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.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to