Patch series "mm/vma: convert vm_flags_t to vma_flags_t in vma code", v4.
This series converts a lot of the existing use of the legacy vm_flags_t
data type to the new vma_flags_t type which replaces it.
In order to do so it adds a number of additional helpers:
* vma_flags_empty() - Determines whether a vma_flags_t value has no bits
set.
* vma_flags_and() - Performs a bitwise AND between two vma_flags_t values.
* vma_flags_diff_pair() - Determines which flags are not shared between a
pair of VMA flags (typically non-constant values)
* append_vma_flags() - Similar to mk_vma_flags(), but allows a vma_flags_t
value to be specified (typically a constant value) which will be copied
and appended to to create a new vma_flags_t value, with additional flags
specified to append to it.
* vma_flags_same() - Determines if a vma_flags_t value is exactly equal to
a set of VMA flags.
* vma_flags_same_mask() - Determines if a vma_flags_t value is eactly equal
to another vma_flags_t value (typically constant).
* vma_flags_same_pair() - Determines if a pair of vma_flags_t values are
exactly equal to one another (typically both non-constant).
* vma_flags_to_legacy() - Converts a vma_flags_t value to a vm_flags_t
value, used to enable more iterative introduction of the use of
vma_flags_t.
* legacy_to_vma_flags() - Converts a vm_flags_t value to a vma_flags-t
value, for the same purpose.
* vma_flags_test_single_mask() - Tests whether a vma_flags_t value contain
the single flag specified in an input vma_flags_t flag mask, or if that
flag mask is empty, is defined to return false. Useful for
config-predicated VMA flag mask defines.
* vma_test() - Tests whether a VMA's flags contain a specific singular VMA
flag.
* vma_test_any() - Tests whether a VMA's flags contain any of a set of VMA
flags.
* vma_test_any_mask() - Tests whether a VMA's flags contain any of the
flags specified in another, typically constant, vma_flags_t value.
* vma_test_single_mask() - Tests whether a VMA's flags contain the single
flag specified in an input vma_flags_t flag mask, or if that flag mask is
empty, is defined to return false. Useful for config-predicated VMA flag
mask defines.
* vma_clear_flags() - Clears a specific set of VMA flags from a vma_flags_t
value.
* vma_clear_flags_mask() - Clears those flag set in a vma_flags_t value
(typically constant) from a (typically not constant) vma_flags_t value.
The series mostly focuses on the the VMA specific code, especially that
contained in mm/vma.c and mm/vma.h.
It updates both brk() and mmap() logic to utils vma_flags_t values as much
as is practiaclly possible at this point, changing surrounding logic to be
able to do so.
It also updates the vma_modify_xxx() functions where they interact with VMA
flags directly to use vm_flags_t values where possible.
There is extensive testing added in the VMA userland tests to assert that
all of these new VMA flag functions work correctly.
This patch (of 25):
Firstly, add the ability to determine if VMA flags are empty, that is no
flags are set in a vma_flags_t value.
Next, add the ability to obtain the equivalent of the bitwise and of two
vma_flags_t values, via vma_flags_and_mask().
Next, add the ability to obtain the difference between two sets of VMA
flags, that is the equivalent to the exclusive bitwise OR of the two sets
of flags, via vma_flags_diff_pair().
vma_flags_xxx_mask() typically operates on a pointer to a vma_flags_t
value, which is assumed to be an lvalue of some kind (such as a field in a
struct or a stack variable) and an rvalue of some kind (typically a
constant set of VMA flags obtained e.g. via mk_vma_flags() or
equivalent).
However vma_flags_diff_pair() is intended to operate on two lvalues, so
use the _pair() suffix to make this clear.
Finally, update VMA userland tests to add these helpers.
We also port bitmap_xor() and __bitmap_xor() to the tools/ headers and
source to allow the tests to work with vma_flags_diff_pair().
Link: https://lkml.kernel.org/r/cover.1774034900.git.ljs@kernel.org
Link: https://lkml.kernel.org/r/53ab55b7da91425775e42c03177498ad6de88ef4.1774034900.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Kees Cook <kees@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Ondrej Mosnacek <omosnace@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
return flags;
}
+/*
+ * Helper macro which bitwise-or combines the specified input flags into a
+ * vma_flags_t bitmap value. E.g.:
+ *
+ * vma_flags_t flags = mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT,
+ * VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT);
+ *
+ * The compiler cleverly optimises away all of the work and this ends up being
+ * equivalent to aggregating the values manually.
+ */
+#define mk_vma_flags(...) __mk_vma_flags(COUNT_ARGS(__VA_ARGS__), \
+ (const vma_flag_t []){__VA_ARGS__})
+
/*
* Test whether a specific VMA flag is set, e.g.:
*
}
/*
- * Helper macro which bitwise-or combines the specified input flags into a
- * vma_flags_t bitmap value. E.g.:
- *
- * vma_flags_t flags = mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT,
- * VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT);
+ * Obtain a set of VMA flags which contain the overlapping flags contained
+ * within flags and to_and.
+ */
+static __always_inline vma_flags_t vma_flags_and_mask(const vma_flags_t *flags,
+ vma_flags_t to_and)
+{
+ vma_flags_t dst;
+ unsigned long *bitmap_dst = dst.__vma_flags;
+ const unsigned long *bitmap = flags->__vma_flags;
+ const unsigned long *bitmap_to_and = to_and.__vma_flags;
+
+ bitmap_and(bitmap_dst, bitmap, bitmap_to_and, NUM_VMA_FLAG_BITS);
+ return dst;
+}
+
+/*
+ * Obtain a set of VMA flags which contains the specified overlapping flags,
+ * e.g.:
*
- * The compiler cleverly optimises away all of the work and this ends up being
- * equivalent to aggregating the values manually.
+ * vma_flags_t read_flags = vma_flags_and(&flags, VMA_READ_BIT,
+ * VMA_MAY_READ_BIT);
*/
-#define mk_vma_flags(...) __mk_vma_flags(COUNT_ARGS(__VA_ARGS__), \
- (const vma_flag_t []){__VA_ARGS__})
+#define vma_flags_and(flags, ...) \
+ vma_flags_and_mask(flags, mk_vma_flags(__VA_ARGS__))
/* Test each of to_test flags in flags, non-atomically. */
static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags,
#define vma_flags_clear(flags, ...) \
vma_flags_clear_mask(flags, mk_vma_flags(__VA_ARGS__))
+/*
+ * Obtain a VMA flags value containing those flags that are present in flags or
+ * flags_other but not in both.
+ */
+static __always_inline vma_flags_t vma_flags_diff_pair(const vma_flags_t *flags,
+ const vma_flags_t *flags_other)
+{
+ vma_flags_t dst;
+ const unsigned long *bitmap_other = flags_other->__vma_flags;
+ const unsigned long *bitmap = flags->__vma_flags;
+ unsigned long *bitmap_dst = dst.__vma_flags;
+
+ bitmap_xor(bitmap_dst, bitmap, bitmap_other, NUM_VMA_FLAG_BITS);
+ return dst;
+}
+
/*
* Helper to test that ALL specified flags are set in a VMA.
*
#define EMPTY_VMA_FLAGS ((vma_flags_t){ })
+/* Are no flags set in the specified VMA flags? */
+static __always_inline bool vma_flags_empty(const vma_flags_t *flags)
+{
+ const unsigned long *bitmap = flags->__vma_flags;
+
+ return bitmap_empty(bitmap, NUM_VMA_FLAG_BITS);
+}
+
/*
* Describes a VMA that is about to be mmap()'ed. Drivers may choose to
* manipulate mutable fields which will cause those fields to be updated in the
const unsigned long *bitmap2, unsigned int nbits);
bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, unsigned int nbits);
+void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
else
__bitmap_clear(map, start, nbits);
}
+
+static __always_inline
+void bitmap_xor(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ *dst = *src1 ^ *src2;
+ else
+ __bitmap_xor(dst, src1, src2, nbits);
+}
+
#endif /* _TOOLS_LINUX_BITMAP_H */
return false;
return true;
}
+
+void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int bits)
+{
+ unsigned int k;
+ unsigned int nr = BITS_TO_LONGS(bits);
+
+ for (k = 0; k < nr; k++)
+ dst[k] = bitmap1[k] ^ bitmap2[k];
+}
#define MAPCOUNT_ELF_CORE_MARGIN (5)
#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
+static __always_inline bool vma_flags_empty(const vma_flags_t *flags)
+{
+ const unsigned long *bitmap = flags->__vma_flags;
+
+ return bitmap_empty(bitmap, NUM_VMA_FLAG_BITS);
+}
+
/* What action should be taken after an .mmap_prepare call is complete? */
enum mmap_action_type {
MMAP_NOTHING, /* Mapping is complete, no further action. */
return test_bit((__force int)bit, bitmap);
}
+static __always_inline vma_flags_t vma_flags_and_mask(const vma_flags_t *flags,
+ vma_flags_t to_and)
+{
+ vma_flags_t dst;
+ unsigned long *bitmap_dst = dst.__vma_flags;
+ const unsigned long *bitmap = flags->__vma_flags;
+ const unsigned long *bitmap_to_and = to_and.__vma_flags;
+
+ bitmap_and(bitmap_dst, bitmap, bitmap_to_and, NUM_VMA_FLAG_BITS);
+ return dst;
+}
+
+#define vma_flags_and(flags, ...) \
+ vma_flags_and_mask(flags, mk_vma_flags(__VA_ARGS__))
+
static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags,
vma_flags_t to_test)
{
#define vma_flags_clear(flags, ...) \
vma_flags_clear_mask(flags, mk_vma_flags(__VA_ARGS__))
+static __always_inline vma_flags_t vma_flags_diff_pair(const vma_flags_t *flags,
+ const vma_flags_t *flags_other)
+{
+ vma_flags_t dst;
+ const unsigned long *bitmap_other = flags_other->__vma_flags;
+ const unsigned long *bitmap = flags->__vma_flags;
+ unsigned long *bitmap_dst = dst.__vma_flags;
+
+ bitmap_xor(bitmap_dst, bitmap, bitmap_other, NUM_VMA_FLAG_BITS);
+ return dst;
+}
+
static inline bool vma_test_all_mask(const struct vm_area_struct *vma,
- vma_flags_t flags)
+ vma_flags_t flags)
{
return vma_flags_test_all_mask(&vma->flags, flags);
}
projects / thirdparty / kernel / linux.git / commitdiff
