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| author | Pavel Emelyanov <xemul@parallels.com> | 2015-09-05 00:46:34 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-05 01:54:41 +0200 |
| commit | 3f602d2724b1f7d2d27ddcd7963a040a5890fd16 (patch) | |
| tree | bb15462c57939ce4793c586b01e4218d2633a79a | |
| parent | userfaultfd: add new syscall to provide memory externalization (diff) | |
| download | linux-3f602d2724b1f7d2d27ddcd7963a040a5890fd16.tar.xz linux-3f602d2724b1f7d2d27ddcd7963a040a5890fd16.zip | |
userfaultfd: Rename uffd_api.bits into .features
This is (seems to be) the minimal thing that is required to unblock
standard uffd usage from the non-cooperative one. Now more bits can be
added to the features field indicating e.g. UFFD_FEATURE_FORK and others
needed for the latter use-case.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/userfaultfd.c | 4 | ||||
| -rw-r--r-- | include/uapi/linux/userfaultfd.h | 12 |
2 files changed, 11 insertions, 5 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 9bc256d1a143..0756d97b0666 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -884,7 +884,7 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx, goto out; } /* careful not to leak info, we only read the first 8 bytes */ - uffdio_api.bits = UFFD_API_BITS; + uffdio_api.features = UFFD_API_FEATURES; uffdio_api.ioctls = UFFD_API_IOCTLS; ret = -EFAULT; if (copy_to_user(buf, &uffdio_api, sizeof(uffdio_api))) @@ -941,7 +941,7 @@ 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_BITS, + pending, total, UFFD_API, UFFD_API_FEATURES, UFFD_API_IOCTLS|UFFD_API_RANGE_IOCTLS); } #endif diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 09c2e2a8c9d6..330206016249 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -12,8 +12,8 @@ #include <linux/types.h> #define UFFD_API ((__u64)0xAA) -/* FIXME: add "|UFFD_BIT_WP" to UFFD_API_BITS after implementing it */ -#define UFFD_API_BITS (UFFD_BIT_WRITE) +/* FIXME: add "|UFFD_FEATURE_WP" to UFFD_API_FEATURES after implementing it */ +#define UFFD_API_FEATURES (UFFD_FEATURE_WRITE_BIT) #define UFFD_API_IOCTLS \ ((__u64)1 << _UFFDIO_REGISTER | \ (__u64)1 << _UFFDIO_UNREGISTER | \ @@ -53,12 +53,18 @@ #define UFFD_BIT_WP (1<<1) /* handle_userfault() reason VM_UFFD_WP */ #define UFFD_BITS 2 /* two above bits used for UFFD_BIT_* mask */ +/* + * Features reported in uffdio_api.features field + */ +#define UFFD_FEATURE_WRITE_BIT (1<<0) /* Corresponds to UFFD_BIT_WRITE */ +#define UFFD_FEATURE_WP_BIT (1<<1) /* Corresponds to UFFD_BIT_WP */ + struct uffdio_api { /* userland asks for an API number */ __u64 api; /* kernel answers below with the available features for the API */ - __u64 bits; + __u64 features; __u64 ioctls; }; |