Commit 55f020db authored by Allison Henderson's avatar Allison Henderson Committed by Theodore Ts'o
Browse files

ext4: add flag to ext4_has_free_blocks 



This patch adds an allocation request flag to the ext4_has_free_blocks
function which enables the use of reserved blocks.  This will allow a
punch hole to proceed even if the disk is full.  Punching a hole may
require additional blocks to first split the extents.

Because ext4_has_free_blocks is a low level function, the flag needs
to be passed down through several functions listed below:

ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_ext_split
ext4_ext_new_meta_block
ext4_mb_new_blocks
ext4_claim_free_blocks
ext4_has_free_blocks

[ext4 punch hole patch series 1/5 v7]

Signed-off-by: default avatarAllison Henderson <achender@us.ibm.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: default avatarMingming Cao <cmm@us.ibm.com>
parent ae812306

fs/ext4/balloc.c

+11 −6
Original line number Diff line number Diff line
@@ -369,7 +369,8 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group) 
 * Check if filesystem has nblocks free & available for allocation.

 * On success return 1, return 0 on failure.

 */

static int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks)

static int ext4_has_free_blocks(struct ext4_sb_info *sbi,

				s64 nblocks, unsigned int flags)

{

	s64 free_blocks, dirty_blocks, root_blocks;

	struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
@@ -393,7 +394,9 @@ static int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks) 
	/* Hm, nope.  Are (enough) root reserved blocks available? */

	if (sbi->s_resuid == current_fsuid() ||

	    ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||

	    capable(CAP_SYS_RESOURCE)) {

	    capable(CAP_SYS_RESOURCE) ||

		(flags & EXT4_MB_USE_ROOT_BLOCKS)) {



		if (free_blocks >= (nblocks + dirty_blocks))

			return 1;

	}
@@ -402,9 +405,9 @@ static int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks) 
}



int ext4_claim_free_blocks(struct ext4_sb_info *sbi,

						s64 nblocks)

			   s64 nblocks, unsigned int flags)

{

	if (ext4_has_free_blocks(sbi, nblocks)) {

	if (ext4_has_free_blocks(sbi, nblocks, flags)) {

		percpu_counter_add(&sbi->s_dirtyblocks_counter, nblocks);

		return 0;

	} else
@@ -425,7 +428,7 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi, 
 */

int ext4_should_retry_alloc(struct super_block *sb, int *retries)

{

	if (!ext4_has_free_blocks(EXT4_SB(sb), 1) ||

	if (!ext4_has_free_blocks(EXT4_SB(sb), 1, 0) ||

	    (*retries)++ > 3 ||

	    !EXT4_SB(sb)->s_journal)

		return 0;
@@ -448,7 +451,8 @@ int ext4_should_retry_alloc(struct super_block *sb, int *retries) 
 * error stores in errp pointer

 */

ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,

		ext4_fsblk_t goal, unsigned long *count, int *errp)

				  ext4_fsblk_t goal, unsigned int flags,

				  unsigned long *count, int *errp)

{

	struct ext4_allocation_request ar;

	ext4_fsblk_t ret;
@@ -458,6 +462,7 @@ ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, 
	ar.inode = inode;

	ar.goal = goal;

	ar.len = count ? *count : 1;

	ar.flags = flags;



	ret = ext4_mb_new_blocks(handle, &ar, errp);

	if (count)

fs/ext4/ext4.h

+10 −3
Original line number Diff line number Diff line
@@ -108,7 +108,8 @@ typedef unsigned int ext4_group_t; 
#define EXT4_MB_DELALLOC_RESERVED	0x0400

/* We are doing stream allocation */

#define EXT4_MB_STREAM_ALLOC		0x0800



/* Use reserved root blocks if needed */

#define EXT4_MB_USE_ROOT_BLOCKS		0x1000



struct ext4_allocation_request {

	/* target inode for block we're allocating */
@@ -514,6 +515,8 @@ struct ext4_new_group_data { 
	/* Convert extent to initialized after IO complete */

#define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\

					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)

	/* Punch out blocks of an extent */

#define EXT4_GET_BLOCKS_PUNCH_OUT_EXT		0x0020



/*

 * Flags used by ext4_free_blocks
@@ -1718,8 +1721,12 @@ extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group); 
extern unsigned long ext4_bg_num_gdb(struct super_block *sb,

			ext4_group_t group);

extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,

			ext4_fsblk_t goal, unsigned long *count, int *errp);

extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);

					 ext4_fsblk_t goal,

					 unsigned int flags,

					 unsigned long *count,

					 int *errp);

extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,

				  s64 nblocks, unsigned int flags);

extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);

extern void ext4_check_blocks_bitmap(struct super_block *);

extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,

fs/ext4/extents.c

+22 −13
Original line number Diff line number Diff line
@@ -192,12 +192,13 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode, 
static ext4_fsblk_t

ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,

			struct ext4_ext_path *path,

			struct ext4_extent *ex, int *err)

			struct ext4_extent *ex, int *err, unsigned int flags)

{

	ext4_fsblk_t goal, newblock;



	goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));

	newblock = ext4_new_meta_blocks(handle, inode, goal, NULL, err);

	newblock = ext4_new_meta_blocks(handle, inode, goal, flags,

					NULL, err);

	return newblock;

}
@@ -792,6 +793,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, 
 * - initializes subtree

 */

static int ext4_ext_split(handle_t *handle, struct inode *inode,

			  unsigned int flags,

			  struct ext4_ext_path *path,

			  struct ext4_extent *newext, int at)

{
@@ -847,7 +849,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode, 
	ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);

	for (a = 0; a < depth - at; a++) {

		newblock = ext4_ext_new_meta_block(handle, inode, path,

						   newext, &err);

						   newext, &err, flags);

		if (newblock == 0)

			goto cleanup;

		ablocks[a] = newblock;
@@ -1056,6 +1058,7 @@ cleanup: 
 *   just created block

 */

static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,

				 unsigned int flags,

				 struct ext4_ext_path *path,

				 struct ext4_extent *newext)

{
@@ -1065,7 +1068,8 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode, 
	ext4_fsblk_t newblock;

	int err = 0;



	newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);

	newblock = ext4_ext_new_meta_block(handle, inode, path,

		newext, &err, flags);

	if (newblock == 0)

		return err;
@@ -1140,6 +1144,7 @@ out: 
 * if no free index is found, then it requests in-depth growing.

 */

static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,

				    unsigned int flags,

				    struct ext4_ext_path *path,

				    struct ext4_extent *newext)

{
@@ -1161,7 +1166,7 @@ repeat: 
	if (EXT_HAS_FREE_INDEX(curp)) {

		/* if we found index with free entry, then use that

		 * entry: create all needed subtree and add new leaf */

		err = ext4_ext_split(handle, inode, path, newext, i);

		err = ext4_ext_split(handle, inode, flags, path, newext, i);

		if (err)

			goto out;
@@ -1174,7 +1179,8 @@ repeat: 
			err = PTR_ERR(path);

	} else {

		/* tree is full, time to grow in depth */

		err = ext4_ext_grow_indepth(handle, inode, path, newext);

		err = ext4_ext_grow_indepth(handle, inode, flags,

					    path, newext);

		if (err)

			goto out;
@@ -1693,6 +1699,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, 
	int depth, len, err;

	ext4_lblk_t next;

	unsigned uninitialized = 0;

	int flags = 0;



	if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {

		EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
@@ -1767,7 +1774,9 @@ repeat: 
	 * There is no free space in the found leaf.

	 * We're gonna add a new leaf in the tree.

	 */

	err = ext4_ext_create_new_leaf(handle, inode, path, newext);

	if (flag & EXT4_GET_BLOCKS_PUNCH_OUT_EXT)

		flags = EXT4_MB_USE_ROOT_BLOCKS;

	err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);

	if (err)

		goto cleanup;

	depth = ext_depth(inode);

fs/ext4/inode.c

+3 −3
Original line number Diff line number Diff line
@@ -639,8 +639,8 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, 
	while (target > 0) {

		count = target;

		/* allocating blocks for indirect blocks and direct blocks */

		current_block = ext4_new_meta_blocks(handle, inode,

							goal, &count, err);

		current_block = ext4_new_meta_blocks(handle, inode, goal,

						     0, &count, err);

		if (*err)

			goto failed_out;
@@ -1930,7 +1930,7 @@ repeat: 
	 * We do still charge estimated metadata to the sb though;

	 * we cannot afford to run out of free blocks.

	 */

	if (ext4_claim_free_blocks(sbi, md_needed + 1)) {

	if (ext4_claim_free_blocks(sbi, md_needed + 1, 0)) {

		dquot_release_reservation_block(inode, 1);

		if (ext4_should_retry_alloc(inode->i_sb, &retries)) {

			yield();

fs/ext4/mballoc.c

+12 −4
Original line number Diff line number Diff line
@@ -4236,7 +4236,9 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, 
		 * there is enough free blocks to do block allocation

		 * and verify allocation doesn't exceed the quota limits.

		 */

		while (ar->len && ext4_claim_free_blocks(sbi, ar->len)) {

		while (ar->len &&

			ext4_claim_free_blocks(sbi, ar->len, ar->flags)) {



			/* let others to free the space */

			yield();

			ar->len = ar->len >> 1;
@@ -4246,10 +4248,16 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, 
			return 0;

		}

		reserv_blks = ar->len;

		while (ar->len && dquot_alloc_block(ar->inode, ar->len)) {

		if (ar->flags & EXT4_MB_USE_ROOT_BLOCKS) {

			dquot_alloc_block_nofail(ar->inode, ar->len);

		} else {

			while (ar->len &&

				dquot_alloc_block(ar->inode, ar->len)) {



				ar->flags |= EXT4_MB_HINT_NOPREALLOC;

				ar->len--;

			}

		}

		inquota = ar->len;

		if (ar->len == 0) {

			*errp = -EDQUOT;

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