mm: reintroduce vma_desc_test() as a singular flag test

Similar to vma_flags_test(), we have previously renamed vma_desc_test() to
vma_desc_test_any().  Now that is in place, we can reintroduce
vma_desc_test() to explicitly check for a single VMA flag.

As with vma_flags_test(), this is useful as often flag tests are against a
single flag, and vma_desc_test_any(flags, VMA_READ_BIT) reads oddly and
potentially causes confusion.

As with vma_flags_test() a combination of sparse and vma_flags_t being a
struct means that users cannot misuse this function without it getting
flagged.

Also update the VMA tests to reflect this change.

Link: https://lkml.kernel.org/r/3a65ca23defb05060333f0586428fe279a484564.1772704455.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
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>

2 files changed, 13 insertions, 2 deletions

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 535019001577..10a7cc79aea5 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_any(desc, VMA_SYNC_BIT))
+	if (!vma_desc_test(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_any(desc, VMA_SYNC_BIT);
+	return !vma_desc_test(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/mm.h b/include/linux/mm.h
index 9392723a5c50..63d1f619260e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1192,6 +1192,17 @@ static inline void vma_set_flags_mask(struct vm_area_struct *vma,
 #define vma_set_flags(vma, ...) \
 	vma_set_flags_mask(vma, mk_vma_flags(__VA_ARGS__))
 
+/*
+ * Test whether a specific VMA flag is set in a VMA descriptor, e.g.:
+ *
+ * if (vma_desc_test(desc, VMA_READ_BIT)) { ... }
+ */
+static __always_inline bool vma_desc_test(const struct vm_area_desc *desc,
+		vma_flag_t bit)
+{
+	return vma_flags_test(&desc->vma_flags, bit);
+}
+
 /* Helper to test any VMA flags in a VMA descriptor. */
 static inline bool vma_desc_test_any_mask(const struct vm_area_desc *desc,
 		vma_flags_t flags)