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| author |   Mike Rapoport <rppt@linux.vnet.ibm.com> | 2017-04-07 16:04:42 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2017-04-08 00:47:48 -0700 |
| commit | 045098e944959d4cbd56bbf33e2f26045863b7ca (patch) | |
| tree | 8495ab4992f0a50304649c67016b2b965b515db6 /fs | |
| parent | mm: fix page_vma_mapped_walk() for ksm pages (diff) | |
| download | linux-dev-045098e944959d4cbd56bbf33e2f26045863b7ca.tar.xz linux-dev-045098e944959d4cbd56bbf33e2f26045863b7ca.zip | |
userfaultfd: report actual registered features in fdinfo
fdinfo for userfault file descriptor reports UFFD_API_FEATURES. Up
until recently, the UFFD_API_FEATURES was defined as 0, therefore
corresponding field in fdinfo always contained zero. Now, with
introduction of several additional features, UFFD_API_FEATURES is not
longer 0 and it seems better to report actual features requested for the
userfaultfd object described by the fdinfo.
First, the applications that were using userfault will still see zero at
the features field in fdinfo. Next, reporting actual features rather
than available features, gives clear indication of what userfault
features are used by an application.
Link: http://lkml.kernel.org/r/1491140181-22121-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/userfaultfd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 1d227b0fcf49..f7555fc25877 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1756,7 +1756,7 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f) * protocols: aa:... bb:... */ seq_printf(m, "pending:\t%lu\ntotal:\t%lu\nAPI:\t%Lx:%x:%Lx\n", - pending, total, UFFD_API, UFFD_API_FEATURES, + pending, total, UFFD_API, ctx->features, UFFD_API_IOCTLS|UFFD_API_RANGE_IOCTLS); } #endif |