From: Mingming Cao Subject: Re: [Ext4 punch hole 1/5 v7] Ext4 Punch Hole Support: Add flag to ext4_has_free_blocks Date: Mon, 09 May 2011 17:46:36 -0700 Message-ID: <1304988396.2543.1.camel@mingming-laptop> References: <4DC5DB94.8060300@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Ext4 Developers List To: Allison Henderson Return-path: Received: from e35.co.us.ibm.com ([32.97.110.153]:49407 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753625Ab1EJAqm (ORCPT ); Mon, 9 May 2011 20:46:42 -0400 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e35.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p4A0To1f006336 for ; Mon, 9 May 2011 18:29:50 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id p4A0kcl8158128 for ; Mon, 9 May 2011 18:46:38 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p49IkADo031315 for ; Mon, 9 May 2011 12:46:10 -0600 In-Reply-To: <4DC5DB94.8060300@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sat, 2011-05-07 at 16:53 -0700, Allison Henderson wrote: > 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 > > Signed-off-by: Allison Henderson Looks fine with me. You could add: Reviewed-by: Mingming Cao > --- > :100644 100644 9c6cd51... 32003c2... M fs/ext4/balloc.c > :100644 100644 076c5d2... 3ba6c31... M fs/ext4/ext4.h > :100644 100644 e363f21... e04faeb... M fs/ext4/extents.c > :100644 100644 f2fa5e8... f92c58b... M fs/ext4/inode.c > :100644 100644 730c1a7... 85cc3ef... M fs/ext4/mballoc.c > :100644 100644 b545ca1... 2d9b12c... M fs/ext4/xattr.c > fs/ext4/balloc.c | 17 +++++++++++------ > fs/ext4/ext4.h | 11 ++++++++--- > fs/ext4/extents.c | 30 ++++++++++++++++++++---------- > fs/ext4/inode.c | 4 ++-- > fs/ext4/mballoc.c | 16 ++++++++++++---- > fs/ext4/xattr.c | 2 +- > 6 files changed, 54 insertions(+), 26 deletions(-) > > diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c > index 9c6cd51..32003c2 100644 > --- a/fs/ext4/balloc.c > +++ b/fs/ext4/balloc.c > @@ -493,7 +493,8 @@ error_return: > * 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; > @@ -517,7 +518,9 @@ 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; > } > @@ -526,9 +529,9 @@ 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 > @@ -549,7 +552,7 @@ 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; > @@ -572,7 +575,8 @@ 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 long *count, int *errp, > + unsigned int flags) > { > struct ext4_allocation_request ar; > ext4_fsblk_t ret; > @@ -582,6 +586,7 @@ 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) > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > index 076c5d2..3ba6c31 100644 > --- a/fs/ext4/ext4.h > +++ b/fs/ext4/ext4.h > @@ -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 */ > @@ -512,6 +513,8 @@ 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 > @@ -1653,8 +1656,10 @@ 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 long *count, > + int *errp, unsigned int flags); > +extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, > + s64 nblocks, unsigned int flags); > extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb, > ext4_fsblk_t block, unsigned long count); > extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *); > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > index e363f21..e04faeb 100644 > --- a/fs/ext4/extents.c > +++ b/fs/ext4/extents.c > @@ -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, > + NULL, err, flags); > return newblock; > } > > @@ -793,7 +794,8 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, > */ > static int ext4_ext_split(handle_t *handle, struct inode *inode, > struct ext4_ext_path *path, > - struct ext4_extent *newext, int at) > + struct ext4_extent *newext, int at, > + unsigned int flags) > { > struct buffer_head *bh = NULL; > int depth = ext_depth(inode); > @@ -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; > @@ -1057,7 +1059,8 @@ cleanup: > */ > static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode, > struct ext4_ext_path *path, > - struct ext4_extent *newext) > + struct ext4_extent *newext, > + unsigned int flags) > { > struct ext4_ext_path *curp = path; > struct ext4_extent_header *neh; > @@ -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; > > @@ -1141,7 +1145,8 @@ out: > */ > static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode, > struct ext4_ext_path *path, > - struct ext4_extent *newext) > + struct ext4_extent *newext, > + unsigned int flags) > { > struct ext4_ext_path *curp; > int depth, i, err = 0; > @@ -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, path, newext, i, flags); > 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, path, > + newext, flags); > 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 +1774,10 @@ 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, path, > + newext, flags); > if (err) > goto cleanup; > depth = ext_depth(inode); > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index f2fa5e8..f92c58b 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -640,7 +640,7 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, > count = target; > /* allocating blocks for indirect blocks and direct blocks */ > current_block = ext4_new_meta_blocks(handle, inode, > - goal, &count, err); > + goal, &count, err, 0); > 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(); > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index 730c1a7..85cc3ef 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -4299,7 +4299,9 @@ 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; > @@ -4309,9 +4311,15 @@ 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)) { > - ar->flags |= EXT4_MB_HINT_NOPREALLOC; > - 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) { > diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c > index b545ca1..2d9b12c 100644 > --- a/fs/ext4/xattr.c > +++ b/fs/ext4/xattr.c > @@ -821,7 +821,7 @@ inserted: > goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; > > block = ext4_new_meta_blocks(handle, inode, > - goal, NULL, &error); > + goal, NULL, &error, 0); > if (error) > goto cleanup; >