From: Anand Jain <anand.jain@oracle.com>
To: Qu Wenruo <quwenruo@cn.fujitsu.com>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH v3.1 1/7] btrfs: Introduce a function to check if all chunks a OK for degraded rw mount
Date: Mon, 13 Mar 2017 15:29:06 +0800 [thread overview]
Message-ID: <f01fd9f3-85fe-c390-5358-be8c5d67ebc6@oracle.com> (raw)
In-Reply-To: <20170309013442.19957-2-quwenruo@cn.fujitsu.com>
On 03/09/2017 09:34 AM, Qu Wenruo wrote:
> Introduce a new function, btrfs_check_rw_degradable(), to check if all
> chunks in btrfs is OK for degraded rw mount.
>
> It provides the new basis for accurate btrfs mount/remount and even
> runtime degraded mount check other than old one-size-fit-all method.
>
> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> Tested-by: Austin S. Hemmelgarn <ahferroin7@gmail.com>
> Tested-by: Adam Borowski <kilobyte@angband.pl>
> Tested-by: Dmitrii Tcvetkov <demfloro@demfloro.ru>
> ---
> fs/btrfs/volumes.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> fs/btrfs/volumes.h | 1 +
> 2 files changed, 56 insertions(+)
>
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 73d56eef5e60..83613955e3c2 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -6765,6 +6765,61 @@ int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
> return -EIO;
> }
>
> +/*
> + * Check if all chunks in the fs is OK for read-write degraded mount
> + *
> + * Return true if the fs is OK to be mounted degraded read-write
> + * Return false if the fs is not OK to be mounted degraded
> + */
> +bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info)
> +{
> + struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
> + struct extent_map *em;
> + u64 next_start = 0;
> + bool ret = true;
> +
> + read_lock(&map_tree->map_tree.lock);
> + em = lookup_extent_mapping(&map_tree->map_tree, 0, (u64)-1);
> + read_unlock(&map_tree->map_tree.lock);
> + /* No chunk at all? Return false anyway */
> + if (!em) {
> + ret = false;
> + goto out;
> + }
> + while (em) {
> + struct map_lookup *map;
> + int missing = 0;
> + int max_tolerated;
> + int i;
> +
> + map = (struct map_lookup *) em->bdev;
any idea why not map = em->map_lookup; here?
Thanks, Anand
> + max_tolerated =
> + btrfs_get_num_tolerated_disk_barrier_failures(
> + map->type);
> + for (i = 0; i < map->num_stripes; i++) {
> + if (map->stripes[i].dev->missing)
> + missing++;
> + }
> + if (missing > max_tolerated) {
> + ret = false;
> + btrfs_warn(fs_info,
> + "chunk %llu missing %d devices, max tolerance is %d for writeble mount",
> + em->start, missing, max_tolerated);
> + free_extent_map(em);
> + goto out;
> + }
> + next_start = extent_map_end(em);
> + free_extent_map(em);
> +
> + read_lock(&map_tree->map_tree.lock);
> + em = lookup_extent_mapping(&map_tree->map_tree, next_start,
> + (u64)(-1) - next_start);
> + read_unlock(&map_tree->map_tree.lock);
> + }
> +out:
> + return ret;
> +}
> +
> int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info)
> {
> struct btrfs_root *root = fs_info->chunk_root;
> diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
> index 59be81206dd7..db1b5ef479cf 100644
> --- a/fs/btrfs/volumes.h
> +++ b/fs/btrfs/volumes.h
> @@ -538,4 +538,5 @@ struct list_head *btrfs_get_fs_uuids(void);
> void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
> void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
>
> +bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info);
> #endif
>
next prev parent reply other threads:[~2017-03-13 7:24 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-09 1:34 [PATCH v3.1 0/7] Chunk level degradable check Qu Wenruo
2017-03-09 1:34 ` [PATCH v3.1 1/7] btrfs: Introduce a function to check if all chunks a OK for degraded rw mount Qu Wenruo
2017-03-13 7:29 ` Anand Jain [this message]
2017-03-13 7:25 ` Qu Wenruo
2017-05-01 10:21 ` Dmitrii Tcvetkov
2017-05-02 0:20 ` Qu Wenruo
2017-05-02 2:28 ` Anand Jain
2017-03-09 1:34 ` [PATCH v3.1 2/7] btrfs: Do chunk level rw degrade check at mount time Qu Wenruo
2017-03-09 1:34 ` [PATCH v3.1 3/7] btrfs: Do chunk level degradation check for remount Qu Wenruo
2017-03-09 1:34 ` [PATCH v3.1 4/7] btrfs: Introduce extra_rw_degrade_errors parameter for btrfs_check_rw_degradable Qu Wenruo
2017-03-09 1:34 ` [PATCH v3.1 5/7] btrfs: Allow barrier_all_devices to do chunk level device check Qu Wenruo
2017-03-13 8:00 ` Anand Jain
2017-03-09 1:34 ` [PATCH v3.1 6/7] btrfs: Cleanup num_tolerated_disk_barrier_failures Qu Wenruo
2017-03-09 1:34 ` [PATCH v3.1 7/7] btrfs: Enhance missing device kernel message Qu Wenruo
2017-06-26 18:59 ` [PATCH v3.1 0/7] Chunk level degradable check David Sterba
2017-06-27 1:05 ` Qu Wenruo
2017-06-27 1:59 ` Anand Jain
2017-06-27 2:49 ` Qu Wenruo
2017-06-27 11:20 ` Austin S. Hemmelgarn
2017-06-27 12:20 ` David Sterba
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=f01fd9f3-85fe-c390-5358-be8c5d67ebc6@oracle.com \
--to=anand.jain@oracle.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=quwenruo@cn.fujitsu.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).