From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([59.151.112.132]:35031 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751445AbbJNHTU (ORCPT ); Wed, 14 Oct 2015 03:19:20 -0400 Subject: Re: [PATCH v3 1/2] btrfs: Add support to do stack item key operation To: , David Sterba References: <1444180140-9422-1-git-send-email-quwenruo@cn.fujitsu.com> <561473EF.9060707@cn.fujitsu.com> CC: Chris Mason From: Qu Wenruo Message-ID: <561E01F1.7080802@cn.fujitsu.com> Date: Wed, 14 Oct 2015 15:19:13 +0800 MIME-Version: 1.0 In-Reply-To: <561473EF.9060707@cn.fujitsu.com> Content-Type: text/plain; charset="utf-8"; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi David, Any further comment? Thanks, Qu Qu Wenruo wrote on 2015/10/07 09:22 +0800: > Hi David, > > I'm sorry that I didn't get the point of your previous comment. > > Maybe the parameter/function name don't follow BTRFS_STACK_GETSET_FUNC > macro, but IMHO that's OK, as btrfs_item_key_to_cpu() is not an accessor > following that macro definition. > It's called even before we get needed data structure, so I think the > declaration should be OK. > > BTW, I really hope the fix can be merged before v4.3, as such fix is > quite small, while the bug itself impacts qgroup quite a lot. > > Thanks, > Qu > > Qu Wenruo wrote on 2015/10/07 09:08 +0800: >> Normal btrfs_item_key_to_cpu() will need extent buffer to do it, and >> there is not stack version to handle in memory leaf. >> >> Add btrfs_stack_item_key_to_cpu() function for such operation, which >> will provide the basis for later qgroup fix. >> >> Signed-off-by: Qu Wenruo >> --- >> v2: >> Change the char* parameter to struct btrfs_header *, as a leaf always >> has a header. >> v3: >> Fix a bug caused in type change of stack_leaf. >> --- >> fs/btrfs/ctree.h | 20 ++++++++++++++++++++ >> 1 file changed, 20 insertions(+) >> >> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h >> index 938efe3..b824fe2 100644 >> --- a/fs/btrfs/ctree.h >> +++ b/fs/btrfs/ctree.h >> @@ -2683,6 +2683,17 @@ static inline void btrfs_item_key(struct >> extent_buffer *eb, >> read_eb_member(eb, item, struct btrfs_item, key, disk_key); >> } >> >> +static inline void btrfs_stack_item_key(struct btrfs_header *stack_leaf, >> + struct btrfs_disk_key *disk_key, >> + int nr) >> +{ >> + unsigned long item_offset = btrfs_item_nr_offset(nr); >> + struct btrfs_item *item; >> + >> + item = (struct btrfs_item *)((char *)(stack_leaf) + item_offset); >> + memcpy(disk_key, &item->key, sizeof(*disk_key)); >> +} >> + >> static inline void btrfs_set_item_key(struct extent_buffer *eb, >> struct btrfs_disk_key *disk_key, int nr) >> { >> @@ -2785,6 +2796,15 @@ static inline void btrfs_item_key_to_cpu(struct >> extent_buffer *eb, >> btrfs_disk_key_to_cpu(key, &disk_key); >> } >> >> +static inline void btrfs_stack_item_key_to_cpu(struct btrfs_header >> *stack_leaf, >> + struct btrfs_key *key, >> + int nr) >> +{ >> + struct btrfs_disk_key disk_key; >> + btrfs_stack_item_key(stack_leaf, &disk_key, nr); >> + btrfs_disk_key_to_cpu(key, &disk_key); >> +} >> + >> static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb, >> struct btrfs_dir_item *item, >> struct btrfs_key *key) >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html