From: jiayingz@google.com (Jiaying Zhang) Subject: [PATCH, RFC] support discard in non-journal ext4 Date: Wed, 12 May 2010 22:00:14 -0700 (PDT) Message-ID: <20100513050014.879651BC316@ruihe.smo.corp.google.com> Cc: jiayingz@google.com To: linux-ext4@vger.kernel.org Return-path: Received: from smtp-out.google.com ([216.239.44.51]:25248 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038Ab0EMFAU (ORCPT ); Thu, 13 May 2010 01:00:20 -0400 Received: from hpaq3.eem.corp.google.com (hpaq3.eem.corp.google.com [172.25.149.3]) by smtp-out.google.com with ESMTP id o4D50ICI031445 for ; Wed, 12 May 2010 22:00:19 -0700 Sender: linux-ext4-owner@vger.kernel.org List-ID: This patch issues discard request for freed blocks in ext4_free_blocks() if ext4 is mounted with discard option and without journal. Author: Jiaying Zhang Date: Wed May 12 21:11:46 2010 -0700 Issue discard request in ext4_free_blocks() when ext4 has no journal and is mounted with discard option. Signed-off-by: Jiaying Zhang diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index a291cc3..d51b79a 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2513,6 +2513,22 @@ int ext4_mb_release(struct super_block *sb) return 0; } +static void ext4_issue_discard(struct super_block *sb, ext4_group_t block_group, + ext4_grpblk_t block, int count) +{ + int ret; + ext4_fsblk_t discard_block; + + discard_block = block + ext4_group_first_block_no(sb, block_group); + trace_ext4_discard_blocks(sb, + (unsigned long long) discard_block, count); + ret = sb_issue_discard(sb, discard_block, count); + if (ret == EOPNOTSUPP) { + ext4_warning(sb, "discard not supported, disabling"); + clear_opt(EXT4_SB(sb)->s_mount_opt, DISCARD); + } +} + /* * This function is called by the jbd2 layer once the commit has finished, * so we know we can free the blocks that were released with that commit. @@ -2532,22 +2548,9 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) mb_debug(1, "gonna free %u blocks in group %u (0x%p):", entry->count, entry->group, entry); - if (test_opt(sb, DISCARD)) { - int ret; - ext4_fsblk_t discard_block; - - discard_block = entry->start_blk + - ext4_group_first_block_no(sb, entry->group); - trace_ext4_discard_blocks(sb, - (unsigned long long)discard_block, - entry->count); - ret = sb_issue_discard(sb, discard_block, entry->count); - if (ret == EOPNOTSUPP) { - ext4_warning(sb, - "discard not supported, disabling"); - clear_opt(EXT4_SB(sb)->s_mount_opt, DISCARD); - } - } + if (test_opt(sb, DISCARD)) + ext4_issue_discard(sb, entry->group, + entry->start_blk, entry->count); err = ext4_mb_load_buddy(sb, entry->group, &e4b); /* we expect to find existing buddy because it's pinned */ @@ -4600,6 +4603,8 @@ do_more: mb_clear_bits(bitmap_bh->b_data, bit, count); mb_free_blocks(inode, &e4b, bit, count); ext4_mb_return_to_preallocation(inode, &e4b, block, count); + if (test_opt(sb, DISCARD)) + ext4_issue_discard(sb, block_group, bit, count); } ret = ext4_free_blks_count(sb, gdp) + count;