[Devel] [PATCH RHEL8 COMMIT] ploop: Read metadata page-aligned

[Konstantin Khorenko]

The commit is pushed to "branch-rh8-4.18.0-240.1.1.vz8.5.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh8-4.18.0-240.1.1.vz8.5.51
------>
commit 4cd4788062fe06933a240db244c427dc50e11063
Author: Kirill Tkhai <ktkhai at virtuozzo.com>
Date:   Fri Jul 2 22:51:51 2021 +0300

    ploop: Read metadata page-aligned
    
    File open with O_DIRECT results in direct read,
    even if we do that synchronous from kernel.
    
    iov_iter_get_pages()
    
    Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
    
    ==========================
    ploop: Stop using kvec
    
    We can't read using kvec from file open with O_DIRECT.
    This makes ploop to stop use it.
    
    Kirill Tkhai (8):
          ploop: Read metadata page-aligned
          ploop: RAW image does not have header
          ploop: Introduce ploop_init_be_iter()
          ploop: Introduce rb_root_for_each_md_page()
          ploop: Introduce md helpers
          ploop: Stop using kvec
          ploop: Kill dead check
          ploop: Shorten delta_bat_entries
---
 drivers/md/dm-ploop-bat.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/md/dm-ploop-bat.c b/drivers/md/dm-ploop-bat.c
index f55956aab5a7..90ddba88494f 100644
--- a/drivers/md/dm-ploop-bat.c
+++ b/drivers/md/dm-ploop-bat.c
@@ -369,6 +369,7 @@ int ploop_read_delta_metadata(struct ploop *ploop, struct file *file,
 	int ret;
 
 	size = (PLOOP_MAP_OFFSET + ploop->nr_bat_entries) * sizeof(map_index_t);
+	size = ALIGN(size, PAGE_SIZE); /* file may be open as direct */
 	*d_hdr = vzalloc(size);
 	if (!*d_hdr) {
 		ret = -ENOMEM;