lkml.org 
[lkml]   [2018]   [Jul]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[RFC][PATCH 24/27] new helper: alloc_file_clone()
    Date
    From: Al Viro <viro@zeniv.linux.org.uk>

    alloc_file_clone(old_file, mode, ops): create a new struct file with
    ->f_path equal to that of old_file. pipe converted.

    Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
    ---
    fs/file_table.c | 11 +++++++++++
    fs/pipe.c | 5 +----
    include/linux/file.h | 2 ++
    3 files changed, 14 insertions(+), 4 deletions(-)

    diff --git a/fs/file_table.c b/fs/file_table.c
    index d78bc97f926f..fb7c3b007630 100644
    --- a/fs/file_table.c
    +++ b/fs/file_table.c
    @@ -209,6 +209,17 @@ struct file *alloc_file_pseudo(struct inode *inode, struct vfsmount *mnt,
    }
    EXPORT_SYMBOL(alloc_file_pseudo);

    +struct file *alloc_file_clone(struct file *base, fmode_t mode,
    + const struct file_operations *fops)
    +{
    + struct file *f = alloc_file(&base->f_path, mode | FMODE_OPENED, fops);
    + if (!IS_ERR(f)) {
    + path_get(&f->f_path);
    + f->f_mapping = base->f_mapping;
    + }
    + return f;
    +}
    +
    /* the real guts of fput() - releasing the last reference to file
    */
    static void __fput(struct file *file)
    diff --git a/fs/pipe.c b/fs/pipe.c
    index 312af057f03a..94323a1d7c92 100644
    --- a/fs/pipe.c
    +++ b/fs/pipe.c
    @@ -760,15 +760,12 @@ int create_pipe_files(struct file **res, int flags)
    f->f_flags = O_WRONLY | (flags & (O_NONBLOCK | O_DIRECT));
    f->private_data = inode->i_pipe;

    - res[0] = alloc_file(&f->f_path, FMODE_READ | FMODE_OPENED,
    - &pipefifo_fops);
    + res[0] = alloc_file_clone(f, FMODE_READ, &pipefifo_fops);
    if (IS_ERR(res[0])) {
    put_pipe_info(inode, inode->i_pipe);
    fput(f);
    return PTR_ERR(res[0]);
    }
    -
    - path_get(&f->f_path);
    res[0]->private_data = inode->i_pipe;
    res[0]->f_flags = O_RDONLY | (flags & O_NONBLOCK);
    res[1] = f;
    diff --git a/include/linux/file.h b/include/linux/file.h
    index 37a4d2c166de..c2e38ec2ee7f 100644
    --- a/include/linux/file.h
    +++ b/include/linux/file.h
    @@ -23,6 +23,8 @@ extern struct file *alloc_file(const struct path *, fmode_t mode,
    const struct file_operations *fop);
    extern struct file *alloc_file_pseudo(struct inode *, struct vfsmount *,
    const char *, fmode_t, const struct file_operations *);
    +extern struct file *alloc_file_clone(struct file *, fmode_t,
    + const struct file_operations *);

    static inline void fput_light(struct file *file, int fput_needed)
    {
    --
    2.11.0
    \
     
     \ /
      Last update: 2018-07-09 06:56    [W:2.829 / U:0.188 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site