On Wed, Nov 14, 2018 at 09:17:11PM +0800, Anand Jain wrote:
> Balance arg info is an important information to be reviewed for the
> system audit. So this patch adds them to the kernel log.
>
> Example:
> ->btrfs bal start -f -mprofiles=raid1,convert=single,soft -dlimit=10..20,usage=50 /btrfs
>
> kernel: BTRFS info (device sdb): balance: start -f -dusage=50,limit=10..20 -msoft,profiles=raid1,convert=single -ssoft,profiles=raid1,convert=single
>
> Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx>
> ---
> v4.1->v5: Per David review comment the code..
> bp += snprintf(bp, buf - bp + size_buf, "soft,");
> is not safe if 'buf - bp + size_buf' becomes accidentally
> negative, so fix this by using following snprintf.
>
> #define CHECK_UPDATE_BP_1(a) \
> do { \
> ret = snprintf(bp, size_bp, a); \
> if (ret < 0 || ret >= size_bp) \
> goto out; \
> size_bp -= ret; \
> bp += ret; \
> } while (0)
>
> And initialize the tmp_buf to null.
>
> v4->v4.1: Rename last missed sz to size_buf.
>
> v3->v4: Change log updated with new example.
> Log format is changed to almost match with the cli.
> snprintf drop %s for inline string.
> Print range as =%u..%u instead of min=%umax=%u.
> soft is under the args now.
> force is printed as -f.
>
> v2->v3: Change log updated.
> Make use of describe_block_group() added in 1/4
> Drop using strcat instead use snprintf.
> Logs string format updated as shown in the example above.
>
> v1->v2: Change log update.
> Move adding the logs for balance complete and end to a new patch
>
> fs/btrfs/volumes.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 169 insertions(+), 3 deletions(-)
>
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 12b3d0625c6a..8397f72bdac7 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -3754,6 +3754,173 @@ static inline int validate_convert_profile(struct btrfs_balance_args *bctl_arg,
> (bctl_arg->target & ~allowed)));
> }
>
> +static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
> + u32 size_buf)
> +{
> + int ret;
> + u32 size_bp = size_buf;
> + char *bp = buf;
> + u64 flags = bargs->flags;
> + char tmp_buf[128] = {'\0'};
> +
> + if (!flags)
> + return;
> +
> +#define CHECK_UPDATE_BP_1(a) \
CHECK_UPDATE_BP_NOARG and the others CHECK_UPDATE_BP_1ARG, though I'm
thinking about picking another name for the macro like CHECK_APPEND_2ARG
etc.
> + do { \
> + ret = snprintf(bp, size_bp, a); \
> + if (ret < 0 || ret >= size_bp) \
> + goto out; \
out_overflow and align \ to the right, please.
> + size_bp -= ret; \
> + bp += ret; \
> + } while (0)
> +
> +#define CHECK_UPDATE_BP_2(a, v1) \
> + do { \
> + ret = snprintf(bp, size_bp, a, v1); \
> + if (ret < 0 || ret >= size_bp) \
> + goto out; \
> + size_bp -= ret; \
> + bp += ret; \
> + } while (0)
> +
> +#define CHECK_UPDATE_BP_3(a, v1, v2) \
> + do { \
> + ret = snprintf(bp, size_bp, a, v1, v2); \
> + if (ret < 0 || ret >= size_bp) \
> + goto out; \
> + size_bp -= ret; \
> + bp += ret; \
> + } while (0)
> +
> + if (flags & BTRFS_BALANCE_ARGS_SOFT) {
> + CHECK_UPDATE_BP_1("soft,");
> + }
no { } around single statement
> +
> + if (flags & BTRFS_BALANCE_ARGS_PROFILES) {
> + btrfs_describe_block_groups(bargs->profiles, tmp_buf,
> + sizeof(tmp_buf));
> + CHECK_UPDATE_BP_2("profiles=%s,", tmp_buf);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_USAGE) {
> + CHECK_UPDATE_BP_2("usage=%llu,", bargs->usage);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) {
> + CHECK_UPDATE_BP_3("usage=%u..%u,",
> + bargs->usage_min, bargs->usage_max);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_DEVID) {
> + CHECK_UPDATE_BP_2("devid=%llu,", bargs->devid);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_DRANGE) {
> + CHECK_UPDATE_BP_3("drange=%llu..%llu,",
> + bargs->pstart, bargs->pend);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_VRANGE) {
> + CHECK_UPDATE_BP_3("vrange%llu..%llu,",
> + bargs->vstart, bargs->vend);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_LIMIT) {
> + CHECK_UPDATE_BP_2("limit=%llu,", bargs->limit);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE) {
> + CHECK_UPDATE_BP_3("limit=%u..%u,",
> + bargs->limit_min, bargs->limit_max);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) {
> + CHECK_UPDATE_BP_3("stripes=%u..%u,",
> + bargs->stripes_min, bargs->stripes_max);
> + }
> +
> + if (flags & BTRFS_BALANCE_ARGS_CONVERT) {
> + int index = btrfs_bg_flags_to_raid_index(bargs->target);
> +
> + CHECK_UPDATE_BP_2("convert=%s,", get_raid_name(index));
> + }
> +
> +out:
> +#undef CHECK_UPDATE_BP_3
> +#undef CHECK_UPDATE_BP_2
> +#undef CHECK_UPDATE_BP_1
> +
> + if (size_bp < size_buf)
> + buf[size_buf - size_bp - 1] = '\0'; /* remove last , */
> + else
> + buf[0] = '\0';
> +}
> +
> +static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info)
> +{
> + u32 size_buf = 1024;
> + char tmp_buf[192] = {'\0'};
> + char *buf;
> + char *bp;
> + u32 size_bp = size_buf;
> + int ret;
> + struct btrfs_balance_control *bctl = fs_info->balance_ctl;
> +
> + buf = kzalloc(size_buf, GFP_KERNEL);
> + if (!buf)
> + return;
> +
> + bp = buf;
> +#define CHECK_UPDATE_BP_1(a) \
> + do { \
> + ret = snprintf(bp, size_bp, a); \
> + if (ret < 0 || ret >= size_bp) \
> + return; \
> + size_bp -= ret; \
> + bp += ret; \
> + } while (0)
> +
> +#define CHECK_UPDATE_BP_2(a, v1) \
> + do { \
> + ret = snprintf(bp, size_bp, a, v1); \
> + if (ret < 0 || ret >= size_bp) \
> + return; \
> + size_bp -= ret; \
> + bp += ret; \
> + } while (0)
> +
> + if (bctl->flags & BTRFS_BALANCE_FORCE) {
> + CHECK_UPDATE_BP_1("-f ");
> + }
> +
> + if (bctl->flags & BTRFS_BALANCE_DATA) {
> + describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf));
> + CHECK_UPDATE_BP_2("-d%s ", tmp_buf);
> + }
> +
> + if (bctl->flags & BTRFS_BALANCE_METADATA) {
> + describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf));
> + CHECK_UPDATE_BP_2("-m%s ", tmp_buf);
> + }
> +
> + if (bctl->flags & BTRFS_BALANCE_SYSTEM) {
> + describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf));
> + CHECK_UPDATE_BP_2("-s%s ", tmp_buf);
> + }
> +
> +#undef CHECK_UPDATE_BP_2
> +#undef CHECK_UPDATE_BP_1
> +
> + if (size_bp < size_buf)
> + buf[size_buf - size_bp - 1] = '\0'; /* remove last " "*/
> + btrfs_info(fs_info, "%s %s",
> + bctl->flags & BTRFS_BALANCE_RESUME ?
> + "balance: resume":"balance: start", buf);
> +
> + kfree(buf);
> +}
> +
> /*
> * Should be called with balance mutexe held
> */
> @@ -3893,6 +4060,7 @@ int btrfs_balance(struct btrfs_fs_info *fs_info,
>
> ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
> set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
> + describe_balance_start_or_resume(fs_info);
> mutex_unlock(&fs_info->balance_mutex);
>
> ret = __btrfs_balance(fs_info);
> @@ -3930,10 +4098,8 @@ static int balance_kthread(void *data)
> int ret = 0;
>
> mutex_lock(&fs_info->balance_mutex);
> - if (fs_info->balance_ctl) {
> - btrfs_info(fs_info, "balance: resuming");
> + if (fs_info->balance_ctl)
> ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL);
> - }
> mutex_unlock(&fs_info->balance_mutex);
>
> return ret;
> --
> 1.8.3.1
