Commit ff8f33c8 authored by Steven Whitehouse's avatar Steven Whitehouse
Browse files

GFS2: New truncate sequence 



This updates GFS2's truncate code to use the new truncate
sequence correctly. This is a stepping stone to being
able to remove ip->i_disksize in favour of using i_size
everywhere now that the two sizes are always identical.

Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
parent 2422084a

fs/gfs2/aops.c

+4 −6
Original line number Diff line number Diff line
@@ -696,13 +696,11 @@ out: 


	page_cache_release(page);



	/*

	 * XXX(truncate): the call below should probably be replaced with

	 * a call to the gfs2-specific truncate blocks helper to actually

	 * release disk blocks..

	 */

	gfs2_trans_end(sdp);

	if (pos + len > ip->i_inode.i_size)

		truncate_setsize(&ip->i_inode, ip->i_inode.i_size);

		gfs2_trim_blocks(&ip->i_inode);

	goto out_trans_fail;



out_endtrans:

	gfs2_trans_end(sdp);

out_trans_fail:

fs/gfs2/bmap.c

+119 −128
Original line number Diff line number Diff line
@@ -50,7 +50,7 @@ struct strip_mine { 
 * @ip: the inode

 * @dibh: the dinode buffer

 * @block: the block number that was allocated

 * @private: any locked page held by the caller process

 * @page: The (optional) page. This is looked up if @page is NULL

 *

 * Returns: errno

 */
@@ -109,8 +109,7 @@ static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh, 
/**

 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big

 * @ip: The GFS2 inode to unstuff

 * @unstuffer: the routine that handles unstuffing a non-zero length file

 * @private: private data for the unstuffer

 * @page: The (optional) page. This is looked up if the @page is NULL

 *

 * This routine unstuffs a dinode and returns it to a "normal" state such

 * that the height can be grown in the traditional way.
@@ -884,84 +883,15 @@ out: 
	return error;

}



/**

 * do_grow - Make a file look bigger than it is

 * @ip: the inode

 * @size: the size to set the file to

 *

 * Called with an exclusive lock on @ip.

 *

 * Returns: errno

 */



static int do_grow(struct gfs2_inode *ip, u64 size)

{

	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);

	struct gfs2_alloc *al;

	struct buffer_head *dibh;

	int error;



	al = gfs2_alloc_get(ip);

	if (!al)

		return -ENOMEM;



	error = gfs2_quota_lock_check(ip);

	if (error)

		goto out;



	al->al_requested = sdp->sd_max_height + RES_DATA;



	error = gfs2_inplace_reserve(ip);

	if (error)

		goto out_gunlock_q;



	error = gfs2_trans_begin(sdp,

			sdp->sd_max_height + al->al_rgd->rd_length +

			RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0);

	if (error)

		goto out_ipres;



	error = gfs2_meta_inode_buffer(ip, &dibh);

	if (error)

		goto out_end_trans;



	if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {

		if (gfs2_is_stuffed(ip)) {

			error = gfs2_unstuff_dinode(ip, NULL);

			if (error)

				goto out_brelse;

		}

	}



	ip->i_disksize = size;

	ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;

	gfs2_trans_add_bh(ip->i_gl, dibh, 1);

	gfs2_dinode_out(ip, dibh->b_data);



out_brelse:

	brelse(dibh);

out_end_trans:

	gfs2_trans_end(sdp);

out_ipres:

	gfs2_inplace_release(ip);

out_gunlock_q:

	gfs2_quota_unlock(ip);

out:

	gfs2_alloc_put(ip);

	return error;

}





/**

 * gfs2_block_truncate_page - Deal with zeroing out data for truncate

 *

 * This is partly borrowed from ext3.

 */

static int gfs2_block_truncate_page(struct address_space *mapping)

static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)

{

	struct inode *inode = mapping->host;

	struct gfs2_inode *ip = GFS2_I(inode);

	loff_t from = inode->i_size;

	unsigned long index = from >> PAGE_CACHE_SHIFT;

	unsigned offset = from & (PAGE_CACHE_SIZE-1);

	unsigned blocksize, iblock, length, pos;
@@ -1023,9 +953,11 @@ unlock: 
	return err;

}



static int trunc_start(struct gfs2_inode *ip, u64 size)

static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize)

{

	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_sbd *sdp = GFS2_SB(inode);

	struct address_space *mapping = inode->i_mapping;

	struct buffer_head *dibh;

	int journaled = gfs2_is_jdata(ip);

	int error;
@@ -1039,31 +971,27 @@ static int trunc_start(struct gfs2_inode *ip, u64 size) 
	if (error)

		goto out;



	if (gfs2_is_stuffed(ip)) {

		u64 dsize = size + sizeof(struct gfs2_dinode);

		ip->i_disksize = size;

		ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;

	gfs2_trans_add_bh(ip->i_gl, dibh, 1);

		gfs2_dinode_out(ip, dibh->b_data);

		if (dsize > dibh->b_size)

			dsize = dibh->b_size;

		gfs2_buffer_clear_tail(dibh, dsize);

		error = 1;



	if (gfs2_is_stuffed(ip)) {

		gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize);

	} else {

		if (size & (u64)(sdp->sd_sb.sb_bsize - 1))

			error = gfs2_block_truncate_page(ip->i_inode.i_mapping);

		if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) {

			error = gfs2_block_truncate_page(mapping, newsize);

			if (error)

				goto out_brelse;

		}

		ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;

	}



		if (!error) {

			ip->i_disksize = size;

	i_size_write(inode, newsize);

	ip->i_disksize = newsize;

	ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;

			ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;

			gfs2_trans_add_bh(ip->i_gl, dibh, 1);

	gfs2_dinode_out(ip, dibh->b_data);

		}

	}



	truncate_pagecache(inode, oldsize, newsize);

out_brelse:

	brelse(dibh);



out:

	gfs2_trans_end(sdp);

	return error;
@@ -1143,86 +1071,149 @@ out: 


/**

 * do_shrink - make a file smaller

 * @ip: the inode

 * @size: the size to make the file

 * @truncator: function to truncate the last partial block

 * @inode: the inode

 * @oldsize: the current inode size

 * @newsize: the size to make the file

 *

 * Called with an exclusive lock on @ip.

 * Called with an exclusive lock on @inode. The @size must

 * be equal to or smaller than the current inode size.

 *

 * Returns: errno

 */



static int do_shrink(struct gfs2_inode *ip, u64 size)

static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize)

{

	struct gfs2_inode *ip = GFS2_I(inode);

	int error;



	error = trunc_start(ip, size);

	error = trunc_start(inode, oldsize, newsize);

	if (error < 0)

		return error;

	if (error > 0)

	if (gfs2_is_stuffed(ip))

		return 0;



	error = trunc_dealloc(ip, size);

	if (!error)

	error = trunc_dealloc(ip, newsize);

	if (error == 0)

		error = trunc_end(ip);



	return error;

}



static int do_touch(struct gfs2_inode *ip, u64 size)

void gfs2_trim_blocks(struct inode *inode)

{

	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);

	u64 size = inode->i_size;

	int ret;



	ret = do_shrink(inode, size, size);

	WARN_ON(ret != 0);

}



/**

 * do_grow - Touch and update inode size

 * @inode: The inode

 * @size: The new size

 *

 * This function updates the timestamps on the inode and

 * may also increase the size of the inode. This function

 * must not be called with @size any smaller than the current

 * inode size.

 *

 * Although it is not strictly required to unstuff files here,

 * earlier versions of GFS2 have a bug in the stuffed file reading

 * code which will result in a buffer overrun if the size is larger

 * than the max stuffed file size. In order to prevent this from

 * occuring, such files are unstuffed, but in other cases we can

 * just update the inode size directly.

 *

 * Returns: 0 on success, or -ve on error

 */



static int do_grow(struct inode *inode, u64 size)

{

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_sbd *sdp = GFS2_SB(inode);

	struct buffer_head *dibh;

	struct gfs2_alloc *al = NULL;

	int error;



	error = gfs2_trans_begin(sdp, RES_DINODE, 0);

	if (gfs2_is_stuffed(ip) &&

	    (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) {

		al = gfs2_alloc_get(ip);

		if (al == NULL)

			return -ENOMEM;



		error = gfs2_quota_lock_check(ip);

		if (error)

		return error;

			goto do_grow_alloc_put;



	down_write(&ip->i_rw_mutex);

		al->al_requested = 1;

		error = gfs2_inplace_reserve(ip);

		if (error)

			goto do_grow_qunlock;

	}



	error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);

	if (error)

		goto do_grow_release;



	if (al) {

		error = gfs2_unstuff_dinode(ip, NULL);

		if (error)

			goto do_end_trans;

	}



	error = gfs2_meta_inode_buffer(ip, &dibh);

	if (error)

		goto do_touch_out;

		goto do_end_trans;



	i_size_write(inode, size);

	ip->i_disksize = size;

	ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;

	gfs2_trans_add_bh(ip->i_gl, dibh, 1);

	gfs2_dinode_out(ip, dibh->b_data);

	brelse(dibh);



do_touch_out:

	up_write(&ip->i_rw_mutex);

do_end_trans:

	gfs2_trans_end(sdp);

do_grow_release:

	if (al) {

		gfs2_inplace_release(ip);

do_grow_qunlock:

		gfs2_quota_unlock(ip);

do_grow_alloc_put:

		gfs2_alloc_put(ip);

	}

	return error;

}



/**

 * gfs2_truncatei - make a file a given size

 * @ip: the inode

 * @size: the size to make the file

 * @truncator: function to truncate the last partial block

 * gfs2_setattr_size - make a file a given size

 * @inode: the inode

 * @newsize: the size to make the file

 *

 * The file size can grow, shrink, or stay the same size.

 * The file size can grow, shrink, or stay the same size. This

 * is called holding i_mutex and an exclusive glock on the inode

 * in question.

 *

 * Returns: errno

 */



int gfs2_truncatei(struct gfs2_inode *ip, u64 size)

int gfs2_setattr_size(struct inode *inode, u64 newsize)

{

	int error;

	int ret;

	u64 oldsize;



	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), S_ISREG(ip->i_inode.i_mode)))

		return -EINVAL;

	BUG_ON(!S_ISREG(inode->i_mode));



	if (size > ip->i_disksize)

		error = do_grow(ip, size);

	else if (size < ip->i_disksize)

		error = do_shrink(ip, size);

	else

		/* update time stamps */

		error = do_touch(ip, size);

	ret = inode_newsize_ok(inode, newsize);

	if (ret)

		return ret;



	return error;

	oldsize = inode->i_size;

	if (newsize >= oldsize)

		return do_grow(inode, newsize);



	return do_shrink(inode, oldsize, newsize);

}



int gfs2_truncatei_resume(struct gfs2_inode *ip)

fs/gfs2/bmap.h

+11 −9
Original line number Diff line number Diff line
@@ -44,14 +44,16 @@ static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip, 
	}

}



int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page);

int gfs2_block_map(struct inode *inode, sector_t lblock, struct buffer_head *bh, int create);

int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen);



int gfs2_truncatei(struct gfs2_inode *ip, u64 size);

int gfs2_truncatei_resume(struct gfs2_inode *ip);

int gfs2_file_dealloc(struct gfs2_inode *ip);

int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,

extern int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page);

extern int gfs2_block_map(struct inode *inode, sector_t lblock,

			  struct buffer_head *bh, int create);

extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new,

			   u64 *dblock, unsigned *extlen);

extern int gfs2_setattr_size(struct inode *inode, u64 size);

extern void gfs2_trim_blocks(struct inode *inode);

extern int gfs2_truncatei_resume(struct gfs2_inode *ip);

extern int gfs2_file_dealloc(struct gfs2_inode *ip);

extern int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,

				     unsigned int len);



#endif /* __BMAP_DOT_H__ */

fs/gfs2/ops_inode.c

+1 −25
Original line number Diff line number Diff line
@@ -1071,30 +1071,6 @@ int gfs2_permission(struct inode *inode, int mask) 
	return error;

}



/*

 * XXX(truncate): the truncate_setsize calls should be moved to the end.

 */

static int setattr_size(struct inode *inode, struct iattr *attr)

{

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_sbd *sdp = GFS2_SB(inode);

	int error;



	if (attr->ia_size != ip->i_disksize) {

		error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);

		if (error)

			return error;

		truncate_setsize(inode, attr->ia_size);

		gfs2_trans_end(sdp);

	}



	error = gfs2_truncatei(ip, attr->ia_size);

	if (error && (inode->i_size != ip->i_disksize))

		i_size_write(inode, ip->i_disksize);



	return error;

}



static int setattr_chown(struct inode *inode, struct iattr *attr)

{

	struct gfs2_inode *ip = GFS2_I(inode);
@@ -1195,7 +1171,7 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr) 
		goto out;



	if (attr->ia_valid & ATTR_SIZE)

		error = setattr_size(inode, attr);

		error = gfs2_setattr_size(inode, attr->ia_size);

	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))

		error = setattr_chown(inode, attr);

	else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))

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