From f89e09cf45533eb25ca8e7fbedec697ecb37eb94 Mon Sep 17 00:00:00 2001
From: Anand Jain <anand.jain@oracle.com>
Date: Tue, 20 Nov 2018 16:12:55 +0800
Subject: [PATCH] btrfs: add helper to describe block group flags
Factor out helper that describes block group flags from
describe_relocation. The result will not be longer than the given size.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/relocation.c | 30 +++---------------------
fs/btrfs/volumes.c | 54 +++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/volumes.h | 1 +
3 files changed, 58 insertions(+), 27 deletions(-)
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 5471eea1c0fd..35bfe014712a 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4185,37 +4185,13 @@ static struct reloc_control *alloc_reloc_control(void)
static void describe_relocation(struct btrfs_fs_info *fs_info,
struct btrfs_block_group_cache *block_group)
{
- char buf[128]; /* prefixed by a '|' that'll be dropped */
- u64 flags = block_group->flags;
+ char buf[128] = {'\0'};
- /* Shouldn't happen */
- if (!flags) {
- strcpy(buf, "|NONE");
- } else {
- char *bp = buf;
-
-#define DESCRIBE_FLAG(f, d) \
- if (flags & BTRFS_BLOCK_GROUP_##f) { \
- bp += snprintf(bp, buf - bp + sizeof(buf), "|%s", d); \
- flags &= ~BTRFS_BLOCK_GROUP_##f; \
- }
- DESCRIBE_FLAG(DATA, "data");
- DESCRIBE_FLAG(SYSTEM, "system");
- DESCRIBE_FLAG(METADATA, "metadata");
- DESCRIBE_FLAG(RAID0, "raid0");
- DESCRIBE_FLAG(RAID1, "raid1");
- DESCRIBE_FLAG(DUP, "dup");
- DESCRIBE_FLAG(RAID10, "raid10");
- DESCRIBE_FLAG(RAID5, "raid5");
- DESCRIBE_FLAG(RAID6, "raid6");
- if (flags)
- snprintf(bp, buf - bp + sizeof(buf), "|0x%llx", flags);
-#undef DESCRIBE_FLAG
- }
+ btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf));
btrfs_info(fs_info,
"relocating block group %llu flags %s",
- block_group->key.objectid, buf + 1);
+ block_group->key.objectid, buf);
}
/*
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 2ebc827bed88..bb38b86b8374 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -130,6 +130,60 @@ const char *get_raid_name(enum btrfs_raid_types type)
return btrfs_raid_array[type].raid_name;
}
+/*
+ * Fill @buf with textual description of @bg_flags, no more than @size_buf
+ * bytes including terminating null byte.
+ */
+void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
+{
+ int i;
+ int ret;
+ char *bp = buf;
+ u64 flags = bg_flags;
+ u32 size_bp = size_buf;
+
+ if (!flags) {
+ strcpy(bp, "NONE");
+ return;
+ }
+
+#define DESCRIBE_FLAG(flag, desc) \
+ do { \
+ if (flags & (flag)) { \
+ ret = snprintf(bp, size_bp, "%s|", (desc)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ flags &= ~(flag); \
+ } \
+ } while (0)
+
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
+
+ DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
+ for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
+ DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
+ btrfs_raid_array[i].raid_name);
+#undef DESCRIBE_FLAG
+
+ if (flags) {
+ ret = snprintf(bp, size_bp, "0x%llx|", flags);
+ size_bp -= ret;
+ }
+
+ if (size_bp < size_buf)
+ buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
+
+ /*
+ * The text is trimmed, it's up to the caller to provide sufficiently
+ * large buffer
+ */
+out_overflow:;
+}
+
static int init_first_rw_device(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info);
static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 1d936ce282c3..8b092bb1e2ee 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -438,6 +438,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
int btrfs_balance(struct btrfs_fs_info *fs_info,
struct btrfs_balance_control *bctl,
struct btrfs_ioctl_balance_args *bargs);
+void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);