From b833a3660394876541d2513ce2736debc7c6797a Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 28 Aug 2018 10:58:41 +0300 Subject: ovl: add ovl_fadvise() Implement stacked fadvise to fix syscalls readahead(2) and fadvise64(2) on an overlayfs file. Suggested-by: Miklos Szeredi Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/file.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'fs') diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index a4acd84591d4..aeaefd2a551b 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -331,6 +331,25 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len return ret; } +static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice) +{ + struct fd real; + const struct cred *old_cred; + int ret; + + ret = ovl_real_fdget(file, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(file)->i_sb); + ret = vfs_fadvise(real.file, offset, len, advice); + revert_creds(old_cred); + + fdput(real); + + return ret; +} + static long ovl_real_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -499,6 +518,7 @@ 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, -- cgit v1.2.3-58-ga151