From: Eric Sandeen Date: Mon, 31 May 2010 02:49:51 +0000 (-0400) Subject: ext4: stop issuing discards if not supported by device X-Git-Tag: firefly_0821_release~10186^2~1316 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7a5fb6dc311ddb933e8299cb89fab289bc846c9b;p=firefly-linux-kernel-4.4.55.git ext4: stop issuing discards if not supported by device commit a30eec2a8650a77f754e84b2e15f062fe652baa7 upstream (as of v2.6.34-git13) Turn off issuance of discard requests if the device does not support it - similar to the action we take for barriers. This will save a little computation time if a non-discardable device is mounted with -o discard, and also makes it obvious that it's not doing what was asked at mount time ... Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 6c59921dac72..43d84b7df13f 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2536,6 +2536,7 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) entry->count, entry->group, entry); if (test_opt(sb, DISCARD)) { + int ret; ext4_fsblk_t discard_block; discard_block = entry->start_blk + @@ -2543,7 +2544,12 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) trace_ext4_discard_blocks(sb, (unsigned long long)discard_block, entry->count); - sb_issue_discard(sb, discard_block, entry->count); + ret = sb_issue_discard(sb, discard_block, entry->count); + if (ret == EOPNOTSUPP) { + ext4_warning(sb, __func__, + "discard not supported, disabling"); + clear_opt(EXT4_SB(sb)->s_mount_opt, DISCARD); + } } err = ext4_mb_load_buddy(sb, entry->group, &e4b);