lkml.org 
[lkml]   [2008]   [Jul]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 27/52] ext4: mballoc avoid use root reserved blocks for non root allocation
    Date
    From: Mingming Cao <cmm@us.ibm.com>

    mballoc allocation missed check for blocks reserved for root users. Add
    ext4_has_free_blocks() check before allocation. Also modified
    ext4_has_free_blocks() to support multiple block allocation request.

    Signed-off-by: Mingming Cao <cmm@us.ibm.com>
    Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
    ---
    fs/ext4/balloc.c | 51 +++++++++++++++++++++++++++++++++------------------
    fs/ext4/ext4.h | 2 ++
    fs/ext4/mballoc.c | 7 ++++++-
    3 files changed, 41 insertions(+), 19 deletions(-)

    diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
    index 48787e8..25f63d8 100644
    --- a/fs/ext4/balloc.c
    +++ b/fs/ext4/balloc.c
    @@ -1599,23 +1599,35 @@ out:

    /**
    * ext4_has_free_blocks()
    - * @sbi: in-core super block structure.
    + * @sbi: in-core super block structure.
    + * @nblocks: number of neeed blocks
    *
    - * Check if filesystem has at least 1 free block available for allocation.
    + * Check if filesystem has free blocks available for allocation.
    + * Return the number of blocks avaible for allocation for this request
    + * On success, return nblocks
    */
    -static int ext4_has_free_blocks(struct ext4_sb_info *sbi)
    +ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
    + ext4_fsblk_t nblocks)
    {
    - ext4_fsblk_t free_blocks, root_blocks;
    + ext4_fsblk_t free_blocks;
    + ext4_fsblk_t root_blocks = 0;

    free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
    - root_blocks = ext4_r_blocks_count(sbi->s_es);
    - if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
    +
    + if (!capable(CAP_SYS_RESOURCE) &&
    sbi->s_resuid != current->fsuid &&
    - (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
    - return 0;
    - }
    - return 1;
    -}
    + (sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
    + root_blocks = ext4_r_blocks_count(sbi->s_es);
    +#ifdef CONFIG_SMP
    + if (free_blocks - root_blocks < FBC_BATCH)
    + free_blocks =
    + percpu_counter_sum_positive(&sbi->s_freeblocks_counter);
    +#endif
    + if (free_blocks - root_blocks < nblocks)
    + return free_blocks - root_blocks;
    + return nblocks;
    + }
    +

    /**
    * ext4_should_retry_alloc()
    @@ -1631,7 +1643,7 @@ static int ext4_has_free_blocks(struct ext4_sb_info *sbi)
    */
    int ext4_should_retry_alloc(struct super_block *sb, int *retries)
    {
    - if (!ext4_has_free_blocks(EXT4_SB(sb)) || (*retries)++ > 3)
    + if (!ext4_has_free_blocks(EXT4_SB(sb), 1) || (*retries)++ > 3)
    return 0;

    jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
    @@ -1681,13 +1693,21 @@ ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
    ext4_group_t ngroups;
    unsigned long num = *count;

    - *errp = -ENOSPC;
    sb = inode->i_sb;
    if (!sb) {
    + *errp = -ENODEV;
    printk("ext4_new_block: nonexistent device");
    return 0;
    }

    + sbi = EXT4_SB(sb);
    + *count = ext4_has_free_blocks(sbi, *count);
    + if (*count == 0) {
    + *errp = -ENOSPC;
    + return 0; /*return with ENOSPC error */
    + }
    + num = *count;
    +
    /*
    * Check quota for allocation of this block.
    */
    @@ -1711,11 +1731,6 @@ ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
    if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
    my_rsv = &block_i->rsv_window_node;

    - if (!ext4_has_free_blocks(sbi)) {
    - *errp = -ENOSPC;
    - goto out;
    - }
    -
    /*
    * First, test whether the goal block is free.
    */
    diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
    index ed04642..37ce906 100644
    --- a/fs/ext4/ext4.h
    +++ b/fs/ext4/ext4.h
    @@ -979,6 +979,8 @@ extern ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
    unsigned long *count, int *errp);
    extern ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
    ext4_fsblk_t goal, unsigned long *count, int *errp);
    +extern ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
    + ext4_fsblk_t nblocks);
    extern void ext4_free_blocks (handle_t *handle, struct inode *inode,
    ext4_fsblk_t block, unsigned long count, int metadata);
    extern void ext4_free_blocks_sb (handle_t *handle, struct super_block *sb,
    diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
    index 007b97b..9ffad23 100644
    --- a/fs/ext4/mballoc.c
    +++ b/fs/ext4/mballoc.c
    @@ -4039,6 +4039,12 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
    &(ar->len), errp);
    return block;
    }
    + ar->len = ext4_has_free_blocks(sbi, ar->len);
    +
    + if (ar->len == 0) {
    + *errp = -ENOSPC;
    + return 0;
    + }

    while (ar->len && DQUOT_ALLOC_BLOCK(ar->inode, ar->len)) {
    ar->flags |= EXT4_MB_HINT_NOPREALLOC;
    @@ -4067,7 +4073,6 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,

    ac->ac_op = EXT4_MB_HISTORY_PREALLOC;
    if (!ext4_mb_use_preallocated(ac)) {
    -
    ac->ac_op = EXT4_MB_HISTORY_ALLOC;
    ext4_mb_normalize_request(ac, ar);
    repeat:
    --
    1.5.6.rc3.1.g36b7.dirty


    \
     
     \ /
      Last update: 2008-07-05 19:47    [W:3.263 / U:0.372 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site