Commit 86479a04 authored by Chris Mason's avatar Chris Mason Committed by David Woodhouse
Browse files

Add support for defragging files via btrfsctl -d. Avoid OOM on extent tree 


defrag.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 8e21528f

fs/btrfs/ctree.c

+4 −0
Original line number Diff line number Diff line
@@ -217,6 +217,9 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans, 
		       root->fs_info->generation);

		WARN_ON(1);

	}

	if (buffer_defrag_done(parent))

		return 0;



	parent_node = btrfs_buffer_node(parent);

	parent_nritems = btrfs_header_nritems(&parent_node->header);

	parent_level = btrfs_header_level(&parent_node->header);
@@ -274,6 +277,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans, 
		*last_ret = search_start;

		if (parent_level == 1)

			clear_buffer_defrag(tmp_bh);

		set_buffer_defrag_done(tmp_bh);

		brelse(tmp_bh);

	}

	return err;

fs/btrfs/disk-io.h

+2 −0
Original line number Diff line number Diff line
@@ -26,9 +26,11 @@ 
enum btrfs_bh_state_bits {

	BH_Checked = BH_PrivateStart,

	BH_Defrag,

	BH_DefragDone,

};

BUFFER_FNS(Checked, checked);

BUFFER_FNS(Defrag, defrag);

BUFFER_FNS(DefragDone, defrag_done);



static inline struct btrfs_node *btrfs_buffer_node(struct buffer_head *bh)

{

fs/btrfs/extent_map.c

+10 −6
Original line number Diff line number Diff line
@@ -10,6 +10,12 @@ 
#include <linux/blkdev.h>

#include "extent_map.h"



/* temporary define until extent_map moves out of btrfs */

struct kmem_cache *btrfs_cache_create(const char *name, size_t size,

				       unsigned long extra_flags,

				       void (*ctor)(void *, struct kmem_cache *,

						    unsigned long));



static struct kmem_cache *extent_map_cache;

static struct kmem_cache *extent_state_cache;
@@ -32,14 +38,12 @@ struct tree_entry { 


void __init extent_map_init(void)

{

	extent_map_cache = kmem_cache_create("extent_map",

					    sizeof(struct extent_map), 0,

					    SLAB_RECLAIM_ACCOUNT |

	extent_map_cache = btrfs_cache_create("extent_map",

					    sizeof(struct extent_map),

					    SLAB_DESTROY_BY_RCU,

					    NULL);

	extent_state_cache = kmem_cache_create("extent_state",

					    sizeof(struct extent_state), 0,

					    SLAB_RECLAIM_ACCOUNT |

	extent_state_cache = btrfs_cache_create("extent_state",

					    sizeof(struct extent_state),

					    SLAB_DESTROY_BY_RCU,

					    NULL);

}

fs/btrfs/inode.c

+81 −12
Original line number Diff line number Diff line
@@ -1904,6 +1904,70 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen) 
	return ret;

}



static unsigned long force_ra(struct address_space *mapping,

			      struct file_ra_state *ra, struct file *file,

			      pgoff_t offset, pgoff_t last_index)

{

	pgoff_t req_size;



#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)

	req_size = last_index - offset + 1;

	offset = page_cache_readahead(mapping, ra, file, offset, req_size);

	return offset;

#else

	req_size = min(last_index - offset + 1, (pgoff_t)128);

	page_cache_sync_readahead(mapping, ra, file, offset, req_size);

	return offset + req_size;

#endif

}



int btrfs_defrag_file(struct file *file) {

	struct inode *inode = file->f_path.dentry->d_inode;

	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;

	struct page *page;

	unsigned long last_index;

	unsigned long ra_index = 0;

	u64 page_start;

	u64 page_end;

	unsigned long i;



	mutex_lock(&inode->i_mutex);

	last_index = inode->i_size >> PAGE_CACHE_SHIFT;

	for (i = 0; i <= last_index; i++) {

		if (i == ra_index) {

			ra_index = force_ra(inode->i_mapping, &file->f_ra,

					    file, ra_index, last_index);

		}

		page = grab_cache_page(inode->i_mapping, i);

		if (!page)

			goto out_unlock;

		if (!PageUptodate(page)) {

			btrfs_readpage(NULL, page);

			lock_page(page);

			if (!PageUptodate(page)) {

				unlock_page(page);

				page_cache_release(page);

				goto out_unlock;

			}

		}

		page_start = page->index << PAGE_CACHE_SHIFT;

		page_end = page_start + PAGE_CACHE_SIZE - 1;



		lock_extent(em_tree, page_start, page_end, GFP_NOFS);

		set_extent_delalloc(em_tree, page_start,

				    page_end, GFP_NOFS);

		unlock_extent(em_tree, page_start, page_end, GFP_NOFS);

		set_page_dirty(page);

		unlock_page(page);

		page_cache_release(page);

		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);

	}



out_unlock:

	mutex_unlock(&inode->i_mutex);

	return 0;

}



int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int

		cmd, unsigned long arg)

{
@@ -1948,10 +2012,14 @@ int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int 
		break;



	case BTRFS_IOC_DEFRAG:

		if (S_ISDIR(inode->i_mode)) {

			mutex_lock(&root->fs_info->fs_mutex);

			btrfs_defrag_root(root, 0);

			btrfs_defrag_root(root->fs_info->extent_root, 0);

			mutex_unlock(&root->fs_info->fs_mutex);

		} else if (S_ISREG(inode->i_mode)) {

			btrfs_defrag_file(filp);

		}

		ret = 0;

		break;

	default:
@@ -2018,7 +2086,7 @@ void btrfs_destroy_cachep(void) 
		kmem_cache_destroy(btrfs_path_cachep);

}



static struct kmem_cache *cache_create(const char *name, size_t size,

struct kmem_cache *btrfs_cache_create(const char *name, size_t size,

				       unsigned long extra_flags,

				       void (*ctor)(void *, struct kmem_cache *,

						    unsigned long))
@@ -2033,27 +2101,28 @@ static struct kmem_cache *cache_create(const char *name, size_t size, 


int btrfs_init_cachep(void)

{

	btrfs_inode_cachep = cache_create("btrfs_inode_cache",

	btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",

					  sizeof(struct btrfs_inode),

					  0, init_once);

	if (!btrfs_inode_cachep)

		goto fail;

	btrfs_trans_handle_cachep = cache_create("btrfs_trans_handle_cache",

	btrfs_trans_handle_cachep =

			btrfs_cache_create("btrfs_trans_handle_cache",

					   sizeof(struct btrfs_trans_handle),

					   0, NULL);

	if (!btrfs_trans_handle_cachep)

		goto fail;

	btrfs_transaction_cachep = cache_create("btrfs_transaction_cache",

	btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",

					     sizeof(struct btrfs_transaction),

					     0, NULL);

	if (!btrfs_transaction_cachep)

		goto fail;

	btrfs_path_cachep = cache_create("btrfs_path_cache",

	btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",

					 sizeof(struct btrfs_transaction),

					 0, NULL);

	if (!btrfs_path_cachep)

		goto fail;

	btrfs_bit_radix_cachep = cache_create("btrfs_radix", 256,

	btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,

					      SLAB_DESTROY_BY_RCU, NULL);

	if (!btrfs_bit_radix_cachep)

		goto fail;

fs/btrfs/tree-defrag.c

+3 −0
Original line number Diff line number Diff line
@@ -113,6 +113,8 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans, 
	}

	WARN_ON(*level < 0);

	WARN_ON(*level >= BTRFS_MAX_LEVEL);

	clear_buffer_defrag(path->nodes[*level]);

	clear_buffer_defrag_done(path->nodes[*level]);

	btrfs_block_release(root, path->nodes[*level]);

	path->nodes[*level] = NULL;

	*level += 1;
@@ -143,6 +145,7 @@ static int defrag_walk_up(struct btrfs_trans_handle *trans, 
			return 0;

		} else {

			clear_buffer_defrag(path->nodes[*level]);

			clear_buffer_defrag_done(path->nodes[*level]);

			btrfs_block_release(root, path->nodes[*level]);

			path->nodes[*level] = NULL;

			*level = i + 1;