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Diffstat (limited to 'include/uapi/linux/userfaultfd.h')
-rw-r--r--include/uapi/linux/userfaultfd.h90
1 files changed, 87 insertions, 3 deletions
diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h
index 05b31d60acf6..2841e4ea8f2c 100644
--- a/include/uapi/linux/userfaultfd.h
+++ b/include/uapi/linux/userfaultfd.h
@@ -12,6 +12,10 @@
#include <linux/types.h>
+/* ioctls for /dev/userfaultfd */
+#define USERFAULTFD_IOC 0xAA
+#define USERFAULTFD_IOC_NEW _IO(USERFAULTFD_IOC, 0x00)
+
/*
* If the UFFDIO_API is upgraded someday, the UFFDIO_UNREGISTER and
* UFFDIO_WAKE ioctls should be defined as _IOW and not as _IOR. In
@@ -32,7 +36,13 @@
UFFD_FEATURE_SIGBUS | \
UFFD_FEATURE_THREAD_ID | \
UFFD_FEATURE_MINOR_HUGETLBFS | \
- UFFD_FEATURE_MINOR_SHMEM)
+ UFFD_FEATURE_MINOR_SHMEM | \
+ UFFD_FEATURE_EXACT_ADDRESS | \
+ UFFD_FEATURE_WP_HUGETLBFS_SHMEM | \
+ UFFD_FEATURE_WP_UNPOPULATED | \
+ UFFD_FEATURE_POISON | \
+ UFFD_FEATURE_WP_ASYNC | \
+ UFFD_FEATURE_MOVE)
#define UFFD_API_IOCTLS \
((__u64)1 << _UFFDIO_REGISTER | \
(__u64)1 << _UFFDIO_UNREGISTER | \
@@ -41,12 +51,16 @@
((__u64)1 << _UFFDIO_WAKE | \
(__u64)1 << _UFFDIO_COPY | \
(__u64)1 << _UFFDIO_ZEROPAGE | \
+ (__u64)1 << _UFFDIO_MOVE | \
(__u64)1 << _UFFDIO_WRITEPROTECT | \
- (__u64)1 << _UFFDIO_CONTINUE)
+ (__u64)1 << _UFFDIO_CONTINUE | \
+ (__u64)1 << _UFFDIO_POISON)
#define UFFD_API_RANGE_IOCTLS_BASIC \
((__u64)1 << _UFFDIO_WAKE | \
(__u64)1 << _UFFDIO_COPY | \
- (__u64)1 << _UFFDIO_CONTINUE)
+ (__u64)1 << _UFFDIO_WRITEPROTECT | \
+ (__u64)1 << _UFFDIO_CONTINUE | \
+ (__u64)1 << _UFFDIO_POISON)
/*
* Valid ioctl command number range with this API is from 0x00 to
@@ -61,8 +75,10 @@
#define _UFFDIO_WAKE (0x02)
#define _UFFDIO_COPY (0x03)
#define _UFFDIO_ZEROPAGE (0x04)
+#define _UFFDIO_MOVE (0x05)
#define _UFFDIO_WRITEPROTECT (0x06)
#define _UFFDIO_CONTINUE (0x07)
+#define _UFFDIO_POISON (0x08)
#define _UFFDIO_API (0x3F)
/* userfaultfd ioctl ids */
@@ -79,10 +95,14 @@
struct uffdio_copy)
#define UFFDIO_ZEROPAGE _IOWR(UFFDIO, _UFFDIO_ZEROPAGE, \
struct uffdio_zeropage)
+#define UFFDIO_MOVE _IOWR(UFFDIO, _UFFDIO_MOVE, \
+ struct uffdio_move)
#define UFFDIO_WRITEPROTECT _IOWR(UFFDIO, _UFFDIO_WRITEPROTECT, \
struct uffdio_writeprotect)
#define UFFDIO_CONTINUE _IOWR(UFFDIO, _UFFDIO_CONTINUE, \
struct uffdio_continue)
+#define UFFDIO_POISON _IOWR(UFFDIO, _UFFDIO_POISON, \
+ struct uffdio_poison)
/* read() structure */
struct uffd_msg {
@@ -189,6 +209,27 @@ struct uffdio_api {
*
* UFFD_FEATURE_MINOR_SHMEM indicates the same support as
* UFFD_FEATURE_MINOR_HUGETLBFS, but for shmem-backed pages instead.
+ *
+ * UFFD_FEATURE_EXACT_ADDRESS indicates that the exact address of page
+ * faults would be provided and the offset within the page would not be
+ * masked.
+ *
+ * UFFD_FEATURE_WP_HUGETLBFS_SHMEM indicates that userfaultfd
+ * write-protection mode is supported on both shmem and hugetlbfs.
+ *
+ * UFFD_FEATURE_WP_UNPOPULATED indicates that userfaultfd
+ * write-protection mode will always apply to unpopulated pages
+ * (i.e. empty ptes). This will be the default behavior for shmem
+ * & hugetlbfs, so this flag only affects anonymous memory behavior
+ * when userfault write-protection mode is registered.
+ *
+ * UFFD_FEATURE_WP_ASYNC indicates that userfaultfd write-protection
+ * asynchronous mode is supported in which the write fault is
+ * automatically resolved and write-protection is un-set.
+ * It implies UFFD_FEATURE_WP_UNPOPULATED.
+ *
+ * UFFD_FEATURE_MOVE indicates that the kernel supports moving an
+ * existing page contents from userspace.
*/
#define UFFD_FEATURE_PAGEFAULT_FLAG_WP (1<<0)
#define UFFD_FEATURE_EVENT_FORK (1<<1)
@@ -201,6 +242,12 @@ struct uffdio_api {
#define UFFD_FEATURE_THREAD_ID (1<<8)
#define UFFD_FEATURE_MINOR_HUGETLBFS (1<<9)
#define UFFD_FEATURE_MINOR_SHMEM (1<<10)
+#define UFFD_FEATURE_EXACT_ADDRESS (1<<11)
+#define UFFD_FEATURE_WP_HUGETLBFS_SHMEM (1<<12)
+#define UFFD_FEATURE_WP_UNPOPULATED (1<<13)
+#define UFFD_FEATURE_POISON (1<<14)
+#define UFFD_FEATURE_WP_ASYNC (1<<15)
+#define UFFD_FEATURE_MOVE (1<<16)
__u64 features;
__u64 ioctls;
@@ -281,6 +328,13 @@ struct uffdio_writeprotect {
struct uffdio_continue {
struct uffdio_range range;
#define UFFDIO_CONTINUE_MODE_DONTWAKE ((__u64)1<<0)
+ /*
+ * UFFDIO_CONTINUE_MODE_WP will map the page write protected on
+ * the fly. UFFDIO_CONTINUE_MODE_WP is available only if the
+ * write protected ioctl is implemented for the range
+ * according to the uffdio_register.ioctls.
+ */
+#define UFFDIO_CONTINUE_MODE_WP ((__u64)1<<1)
__u64 mode;
/*
@@ -290,6 +344,36 @@ struct uffdio_continue {
__s64 mapped;
};
+struct uffdio_poison {
+ struct uffdio_range range;
+#define UFFDIO_POISON_MODE_DONTWAKE ((__u64)1<<0)
+ __u64 mode;
+
+ /*
+ * Fields below here are written by the ioctl and must be at the end:
+ * the copy_from_user will not read past here.
+ */
+ __s64 updated;
+};
+
+struct uffdio_move {
+ __u64 dst;
+ __u64 src;
+ __u64 len;
+ /*
+ * Especially if used to atomically remove memory from the
+ * address space the wake on the dst range is not needed.
+ */
+#define UFFDIO_MOVE_MODE_DONTWAKE ((__u64)1<<0)
+#define UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES ((__u64)1<<1)
+ __u64 mode;
+ /*
+ * "move" is written by the ioctl and must be at the end: the
+ * copy_from_user will not read the last 8 bytes.
+ */
+ __s64 move;
+};
+
/*
* Flags for the userfaultfd(2) system call itself.
*/