lkml.org 
[lkml]   [2017]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs
    Date
    In this patch, we add a new sysfs interface, we can use it to gradually achieve
    the reserved_blocks finally, even when reserved_blocks is initially set over
    user_block_count - total_valid_block_count. This is very useful, especially when
    we upgrade kernel with new reserved_blocks value, but old disk image unluckily has
    user_block_count - total_valid_block_count smaller than the desired reserved_blocks.
    With this patch, f2fs can try its best to reserve space and get close to the
    reserved_blocks, and the current value of achieved reserved_blocks can be shown
    in real time.

    To ensure there is enough space for supporting system's activation, we safely
    increase cur_reserved_blocks in dev_valid_block(,node)_count to only take up the
    blocks which are just obsoleted.

    Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
    ---
    Documentation/ABI/testing/sysfs-fs-f2fs | 6 ++++++
    fs/f2fs/f2fs.h | 9 +++++++--
    fs/f2fs/super.c | 3 ++-
    fs/f2fs/sysfs.c | 15 ++++++++++-----
    4 files changed, 25 insertions(+), 8 deletions(-)

    diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
    index 11b7f4e..bdbb9f3 100644
    --- a/Documentation/ABI/testing/sysfs-fs-f2fs
    +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
    @@ -151,3 +151,9 @@ Date: August 2017
    Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
    Description:
    Controls sleep time of GC urgent mode
    +
    +What: /sys/fs/f2fs/<disk>/cur_reserved_blocks
    +Date: August 2017
    +Contact: "Yunlong Song" <yunlong.song@huawei.com>
    +Description:
    + Shows current reserved blocks in system.
    diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
    index 2f20b6b..62d7343 100644
    --- a/fs/f2fs/f2fs.h
    +++ b/fs/f2fs/f2fs.h
    @@ -1041,6 +1041,7 @@ struct f2fs_sb_info {
    block_t discard_blks; /* discard command candidats */
    block_t last_valid_block_count; /* for recovery */
    block_t reserved_blocks; /* configurable reserved blocks */
    + block_t cur_reserved_blocks; /* current reserved blocks */

    u32 s_next_generation; /* for NFS support */

    @@ -1515,7 +1516,7 @@ static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,

    spin_lock(&sbi->stat_lock);
    sbi->total_valid_block_count += (block_t)(*count);
    - avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
    + avail_user_block_count = sbi->user_block_count - sbi->cur_reserved_blocks;
    if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
    diff = sbi->total_valid_block_count - avail_user_block_count;
    *count -= diff;
    @@ -1549,6 +1550,8 @@ static inline void dec_valid_block_count(struct f2fs_sb_info *sbi,
    f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
    f2fs_bug_on(sbi, inode->i_blocks < sectors);
    sbi->total_valid_block_count -= (block_t)count;
    + sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
    + sbi->cur_reserved_blocks + count);
    spin_unlock(&sbi->stat_lock);
    f2fs_i_blocks_write(inode, count, false, true);
    }
    @@ -1695,7 +1698,7 @@ static inline int inc_valid_node_count(struct f2fs_sb_info *sbi,
    spin_lock(&sbi->stat_lock);

    valid_block_count = sbi->total_valid_block_count + 1;
    - if (unlikely(valid_block_count + sbi->reserved_blocks >
    + if (unlikely(valid_block_count + sbi->cur_reserved_blocks >
    sbi->user_block_count)) {
    spin_unlock(&sbi->stat_lock);
    goto enospc;
    @@ -1738,6 +1741,8 @@ static inline void dec_valid_node_count(struct f2fs_sb_info *sbi,

    sbi->total_valid_node_count--;
    sbi->total_valid_block_count--;
    + sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
    + sbi->cur_reserved_blocks + 1);

    spin_unlock(&sbi->stat_lock);

    diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
    index 4c1bdcb..16a805f 100644
    --- a/fs/f2fs/super.c
    +++ b/fs/f2fs/super.c
    @@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
    buf->f_blocks = total_count - start_count;
    buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
    buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
    - sbi->reserved_blocks;
    + sbi->cur_reserved_blocks;

    avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;

    @@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
    le64_to_cpu(sbi->ckpt->valid_block_count);
    sbi->last_valid_block_count = sbi->total_valid_block_count;
    sbi->reserved_blocks = 0;
    + sbi->cur_reserved_blocks = 0;

    for (i = 0; i < NR_INODE_TYPE; i++) {
    INIT_LIST_HEAD(&sbi->inode_list[i]);
    diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
    index a1be5ac..03f9d3d 100644
    --- a/fs/f2fs/sysfs.c
    +++ b/fs/f2fs/sysfs.c
    @@ -76,6 +76,12 @@ static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
    BD_PART_WRITTEN(sbi)));
    }

    +static ssize_t cur_reserved_blocks_show(struct f2fs_attr *a,
    + struct f2fs_sb_info *sbi, char *buf)
    +{
    + return snprintf(buf, PAGE_SIZE, "%u\n", sbi->cur_reserved_blocks);
    +}
    +
    static ssize_t features_show(struct f2fs_attr *a,
    struct f2fs_sb_info *sbi, char *buf)
    {
    @@ -143,12 +149,9 @@ static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
    #endif
    if (a->struct_type == RESERVED_BLOCKS) {
    spin_lock(&sbi->stat_lock);
    - if ((unsigned long)sbi->total_valid_block_count + t >
    - (unsigned long)sbi->user_block_count) {
    - spin_unlock(&sbi->stat_lock);
    - return -EINVAL;
    - }
    *ui = t;
    + if (t < sbi->cur_reserved_blocks)
    + sbi->cur_reserved_blocks = t;
    spin_unlock(&sbi->stat_lock);
    return count;
    }
    @@ -274,6 +277,7 @@ static ssize_t f2fs_feature_show(struct f2fs_attr *a,
    #endif
    F2FS_GENERAL_RO_ATTR(lifetime_write_kbytes);
    F2FS_GENERAL_RO_ATTR(features);
    +F2FS_GENERAL_RO_ATTR(cur_reserved_blocks);

    #ifdef CONFIG_F2FS_FS_ENCRYPTION
    F2FS_FEATURE_RO_ATTR(encryption, FEAT_CRYPTO);
    @@ -317,6 +321,7 @@ static ssize_t f2fs_feature_show(struct f2fs_attr *a,
    ATTR_LIST(lifetime_write_kbytes),
    ATTR_LIST(features),
    ATTR_LIST(reserved_blocks),
    + ATTR_LIST(cur_reserved_blocks),
    NULL,
    };

    --
    1.8.5.2
    \
     
     \ /
      Last update: 2017-08-11 13:45    [W:5.062 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site