Implement stacked fadvise to fix syscalls readahead(2) and fadvise64(2) on an overlayfs file. Suggested-by: Miklos Szeredi <mszeredi@xxxxxxxxxx> Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- fs/overlayfs/file.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index a4acd84591d4..42d2d034d85c 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -331,6 +331,23 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len return ret; } +int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice) +{ + struct fd real; + int ret; + + ret = ovl_real_fdget(file, &real); + if (ret) + return ret; + + /* XXX: do we need mounter credentials? */ + ret = vfs_fadvise(real.file, offset, len, advice); + + fdput(real); + + return ret; +} + static long ovl_real_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -499,6 +516,7 @@ const struct file_operations ovl_file_operations = { .fsync = ovl_fsync, .mmap = ovl_mmap, .fallocate = ovl_fallocate, + .fadvise = ovl_fadvise, .unlocked_ioctl = ovl_ioctl, .compat_ioctl = ovl_compat_ioctl, -- 2.7.4