Commit c3a7abf0 authored by Ryusuke Konishi's avatar Ryusuke Konishi
Browse files

nilfs2: support contiguous lookup of blocks 



Although get_block() callback function can return extent of contiguous
blocks with bh->b_size, nilfs_get_block() function did not support
this feature.

This adds contiguous lookup feature to the block mapping codes of
nilfs, and allows the nilfs_get_blocks() function to return the extent
information by applying the feature.

Signed-off-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
parent fa032744

fs/nilfs2/bmap.c

+11 −1
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ 
#include "dat.h"

#include "alloc.h"



static struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)

struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)

{

	return nilfs_dat_inode(NILFS_I_NILFS(bmap->b_inode));

}
@@ -58,6 +58,16 @@ int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level, 
	return ret;

}



int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,

			     unsigned maxblocks)

{

	int ret;



	down_read(&bmap->b_sem);

	ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);

	up_read(&bmap->b_sem);

	return ret;

}



/**

 * nilfs_bmap_lookup - find a record

fs/nilfs2/bmap.h

+4 −0
Original line number Diff line number Diff line
@@ -64,6 +64,8 @@ struct nilfs_bmap_stats { 
 */

struct nilfs_bmap_operations {

	int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);

	int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,

				 unsigned);

	int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);

	int (*bop_delete)(struct nilfs_bmap *, __u64);

	void (*bop_clear)(struct nilfs_bmap *);
@@ -140,6 +142,7 @@ int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 
int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);

void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);

int nilfs_bmap_lookup(struct nilfs_bmap *, unsigned long, unsigned long *);

int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned);

int nilfs_bmap_insert(struct nilfs_bmap *, unsigned long, unsigned long);

int nilfs_bmap_delete(struct nilfs_bmap *, unsigned long);

int nilfs_bmap_last_key(struct nilfs_bmap *, unsigned long *);
@@ -160,6 +163,7 @@ void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 
/*

 * Internal use only

 */

struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);

int nilfs_bmap_prepare_alloc_v(struct nilfs_bmap *,

			       union nilfs_bmap_ptr_req *);

void nilfs_bmap_commit_alloc_v(struct nilfs_bmap *,

fs/nilfs2/btree.c

+84 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include "btnode.h"

#include "btree.h"

#include "alloc.h"

#include "dat.h"



/**

 * struct nilfs_btree_path - A path on which B-tree operations are executed
@@ -595,6 +596,87 @@ static int nilfs_btree_lookup(const struct nilfs_bmap *bmap, 
	return ret;

}



static int nilfs_btree_lookup_contig(const struct nilfs_bmap *bmap,

				     __u64 key, __u64 *ptrp, unsigned maxblocks)

{

	struct nilfs_btree *btree = (struct nilfs_btree *)bmap;

	struct nilfs_btree_path *path;

	struct nilfs_btree_node *node;

	struct inode *dat = NULL;

	__u64 ptr, ptr2;

	sector_t blocknr;

	int level = NILFS_BTREE_LEVEL_NODE_MIN;

	int ret, cnt, index, maxlevel;



	path = nilfs_btree_alloc_path(btree);

	if (path == NULL)

		return -ENOMEM;

	nilfs_btree_init_path(btree, path);

	ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level);

	if (ret < 0)

		goto out;



	if (NILFS_BMAP_USE_VBN(bmap)) {

		dat = nilfs_bmap_get_dat(bmap);

		ret = nilfs_dat_translate(dat, ptr, &blocknr);

		if (ret < 0)

			goto out;

		ptr = blocknr;

	}

	cnt = 1;

	if (cnt == maxblocks)

		goto end;



	maxlevel = nilfs_btree_height(btree) - 1;

	node = nilfs_btree_get_node(btree, path, level);

	index = path[level].bp_index + 1;

	for (;;) {

		while (index < nilfs_btree_node_get_nchildren(btree, node)) {

			if (nilfs_btree_node_get_key(btree, node, index) !=

			    key + cnt)

				goto end;

			ptr2 = nilfs_btree_node_get_ptr(btree, node, index);

			if (dat) {

				ret = nilfs_dat_translate(dat, ptr2, &blocknr);

				if (ret < 0)

					goto out;

				ptr2 = blocknr;

			}

			if (ptr2 != ptr + cnt || ++cnt == maxblocks)

				goto end;

			index++;

			continue;

		}

		if (level == maxlevel)

			break;



		/* look-up right sibling node */

		node = nilfs_btree_get_node(btree, path, level + 1);

		index = path[level + 1].bp_index + 1;

		if (index >= nilfs_btree_node_get_nchildren(btree, node) ||

		    nilfs_btree_node_get_key(btree, node, index) != key + cnt)

			break;

		ptr2 = nilfs_btree_node_get_ptr(btree, node, index);

		path[level + 1].bp_index = index;



		brelse(path[level].bp_bh);

		path[level].bp_bh = NULL;

		ret = nilfs_btree_get_block(btree, ptr2, &path[level].bp_bh);

		if (ret < 0)

			goto out;

		node = nilfs_btree_get_nonroot_node(btree, path, level);

		index = 0;

		path[level].bp_index = index;

	}

 end:

	*ptrp = ptr;

	ret = cnt;

 out:

	nilfs_btree_clear_path(btree, path);

	nilfs_btree_free_path(btree, path);

	return ret;

}



static void nilfs_btree_promote_key(struct nilfs_btree *btree,

				    struct nilfs_btree_path *path,

				    int level, __u64 key)
@@ -2187,6 +2269,7 @@ static int nilfs_btree_mark(struct nilfs_bmap *bmap, __u64 key, int level) 


static const struct nilfs_bmap_operations nilfs_btree_ops = {

	.bop_lookup		=	nilfs_btree_lookup,

	.bop_lookup_contig	=	nilfs_btree_lookup_contig,

	.bop_insert		=	nilfs_btree_insert,

	.bop_delete		=	nilfs_btree_delete,

	.bop_clear		=	NULL,
@@ -2206,6 +2289,7 @@ static const struct nilfs_bmap_operations nilfs_btree_ops = { 


static const struct nilfs_bmap_operations nilfs_btree_ops_gc = {

	.bop_lookup		=	NULL,

	.bop_lookup_contig	=	NULL,

	.bop_insert		=	NULL,

	.bop_delete		=	NULL,

	.bop_clear		=	NULL,

fs/nilfs2/direct.c

+43 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include "page.h"

#include "direct.h"

#include "alloc.h"

#include "dat.h"



static inline __le64 *nilfs_direct_dptrs(const struct nilfs_direct *direct)

{
@@ -62,6 +63,47 @@ static int nilfs_direct_lookup(const struct nilfs_bmap *bmap, 
	return 0;

}



static int nilfs_direct_lookup_contig(const struct nilfs_bmap *bmap,

				      __u64 key, __u64 *ptrp,

				      unsigned maxblocks)

{

	struct nilfs_direct *direct = (struct nilfs_direct *)bmap;

	struct inode *dat = NULL;

	__u64 ptr, ptr2;

	sector_t blocknr;

	int ret, cnt;



	if (key > NILFS_DIRECT_KEY_MAX ||

	    (ptr = nilfs_direct_get_ptr(direct, key)) ==

	    NILFS_BMAP_INVALID_PTR)

		return -ENOENT;



	if (NILFS_BMAP_USE_VBN(bmap)) {

		dat = nilfs_bmap_get_dat(bmap);

		ret = nilfs_dat_translate(dat, ptr, &blocknr);

		if (ret < 0)

			return ret;

		ptr = blocknr;

	}



	maxblocks = min_t(unsigned, maxblocks, NILFS_DIRECT_KEY_MAX - key + 1);

	for (cnt = 1; cnt < maxblocks &&

		     (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) !=

		     NILFS_BMAP_INVALID_PTR;

	     cnt++) {

		if (dat) {

			ret = nilfs_dat_translate(dat, ptr2, &blocknr);

			if (ret < 0)

				return ret;

			ptr2 = blocknr;

		}

		if (ptr2 != ptr + cnt)

			break;

	}

	*ptrp = ptr;

	return cnt;

}



static __u64

nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key)

{
@@ -367,6 +409,7 @@ static int nilfs_direct_assign(struct nilfs_bmap *bmap, 


static const struct nilfs_bmap_operations nilfs_direct_ops = {

	.bop_lookup		=	nilfs_direct_lookup,

	.bop_lookup_contig	=	nilfs_direct_lookup_contig,

	.bop_insert		=	nilfs_direct_insert,

	.bop_delete		=	nilfs_direct_delete,

	.bop_clear		=	NULL,

fs/nilfs2/inode.c

+8 −7
Original line number Diff line number Diff line
@@ -43,22 +43,23 @@ 
 *

 * This function does not issue actual read request of the specified data

 * block. It is done by VFS.

 * Bulk read for direct-io is not supported yet. (should be supported)

 */

int nilfs_get_block(struct inode *inode, sector_t blkoff,

		    struct buffer_head *bh_result, int create)

{

	struct nilfs_inode_info *ii = NILFS_I(inode);

	unsigned long blknum = 0;

	__u64 blknum = 0;

	int err = 0, ret;

	struct inode *dat = nilfs_dat_inode(NILFS_I_NILFS(inode));

	unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;



	/* This exclusion control is a workaround; should be revised */

	down_read(&NILFS_MDT(dat)->mi_sem);	/* XXX */

	ret = nilfs_bmap_lookup(ii->i_bmap, (unsigned long)blkoff, &blknum);

	up_read(&NILFS_MDT(dat)->mi_sem);	/* XXX */

	if (ret == 0) {	/* found */

	down_read(&NILFS_MDT(dat)->mi_sem);

	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);

	up_read(&NILFS_MDT(dat)->mi_sem);

	if (ret >= 0) {	/* found */

		map_bh(bh_result, inode->i_sb, blknum);

		if (ret > 0)

			bh_result->b_size = (ret << inode->i_blkbits);

		goto out;

	}

	/* data block was not found */

CRA Git | Maintained and supported by SUSTech CRA and CCSE