Commit 5e6d45d7 authored by Lorenzo Stoakes (Oracle)'s avatar Lorenzo Stoakes (Oracle) Committed by Andrew Morton
Browse files

mm: reintroduce vma_flags_test() as a singular flag test 

Since we've now renamed vma_flags_test() to vma_flags_test_any() to be
very clear as to what we are in fact testing, we now have the opportunity
to bring vma_flags_test() back, but for explicitly testing a single VMA
flag.

This is useful, as often flag tests are against a single flag, and
vma_flags_test_any(flags, VMA_READ_BIT) reads oddly and potentially causes
confusion.

We use sparse to enforce that users won't accidentally pass vm_flags_t to
this function without it being flagged so this should make it harder to
get this wrong.

Of course, passing vma_flags_t to the function is impossible, as it is a
struct.

Also update the VMA tests to reflect this change.

Link: https://lkml.kernel.org/r/f33f8d7f16c3f3d286a1dc2cba12c23683073134.1772704455.git.ljs@kernel.org


Signed-off-by: default avatarLorenzo Stoakes (Oracle) <ljs@kernel.org>
Acked-by: default avatarDavid Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: default avatarPedro 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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent a5eee112

include/linux/mm.h

+15 −2
Original line number Diff line number Diff line
@@ -1050,6 +1050,19 @@ static __always_inline vma_flags_t __mk_vma_flags(size_t count, 
	return flags;

}



/*

 * Test whether a specific VMA flag is set, e.g.:

 *

 * if (vma_flags_test(flags, VMA_READ_BIT)) { ... }

 */

static __always_inline bool vma_flags_test(const vma_flags_t *flags,

		vma_flag_t bit)

{

	const unsigned long *bitmap = flags->__vma_flags;



	return test_bit((__force int)bit, bitmap);

}



/*

 * Helper macro which bitwise-or combines the specified input flags into a

 * vma_flags_t bitmap value. E.g.:
@@ -1956,8 +1969,8 @@ 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_any(flags, VMA_MAYWRITE_BIT) &&

		!vma_flags_test_any(flags, VMA_SHARED_BIT);

	return vma_flags_test(flags, VMA_MAYWRITE_BIT) &&

		!vma_flags_test(flags, VMA_SHARED_BIT);

}



#ifndef CONFIG_MMU

mm/hugetlb.c

+1 −1
Original line number Diff line number Diff line
@@ -6593,7 +6593,7 @@ long hugetlb_reserve_pages(struct inode *inode, 
	 * attempt will be made for VM_NORESERVE to allocate a page

	 * without using reserves

	 */

	if (vma_flags_test_any(&vma_flags, VMA_NORESERVE_BIT))

	if (vma_flags_test(&vma_flags, VMA_NORESERVE_BIT))

		return 0;



	/*

mm/shmem.c

+2 −2
Original line number Diff line number Diff line
@@ -3086,7 +3086,7 @@ static struct inode *__shmem_get_inode(struct mnt_idmap *idmap, 
	spin_lock_init(&info->lock);

	atomic_set(&info->stop_eviction, 0);

	info->seals = F_SEAL_SEAL;

	info->flags = vma_flags_test_any(&flags, VMA_NORESERVE_BIT)

	info->flags = vma_flags_test(&flags, VMA_NORESERVE_BIT)

		? SHMEM_F_NORESERVE : 0;

	info->i_crtime = inode_get_mtime(inode);

	info->fsflags = (dir == NULL) ? 0 :
@@ -5827,7 +5827,7 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, 
				       unsigned int i_flags)

{

	const unsigned long shmem_flags =

		vma_flags_test_any(&flags, VMA_NORESERVE_BIT) ? SHMEM_F_NORESERVE : 0;

		vma_flags_test(&flags, VMA_NORESERVE_BIT) ? SHMEM_F_NORESERVE : 0;

	struct inode *inode;

	struct file *res;

tools/testing/vma/include/dup.h

+8 −0
Original line number Diff line number Diff line
@@ -844,6 +844,14 @@ static inline vma_flags_t __mk_vma_flags(size_t count, const vma_flag_t *bits); 
#define mk_vma_flags(...) __mk_vma_flags(COUNT_ARGS(__VA_ARGS__), \

					 (const vma_flag_t []){__VA_ARGS__})



static __always_inline bool vma_flags_test(const vma_flags_t *flags,

		vma_flag_t bit)

{

	const unsigned long *bitmap = flags->__vma_flags;



	return test_bit((__force int)bit, bitmap);

}



static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags,

		vma_flags_t to_test)

{