From: Mingming Cao <cmm@us.ibm.com>
To: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>, tytso <tytso@mit.edu>,
linux-ext4 <linux-ext4@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH V3 3/3]ext4: quota handling for delayed allocation
Date: Fri, 12 Dec 2008 12:27:53 -0800 [thread overview]
Message-ID: <1229113673.7646.11.camel@mingming-laptop> (raw)
In-Reply-To: <20081203201105.GE12803@duck.suse.cz>
在 2008-12-03三的 21:11 +0100，Jan Kara写道：
> Hi,
>
> On Thu 06-11-08 15:39:05, Mingming Cao wrote:
> > ext4: quota reservation for delayed allocation
> >
> > Uses quota reservation/claim/release to handle quota properly for delayed
> > allocation in the three steps: 1) quotas are reserved when data being copied
> > to cache when block allocation is defered 2) when new blocks are allocated.
> > reserved quotas are converted to the real allocated quota, 2) over-booked
> > quotas for metadata blocks are released back.
> >
> >
> > Signed-off-by: Mingming Cao <cmm@us.ibm.com>
> > ---
> > fs/ext4/inode.c | 29 ++++++++++++++++++++++++++---
> > fs/ext4/mballoc.c | 42 +++++++++++++++++++++++++-----------------
> > fs/ext4/super.c | 3 +++
> > 3 files changed, 54 insertions(+), 20 deletions(-)
> >
> > Index: linux-2.6.28-rc2/fs/ext4/inode.c
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/fs/ext4/inode.c 2008-11-06 13:36:16.000000000 -0800
> > +++ linux-2.6.28-rc2/fs/ext4/inode.c 2008-11-06 14:03:35.000000000 -0800
> > @@ -994,7 +994,9 @@ static void ext4_da_update_reserve_space
> > {
> > struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> > int total, mdb, mdb_free;
> > + int claim_quota, free_quota = 0;
> >
> > + claim_quota = used;
> > spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
> > /* recalculate the number of metablocks still need to be reserved */
> > total = EXT4_I(inode)->i_reserved_data_blocks - used;
> > @@ -1007,6 +1009,8 @@ static void ext4_da_update_reserve_space
> > if (mdb_free) {
> > /* Account for allocated meta_blocks */
> > mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
> > + free_quota = mdb_free;
> > + claim_quota += EXT4_I(inode)->i_allocated_meta_blocks;
> >
> > /* update fs dirty blocks counter */
> > percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free);
> > @@ -1017,8 +1021,14 @@ static void ext4_da_update_reserve_space
> > /* update per-inode reservations */
> > BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks);
> > EXT4_I(inode)->i_reserved_data_blocks -= used;
> > -
> > spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
> > +
> > + /*
> > + * free those over-booking quota for metadata blocks
> > + */
> > +
> > + if (free_quota)
> > + DQUOT_RELEASE_RSV_BLOCK(inode, free_quota);
> claim_quota seems to be unused here and I'm not sure we need it for
> anything...
>
> > }
> >
> > /*
> > @@ -1514,8 +1524,8 @@ static int ext4_journalled_write_end(str
> > static int ext4_da_reserve_space(struct inode *inode, int nrblocks)
> > {
> > int retries = 0;
> > - struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> > - unsigned long md_needed, mdblocks, total = 0;
> > + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> > + unsigned long md_needed, mdblocks, total = 0;
> >
> > /*
> > * recalculate the amount of metadata blocks to reserve
> > @@ -1531,12 +1541,23 @@ repeat:
> > md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks;
> > total = md_needed + nrblocks;
> >
> > + /*
> > + * Make quota reservation here to prevent quota overflow
> > + * later. Real quota accounting is done at pages writeout
> > + * time.
> > + */
> > + if (DQUOT_RESERVE_BLOCK(inode, total)) {
> > + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
> > + return -EDQUOT;
> > + }
> > +
> > if (ext4_claim_free_blocks(sbi, total)) {
> > spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
> > if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
> > yield();
> > goto repeat;
> > }
> > + DQUOT_RELEASE_RSV_BLOCK(inode, total);
> > return -ENOSPC;
> > }
> > EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
> > @@ -1590,6 +1611,8 @@ static void ext4_da_release_space(struct
> > BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
> > EXT4_I(inode)->i_reserved_meta_blocks = mdb;
> > spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
> > +
> > + DQUOT_RELEASE_RSV_BLOCK(inode, release);
> > }
> >
> > static void ext4_da_page_release_reservation(struct page *page,
> > Index: linux-2.6.28-rc2/fs/ext4/super.c
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/fs/ext4/super.c 2008-11-06 13:36:16.000000000 -0800
> > +++ linux-2.6.28-rc2/fs/ext4/super.c 2008-11-06 14:02:57.000000000 -0800
> > @@ -795,6 +795,9 @@ static struct dquot_operations ext4_quot
> > .initialize = ext4_dquot_initialize,
> > .drop = ext4_dquot_drop,
> > .alloc_space = dquot_alloc_space,
> > + .reserve_space = dquot_reserve_space,
> > + .claim_space = dquot_claim_space,
> > + .release_rsv = dquot_release_reserved_space,
> > .alloc_inode = dquot_alloc_inode,
> > .free_space = dquot_free_space,
> > .free_inode = dquot_free_inode,
> > Index: linux-2.6.28-rc2/fs/ext4/mballoc.c
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/fs/ext4/mballoc.c 2008-11-06 13:36:16.000000000 -0800
> > +++ linux-2.6.28-rc2/fs/ext4/mballoc.c 2008-11-06 14:03:35.000000000 -0800
> > @@ -2887,9 +2887,11 @@ ext4_mb_mark_diskspace_used(struct ext4_
> > if (!(ac->ac_flags & EXT4_MB_DELALLOC_RESERVED))
> > /* release all the reserved blocks if non delalloc */
> > percpu_counter_sub(&sbi->s_dirtyblocks_counter, reserv_blks);
> > - else
> > + else {
> > percpu_counter_sub(&sbi->s_dirtyblocks_counter,
> > ac->ac_b_ex.fe_len);
> > + DQUOT_CLAIM_BLOCK(ac->ac_inode, ac->ac_b_ex.fe_len);
> > + }
> >
> > if (sbi->s_log_groups_per_flex) {
> > ext4_group_t flex_group = ext4_flex_group(sbi,
> > @@ -4286,15 +4288,24 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t
> > struct ext4_sb_info *sbi;
> > struct super_block *sb;
> > ext4_fsblk_t block = 0;
> > - unsigned long inquota;
> > + unsigned long inquota = 0;
> > unsigned long reserv_blks = 0;
> >
> > sb = ar->inode->i_sb;
> > sbi = EXT4_SB(sb);
> >
> > - if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag) {
> > + /*
> > + * For delayed allocation, we could skip the ENOSPC and
> > + * EDQUOT check, as blocks and quotas have been already
> > + * reserved when data being copied into pagecache.
> > + */
> > + if (EXT4_I(ar->inode)->i_delalloc_reserved_flag)
> > + ar->flags |= EXT4_MB_DELALLOC_RESERVED;
> > + else {
> > /*
> > - * With delalloc we already reserved the blocks
> > + * Without delayed allocation we need to verify
> > + * 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)) {
> > /* let others to free the space */
> > @@ -4306,19 +4317,16 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t
> > 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->len == 0) {
> > + *errp = -EDQUOT;
> > + return 0;
> > + }
> > + inquota = ar->len;
> > }
> > - while (ar->len && DQUOT_ALLOC_BLOCK(ar->inode, ar->len)) {
> > - ar->flags |= EXT4_MB_HINT_NOPREALLOC;
> > - ar->len--;
> > - }
> > - if (ar->len == 0) {
> > - *errp = -EDQUOT;
> > - return 0;
> > - }
> > - inquota = ar->len;
> > -
> > - if (EXT4_I(ar->inode)->i_delalloc_reserved_flag)
> > - ar->flags |= EXT4_MB_DELALLOC_RESERVED;
> >
> > ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
> > if (!ac) {
> > @@ -4380,7 +4388,7 @@ repeat:
> > out2:
> > kmem_cache_free(ext4_ac_cachep, ac);
> > out1:
> > - if (ar->len < inquota)
> > + if (inquota && ar->len < inquota)
> > DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len);
> >
> > return block;
> >
> Honza
> >
>
incremental fix.
Thanks,
---
fs/ext4/inode.c | 14 +++++---------
fs/ext4/mballoc.c | 3 ++-
2 files changed, 7 insertions(+), 10 deletions(-)
Index: linux-2.6.28-rc2/fs/ext4/inode.c
===================================================================
--- linux-2.6.28-rc2.orig/fs/ext4/inode.c 2008-12-09 17:20:10.000000000 -0800
+++ linux-2.6.28-rc2/fs/ext4/inode.c 2008-12-09 17:35:32.000000000 -0800
@@ -994,9 +994,7 @@ static void ext4_da_update_reserve_space
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
int total, mdb, mdb_free;
- int claim_quota, free_quota = 0;
- claim_quota = used;
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
/* recalculate the number of metablocks still need to be reserved */
total = EXT4_I(inode)->i_reserved_data_blocks - used;
@@ -1009,8 +1007,6 @@ static void ext4_da_update_reserve_space
if (mdb_free) {
/* Account for allocated meta_blocks */
mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
- free_quota = mdb_free;
- claim_quota += EXT4_I(inode)->i_allocated_meta_blocks;
/* update fs dirty blocks counter */
percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free);
@@ -1027,8 +1023,8 @@ static void ext4_da_update_reserve_space
* free those over-booking quota for metadata blocks
*/
- if (free_quota)
- DQUOT_RELEASE_RSV_BLOCK(inode, free_quota);
+ if (mdb_free)
+ vfs_dq_release_reservation_block(inode, mdb_free);
}
/*
@@ -1546,7 +1542,7 @@ repeat:
* later. Real quota accounting is done at pages writeout
* time.
*/
- if (DQUOT_RESERVE_BLOCK(inode, total)) {
+ if (vfs_dq_reserve_block(inode, total)) {
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
return -EDQUOT;
}
@@ -1557,7 +1553,7 @@ repeat:
yield();
goto repeat;
}
- DQUOT_RELEASE_RSV_BLOCK(inode, total);
+ vfs_dq_release_reservation_block(inode, total);
return -ENOSPC;
}
EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
@@ -1612,7 +1608,7 @@ static void ext4_da_release_space(struct
EXT4_I(inode)->i_reserved_meta_blocks = mdb;
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
- DQUOT_RELEASE_RSV_BLOCK(inode, release);
+ vfs_dq_release_reservation_block(inode, release);
}
static void ext4_da_page_release_reservation(struct page *page,
Index: linux-2.6.28-rc2/fs/ext4/mballoc.c
===================================================================
--- linux-2.6.28-rc2.orig/fs/ext4/mballoc.c 2008-12-09 17:20:21.000000000 -0800
+++ linux-2.6.28-rc2/fs/ext4/mballoc.c 2008-12-09 17:22:41.000000000 -0800
@@ -2890,7 +2890,8 @@ ext4_mb_mark_diskspace_used(struct ext4_
else {
percpu_counter_sub(&sbi->s_dirtyblocks_counter,
ac->ac_b_ex.fe_len);
- DQUOT_CLAIM_BLOCK(ac->ac_inode, ac->ac_b_ex.fe_len);
+ /* convert reserved quota blocks to real quota blocks */
+ vfs_dq_claim_block(ac->ac_inode, ac->ac_b_ex.fe_len);
}
if (sbi->s_log_groups_per_flex) {
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
prev parent reply other threads:[~2008-12-12 20:27 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-06 23:39 [PATCH V3 3/3]ext4: quota handling for delayed allocation Mingming Cao
2008-12-03 20:11 ` Jan Kara
2008-12-09 1:50 ` Mingming Cao
2008-12-12 20:27 ` Mingming Cao [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1229113673.7646.11.camel@mingming-laptop \
--to=cmm@us.ibm.com \
--cc=akpm@linux-foundation.org \
--cc=jack@suse.cz \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=tytso@mit.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.