lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [day] [month] [year] [list]
Date:	Wed, 29 Oct 2008 17:59:23 -0700
From:	Mingming Cao <cmm@...ibm.com>
To:	Jan Kara <jack@...e.cz>
Cc:	linux-ext4 <linux-ext4@...r.kernel.org>, tytso <tytso@....edu>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>
Subject: [RFC PATCH 3/3] ext4: quota handling for delayed allocation

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@...ibm.com>
---
 fs/ext4/inode.c   |   25 ++++++++++++++++++++++++-
 fs/ext4/mballoc.c |   18 +++++++++---------
 fs/ext4/super.c   |    2 ++
 3 files changed, 35 insertions(+), 10 deletions(-)

Index: linux-2.6.28-rc2/fs/ext4/inode.c
===================================================================
--- linux-2.6.28-rc2.orig/fs/ext4/inode.c	2008-10-26 12:13:29.000000000 -0700
+++ linux-2.6.28-rc2/fs/ext4/inode.c	2008-10-28 17:38:07.000000000 -0700
@@ -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);
 }
 
 /*
@@ -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	2008-10-28 16:01:42.000000000 -0700
+++ linux-2.6.28-rc2/fs/ext4/super.c	2008-10-28 17:38:07.000000000 -0700
@@ -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	2008-10-28 16:00:53.000000000 -0700
+++ linux-2.6.28-rc2/fs/ext4/mballoc.c	2008-10-28 17:38:07.000000000 -0700
@@ -2887,9 +2887,12 @@ 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);
+		printk("allocatin %d blocks, charged to quota\n", ac->ac_b_ex.fe_len);
+	}
 
 	if (sbi->s_log_groups_per_flex) {
 		ext4_group_t flex_group = ext4_flex_group(sbi,
@@ -4306,14 +4309,14 @@ 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;
+		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;
 
@@ -4380,7 +4383,7 @@ 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;



--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ