mm: rename VMA flag helpers to be more readable

Patch series "mm: vma flag tweaks".

The ongoing work around introducing non-system word VMA flags has
introduced a number of helper functions and macros to make life easier
when working with these flags and to make conversions from the legacy use
of VM_xxx flags more straightforward.

This series improves these to reduce confusion as to what they do and to
improve consistency and readability.

Firstly the series renames vma_flags_test() to vma_flags_test_any() to
make it abundantly clear that this function tests whether any of the flags
are set (as opposed to vma_flags_test_all()).

It then renames vma_desc_test_flags() to vma_desc_test_any() for the same
reason.  Note that we drop the 'flags' suffix here, as
vma_desc_test_any_flags() would be cumbersome and 'test' implies a flag
test.

Similarly, we rename vma_test_all_flags() to vma_test_all() for
consistency.

Next, we have a couple of instances (erofs, zonefs) where we are now
testing for vma_desc_test_any(desc, VMA_SHARED_BIT) &&
vma_desc_test_any(desc, VMA_MAYWRITE_BIT).

This is silly, so this series introduces vma_desc_test_all() so these
callers can instead invoke vma_desc_test_all(desc, VMA_SHARED_BIT,
VMA_MAYWRITE_BIT).

We then observe that quite a few instances of vma_flags_test_any() and
vma_desc_test_any() are in fact only testing against a single flag.

Using the _any() variant here is just confusing - 'any' of single item
reads strangely and is liable to cause confusion.

So in these instances the series reintroduces vma_flags_test() and
vma_desc_test() as helpers which test against a single flag.

The fact that vma_flags_t is a struct and that vma_flag_t utilises sparse
to avoid confusion with vm_flags_t makes it impossible for a user to
misuse these helpers without it getting flagged somewhere.

The series also updates __mk_vma_flags() and functions invoked by it to
explicitly mark them always inline to match expectation and to be
consistent with other VMA flag helpers.

It also renames vma_flag_set() to vma_flags_set_flag() (a function only
used by __mk_vma_flags()) to be consistent with other VMA flag helpers.

Finally it updates the VMA tests for each of these changes, and introduces
explicit tests for vma_flags_test() and vma_desc_test() to assert that
they behave as expected.


This patch (of 6):

On reflection, it's confusing to have vma_flags_test() and
vma_desc_test_flags() test whether any comma-separated VMA flag bit is
set, while also having vma_flags_test_all() and vma_test_all_flags()
separately test whether all flags are set.

Firstly, rename vma_flags_test() to vma_flags_test_any() to eliminate this
confusion.

Secondly, since the VMA descriptor flag functions are becoming rather
cumbersome, prefer vma_desc_test*() to vma_desc_test_flags*(), and also
rename vma_desc_test_flags() to vma_desc_test_any().

Finally, rename vma_test_all_flags() to vma_test_all() to keep the
VMA-specific helper consistent with the VMA descriptor naming convention
and to help avoid confusion vs.  vma_flags_test_all().

While we're here, also update whitespace to be consistent in helper
functions.

Link: https://lkml.kernel.org/r/cover.1772704455.git.ljs@kernel.org
Link: https://lkml.kernel.org/r/0f9cb3c511c478344fac0b3b3b0300bb95be95e9.1772704455.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Suggested-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Babu Moger <babu.moger@amd.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Chatre, Reinette <reinette.chatre@intel.com>
Cc: Chunhai Guo <guochunhai@vivo.com>
Cc: Damien Le Maol <dlemoal@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hongbo Li <lihongbo22@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naohiro Aota <naohiro.aota@wdc.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Yue Hu <zbestahu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

3 files changed, 28 insertions, 26 deletions

diff --git a/include/linux/dax.h b/include/linux/dax.h
index bf103f317cac..535019001577 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -69,7 +69,7 @@ static inline bool daxdev_mapping_supported(const struct vm_area_desc *desc,
 					    const struct inode *inode,
 					    struct dax_device *dax_dev)
 {
-	if (!vma_desc_test_flags(desc, VMA_SYNC_BIT))
+	if (!vma_desc_test_any(desc, VMA_SYNC_BIT))
 		return true;
 	if (!IS_DAX(inode))
 		return false;
@@ -115,7 +115,7 @@ static inline bool daxdev_mapping_supported(const struct vm_area_desc *desc,
 					    const struct inode *inode,
 					    struct dax_device *dax_dev)
 {
-	return !vma_desc_test_flags(desc, VMA_SYNC_BIT);
+	return !vma_desc_test_any(desc, VMA_SYNC_BIT);
 }
 static inline size_t dax_recovery_write(struct dax_device *dax_dev,
 		pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i)
diff --git a/include/linux/hugetlb_inline.h b/include/linux/hugetlb_inline.h
index 593f5d4e108b..84afc3c3e2e4 100644
--- a/include/linux/hugetlb_inline.h
+++ b/include/linux/hugetlb_inline.h
@@ -13,7 +13,7 @@ static inline bool is_vm_hugetlb_flags(vm_flags_t vm_flags)
 
 static inline bool is_vma_hugetlb_flags(const vma_flags_t *flags)
 {
-	return vma_flags_test(flags, VMA_HUGETLB_BIT);
+	return vma_flags_test_any(flags, VMA_HUGETLB_BIT);
 }
 
 #else
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c516d5177211..ee7671d6c5eb 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1062,7 +1062,7 @@ static inline vma_flags_t __mk_vma_flags(size_t count, const vma_flag_t *bits)
 					 (const vma_flag_t []){__VA_ARGS__})
 
 /*  Test each of to_test flags in flags, non-atomically. */
-static __always_inline bool vma_flags_test_mask(const vma_flags_t *flags,
+static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags,
 		vma_flags_t to_test)
 {
 	const unsigned long *bitmap = flags->__vma_flags;
@@ -1074,10 +1074,10 @@ static __always_inline bool vma_flags_test_mask(const vma_flags_t *flags,
 /*
  * Test whether any specified VMA flag is set, e.g.:
  *
- * if (vma_flags_test(flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { ... }
+ * if (vma_flags_test_any(flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { ... }
  */
-#define vma_flags_test(flags, ...) \
-	vma_flags_test_mask(flags, mk_vma_flags(__VA_ARGS__))
+#define vma_flags_test_any(flags, ...) \
+	vma_flags_test_any_mask(flags, mk_vma_flags(__VA_ARGS__))
 
 /* Test that ALL of the to_test flags are set, non-atomically. */
 static __always_inline bool vma_flags_test_all_mask(const vma_flags_t *flags,
@@ -1098,7 +1098,8 @@ static __always_inline bool vma_flags_test_all_mask(const vma_flags_t *flags,
 	vma_flags_test_all_mask(flags, mk_vma_flags(__VA_ARGS__))
 
 /* Set each of the to_set flags in flags, non-atomically. */
-static __always_inline void vma_flags_set_mask(vma_flags_t *flags, vma_flags_t to_set)
+static __always_inline void vma_flags_set_mask(vma_flags_t *flags,
+		vma_flags_t to_set)
 {
 	unsigned long *bitmap = flags->__vma_flags;
 	const unsigned long *bitmap_to_set = to_set.__vma_flags;
@@ -1115,7 +1116,8 @@ static __always_inline void vma_flags_set_mask(vma_flags_t *flags, vma_flags_t t
 	vma_flags_set_mask(flags, mk_vma_flags(__VA_ARGS__))
 
 /* Clear all of the to-clear flags in flags, non-atomically. */
-static __always_inline void vma_flags_clear_mask(vma_flags_t *flags, vma_flags_t to_clear)
+static __always_inline void vma_flags_clear_mask(vma_flags_t *flags,
+		vma_flags_t to_clear)
 {
 	unsigned long *bitmap = flags->__vma_flags;
 	const unsigned long *bitmap_to_clear = to_clear.__vma_flags;
@@ -1137,8 +1139,8 @@ static __always_inline void vma_flags_clear_mask(vma_flags_t *flags, vma_flags_t
  * Note: appropriate locks must be held, this function does not acquire them for
  * you.
  */
-static inline bool vma_test_all_flags_mask(const struct vm_area_struct *vma,
-					   vma_flags_t flags)
+static inline bool vma_test_all_mask(const struct vm_area_struct *vma,
+		vma_flags_t flags)
 {
 	return vma_flags_test_all_mask(&vma->flags, flags);
 }
@@ -1146,10 +1148,10 @@ static inline bool vma_test_all_flags_mask(const struct vm_area_struct *vma,
 /*
  * Helper macro for checking that ALL specified flags are set in a VMA, e.g.:
  *
- * if (vma_test_all_flags(vma, VMA_READ_BIT, VMA_MAYREAD_BIT) { ... }
+ * if (vma_test_all(vma, VMA_READ_BIT, VMA_MAYREAD_BIT) { ... }
  */
-#define vma_test_all_flags(vma, ...) \
-	vma_test_all_flags_mask(vma, mk_vma_flags(__VA_ARGS__))
+#define vma_test_all(vma, ...) \
+	vma_test_all_mask(vma, mk_vma_flags(__VA_ARGS__))
 
 /*
  * Helper to set all VMA flags in a VMA.
@@ -1158,7 +1160,7 @@ static inline bool vma_test_all_flags_mask(const struct vm_area_struct *vma,
  * you.
  */
 static inline void vma_set_flags_mask(struct vm_area_struct *vma,
-				      vma_flags_t flags)
+		vma_flags_t flags)
 {
 	vma_flags_set_mask(&vma->flags, flags);
 }
@@ -1176,25 +1178,25 @@ static inline void vma_set_flags_mask(struct vm_area_struct *vma,
 	vma_set_flags_mask(vma, mk_vma_flags(__VA_ARGS__))
 
 /* Helper to test all VMA flags in a VMA descriptor. */
-static inline bool vma_desc_test_flags_mask(const struct vm_area_desc *desc,
-					    vma_flags_t flags)
+static inline bool vma_desc_test_any_mask(const struct vm_area_desc *desc,
+		vma_flags_t flags)
 {
-	return vma_flags_test_mask(&desc->vma_flags, flags);
+	return vma_flags_test_any_mask(&desc->vma_flags, flags);
 }
 
 /*
  * Helper macro for testing VMA flags for an input pointer to a struct
  * vm_area_desc object describing a proposed VMA, e.g.:
  *
- * if (vma_desc_test_flags(desc, VMA_IO_BIT, VMA_PFNMAP_BIT,
+ * if (vma_desc_test_any(desc, VMA_IO_BIT, VMA_PFNMAP_BIT,
  *		VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT)) { ... }
  */
-#define vma_desc_test_flags(desc, ...) \
-	vma_desc_test_flags_mask(desc, mk_vma_flags(__VA_ARGS__))
+#define vma_desc_test_any(desc, ...) \
+	vma_desc_test_any_mask(desc, mk_vma_flags(__VA_ARGS__))
 
 /* Helper to set all VMA flags in a VMA descriptor. */
 static inline void vma_desc_set_flags_mask(struct vm_area_desc *desc,
-					   vma_flags_t flags)
+		vma_flags_t flags)
 {
 	vma_flags_set_mask(&desc->vma_flags, flags);
 }
@@ -1211,7 +1213,7 @@ static inline void vma_desc_set_flags_mask(struct vm_area_desc *desc,
 
 /* Helper to clear all VMA flags in a VMA descriptor. */
 static inline void vma_desc_clear_flags_mask(struct vm_area_desc *desc,
-					     vma_flags_t flags)
+		vma_flags_t flags)
 {
 	vma_flags_clear_mask(&desc->vma_flags, flags);
 }
@@ -1936,8 +1938,8 @@ static inline bool vma_desc_is_cow_mapping(struct vm_area_desc *desc)
 {
 	const vma_flags_t *flags = &desc->vma_flags;
 
-	return vma_flags_test(flags, VMA_MAYWRITE_BIT) &&
-		!vma_flags_test(flags, VMA_SHARED_BIT);
+	return vma_flags_test_any(flags, VMA_MAYWRITE_BIT) &&
+		!vma_flags_test_any(flags, VMA_SHARED_BIT);
 }
 
 #ifndef CONFIG_MMU
@@ -1956,7 +1958,7 @@ static inline bool is_nommu_shared_mapping(vm_flags_t flags)
 
 static inline bool is_nommu_shared_vma_flags(const vma_flags_t *flags)
 {
-	return vma_flags_test(flags, VMA_MAYSHARE_BIT, VMA_MAYOVERLAY_BIT);
+	return vma_flags_test_any(flags, VMA_MAYSHARE_BIT, VMA_MAYOVERLAY_BIT);
 }
 #endif