (timeout >= MAX_SCHEDULE_TIMEOUT) |
| timeout = MAX_SCHEDULE_TIMEOUT-1; |
| if (timeout < 1) |
| timeout = 1; |
| mddev->bitmap_info.daemon_sleep = timeout; |
| if (mddev->thread) { |
| /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then |
| * the bitmap is all clean and we don't need to |
| * adjust the timeout right now |
| */ |
| if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) { |
| mddev->thread->timeout = timeout; |
| md_wakeup_thread(mddev->thread); |
| } |
| } |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_timeout = |
| __ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store); |
| |
| static ssize_t |
| backlog_show(struct mddev *mddev, char *page) |
| { |
| return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind); |
| } |
| |
| static ssize_t |
| backlog_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| unsigned long backlog; |
| int rv = strict_strtoul(buf, 10, &backlog); |
| if (rv) |
| return rv; |
| if (backlog > COUNTER_MAX) |
| return -EINVAL; |
| mddev->bitmap_info.max_write_behind = backlog; |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_backlog = |
| __ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store); |
| |
| static ssize_t |
| chunksize_show(struct mddev *mddev, char *page) |
| { |
| return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize); |
| } |
| |
| static ssize_t |
| chunksize_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| /* Can only be changed when no bitmap is active */ |
| int rv; |
| unsigned long csize; |
| if (mddev->bitmap) |
| return -EBUSY; |
| rv = strict_strtoul(buf, 10, &csize); |
| if (rv) |
| return rv; |
| if (csize < 512 || |
| !is_power_of_2(csize)) |
| return -EINVAL; |
| mddev->bitmap_info.chunksize = csize; |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_chunksize = |
| __ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store); |
| |
| static ssize_t metadata_show(struct mddev *mddev, char *page) |
| { |
| return sprintf(page, "%s\n", (mddev->bitmap_info.external |
| ? "external" : "internal")); |
| } |
| |
| static ssize_t metadata_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| if (mddev->bitmap || |
| mddev->bitmap_info.file || |
| mddev->bitmap_info.offset) |
| return -EBUSY; |
| if (strncmp(buf, "external", 8) == 0) |
| mddev->bitmap_info.external = 1; |
| else if (strncmp(buf, "internal", 8) == 0) |
| mddev->bitmap_info.external = 0; |
| else |
| return -EINVAL; |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_metadata = |
| __ATTR(metadata, S_IRUGO|S_IWUSR, metadata_show, metadata_store); |
| |
| static ssize_t can_clear_show(struct mddev *mddev, char *page) |
| { |
| int len; |
| if (mddev->bitmap) |
| len = sprintf(page, "%s\n", (mddev->bitmap->need_sync ? |
| "false" : "true")); |
| else |
| len = sprintf(page, "\n"); |
| return len; |
| } |
| |
| static ssize_t can_clear_store(struct mddev *mddev, const char *buf, size_t len) |
| { |
| if (mddev->bitmap == NULL) |
| return -ENOENT; |
| if (strncmp(buf, "false", 5) == 0) |
| mddev->bitmap->need_sync = 1; |
| else if (strncmp(buf, "true", 4) == 0) { |
| if (mddev->degraded) |
| return -EBUSY; |
| mddev->bitmap->need_sync = 0; |
| } else |
| return -EINVAL; |
| return len; |
| } |
| |
| static struct md_sysfs_entry bitmap_can_clear = |
| __ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store); |
| |
| static ssize_t |
| behind_writes_used_show(struct mddev *mddev, char *page) |
| { |
| if (mddev->bitmap == NULL) |
| return sprintf(page, "0\n"); |
| return sprintf(page, "%lu\n", |
| mddev->bitmap->behind_writes_used); |
| } |
| |
| static ssize_t |
| behind_writes_used_reset(struct mddev *mddev, const char *buf, size_t len) |
| { |
| if (mddev->bitmap) |
| mddev->bitmap->behind_writes_used = 0; |
| return len; |
| } |
| |
| static struct md_sysfs_entry max_backlog_used = |
| __ATTR(max_backlog_used, S_IRUGO | S_IWUSR, |
| behind_writes_used_show, behind_writes_used_reset); |
| |
| static struct attribute *md_bitmap_attrs[] = { |
| &bitmap_location.attr, |
| &bitmap_space.attr, |
| &bitmap_timeout.attr, |
| &bitmap_backlog.attr, |
| &bitmap_chunksize.attr, |
| &bitmap_metadata.attr, |
| &bitmap_can_clear.attr, |
| &max_backlog_used.attr, |
| NULL |
| }; |
| struct attribute_group md_bitmap_group = { |
| .name = "bitmap", |
| .attrs = md_bitmap_attrs, |
| }; |
| |