lkml.org 
[lkml]   [2008]   [Jan]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 2/2][RFC][BUG] msync: updating ctime and mtime at syncing
From
Date

On Fri, 2008-01-11 at 03:44 +0300, Anton Salikhmetov wrote:

> +/*
> + * Update the ctime and mtime stamps after checking if they are to be updated.
> + */
> +void mapped_file_update_time(struct file *file)
> +{
> + if (test_and_clear_bit(AS_MCTIME, &file->f_mapping->flags)) {
> + get_file(file);
> + file_update_time(file);
> + fput(file);
> + }
> +}
> +

I don't think you need the get/put file stuff here, because

> @@ -87,6 +87,8 @@ long do_fsync(struct file *file, int datasync)
> goto out;
> }
>
> + mapped_file_update_time(file);
> +
> ret = filemap_fdatawrite(mapping);
>
> /*

at this call-site we already hold an extra reference on the file, and

> @@ -74,14 +79,17 @@ asmlinkage long sys_msync(unsigned long start, size_t len, int flags)
> break;
> }
> file = vma->vm_file;
> - if ((flags & MS_SYNC) && file && (vma->vm_flags & VM_SHARED)) {
> - get_file(file);
> - up_read(&mm->mmap_sem);
> - error = do_fsync(file, 0);
> - fput(file);
> - if (error)
> - return error;
> - down_read(&mm->mmap_sem);
> + if (file && (vma->vm_flags & VM_SHARED)) {
> + mapped_file_update_time(file);
> + if (flags & MS_SYNC) {
> + get_file(file);
> + up_read(&mm->mmap_sem);
> + error = do_fsync(file, 0);
> + fput(file);
> + if (error)
> + return error;
> + down_read(&mm->mmap_sem);
> + }
> }
>
> start = vma->vm_end;

here we hold the mmap_sem so the vma reference on the file can't go
away.



\
 
 \ /
  Last update: 2008-01-12 10:39    [W:0.172 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site