lkml.org 
[lkml]   [2019]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.0 108/238] ext4: cleanup pagecache before swap i_data
    Date
    5.0-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: yangerkun <yangerkun@huawei.com>

    commit a46c68a318b08f819047843abf349aeee5d10ac2 upstream.

    While do swap, we should make sure there has no new dirty page since we
    should swap i_data between two inode:
    1.We should lock i_mmap_sem with write to avoid new pagecache from mmap
    read/write;
    2.Change filemap_flush to filemap_write_and_wait and move them to the
    space protected by inode lock to avoid new pagecache from buffer read/write.

    Signed-off-by: yangerkun <yangerkun@huawei.com>
    Signed-off-by: Theodore Ts'o <tytso@mit.edu>
    Cc: stable@kernel.org
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    fs/ext4/ioctl.c | 16 ++++++++++++----
    1 file changed, 12 insertions(+), 4 deletions(-)

    --- a/fs/ext4/ioctl.c
    +++ b/fs/ext4/ioctl.c
    @@ -121,9 +121,6 @@ static long swap_inode_boot_loader(struc
    return PTR_ERR(inode_bl);
    ei_bl = EXT4_I(inode_bl);

    - filemap_flush(inode->i_mapping);
    - filemap_flush(inode_bl->i_mapping);
    -
    /* Protect orig inodes against a truncate and make sure,
    * that only 1 swap_inode_boot_loader is running. */
    lock_two_nondirectories(inode, inode_bl);
    @@ -141,6 +138,15 @@ static long swap_inode_boot_loader(struc
    goto journal_err_out;
    }

    + down_write(&EXT4_I(inode)->i_mmap_sem);
    + err = filemap_write_and_wait(inode->i_mapping);
    + if (err)
    + goto err_out;
    +
    + err = filemap_write_and_wait(inode_bl->i_mapping);
    + if (err)
    + goto err_out;
    +
    /* Wait for all existing dio workers */
    inode_dio_wait(inode);
    inode_dio_wait(inode_bl);
    @@ -151,7 +157,7 @@ static long swap_inode_boot_loader(struc
    handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
    if (IS_ERR(handle)) {
    err = -EINVAL;
    - goto journal_err_out;
    + goto err_out;
    }

    /* Protect extent tree against block allocations via delalloc */
    @@ -208,6 +214,8 @@ static long swap_inode_boot_loader(struc
    ext4_journal_stop(handle);
    ext4_double_up_write_data_sem(inode, inode_bl);

    +err_out:
    + up_write(&EXT4_I(inode)->i_mmap_sem);
    journal_err_out:
    unlock_two_nondirectories(inode, inode_bl);
    iput(inode_bl);

    \
     
     \ /
      Last update: 2019-03-22 13:32    [W:5.269 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site