mm: update all remaining mmap_prepare users to use vma_flags_t

ljskernel · akpm00 · commit 5bd2c0650a90 · 2026-02-12T15:42:58.000-08:00
We will be shortly removing the vm_flags_t field from vm_area_desc so we need to update all mmap_prepare users to only use the dessc->vma_flags field. This patch achieves that and makes all ancillary changes required to make this possible. This lays the groundwork for future work to eliminate the use of vm_flags_t in vm_area_desc altogether and more broadly throughout the kernel. While we're here, we take the opportunity to replace VM_REMAP_FLAGS with VMA_REMAP_FLAGS, the vma_flags_t equivalent. No functional changes intended. Link: https://lkml.kernel.org/r/fb1f55323799f09fe6a36865b31550c9ec67c225.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Damien Le Moal <dlemoal@kernel.org> [zonefs] Acked-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Pedro Falcato <pfalcato@suse.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
@@ -306,7 +306,7 @@ static unsigned zero_mmap_capabilities(struct file *file)
 /* can't do an in-place private mapping if there's no MMU */
 static inline int private_mapping_ok(struct vm_area_desc *desc)
 {
-	return is_nommu_shared_mapping(desc->vm_flags);
+	return is_nommu_shared_vma_flags(&desc->vma_flags);
 }
 #else
 
@@ -360,7 +360,7 @@ static int mmap_mem_prepare(struct vm_area_desc *desc)
 
 	desc->vm_ops = &mmap_mem_ops;
 
-	/* Remap-pfn-range will mark the range VM_IO. */
+	/* Remap-pfn-range will mark the range with the I/O flag. */
 	mmap_action_remap_full(desc, desc->pgoff);
 	/* We filter remap errors to -EAGAIN. */
 	desc->action.error_hook = mmap_filter_error;
@@ -520,7 +520,7 @@ static int mmap_zero_prepare(struct vm_area_desc *desc)
 #ifndef CONFIG_MMU
 	return -ENOSYS;
 #endif
-	if (desc->vm_flags & VM_SHARED)
+	if (vma_desc_test_flags(desc, VMA_SHARED_BIT))
 		return shmem_zero_setup_desc(desc);
 
 	desc->action.success_hook = mmap_zero_private_success;
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
@@ -13,7 +13,7 @@
 #include "dax-private.h"
 #include "bus.h"
 
-static int __check_vma(struct dev_dax *dev_dax, vm_flags_t vm_flags,
+static int __check_vma(struct dev_dax *dev_dax, vma_flags_t flags,
 		       unsigned long start, unsigned long end, struct file *file,
 		       const char *func)
 {
@@ -24,7 +24,7 @@ static int __check_vma(struct dev_dax *dev_dax, vm_flags_t vm_flags,
 		return -ENXIO;
 
 	/* prevent private mappings from being established */
-	if ((vm_flags & VM_MAYSHARE) != VM_MAYSHARE) {
+	if (!vma_flags_test(&flags, VMA_MAYSHARE_BIT)) {
 		dev_info_ratelimited(dev,
 				"%s: %s: fail, attempted private mapping\n",
 				current->comm, func);
@@ -53,7 +53,7 @@ static int __check_vma(struct dev_dax *dev_dax, vm_flags_t vm_flags,
 static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
 		     const char *func)
 {
-	return __check_vma(dev_dax, vma->vm_flags, vma->vm_start, vma->vm_end,
+	return __check_vma(dev_dax, vma->flags, vma->vm_start, vma->vm_end,
 			   vma->vm_file, func);
 }
 
@@ -306,14 +306,14 @@ static int dax_mmap_prepare(struct vm_area_desc *desc)
 	 * fault time.
 	 */
 	id = dax_read_lock();
-	rc = __check_vma(dev_dax, desc->vm_flags, desc->start, desc->end, filp,
+	rc = __check_vma(dev_dax, desc->vma_flags, desc->start, desc->end, filp,
 			 __func__);
 	dax_read_unlock(id);
 	if (rc)
 		return rc;
 
 	desc->vm_ops = &dax_vm_ops;
-	desc->vm_flags |= VM_HUGEPAGE;
+	vma_desc_set_flags(desc, VMA_HUGEPAGE_BIT);
 	return 0;
 }
 
diff --git a/fs/aio.c b/fs/aio.c
@@ -394,7 +394,7 @@ static const struct vm_operations_struct aio_ring_vm_ops = {
 
 static int aio_ring_mmap_prepare(struct vm_area_desc *desc)
 {
-	desc->vm_flags |= VM_DONTEXPAND;
+	vma_desc_set_flags(desc, VMA_DONTEXPAND_BIT);
 	desc->vm_ops = &aio_ring_vm_ops;
 	return 0;
 }
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
@@ -438,11 +438,12 @@ static int erofs_file_mmap_prepare(struct vm_area_desc *desc)
 	if (!IS_DAX(file_inode(desc->file)))
 		return generic_file_readonly_mmap_prepare(desc);
 
-	if ((desc->vm_flags & VM_SHARED) && (desc->vm_flags & VM_MAYWRITE))
+	if (vma_desc_test_flags(desc, VMA_SHARED_BIT) &&
+	    vma_desc_test_flags(desc, VMA_MAYWRITE_BIT))
 		return -EINVAL;
 
 	desc->vm_ops = &erofs_dax_vm_ops;
-	desc->vm_flags |= VM_HUGEPAGE;
+	vma_desc_set_flags(desc, VMA_HUGEPAGE_BIT);
 	return 0;
 }
 #else
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
@@ -822,13 +822,13 @@ static int ext4_file_mmap_prepare(struct vm_area_desc *desc)
 	 * We don't support synchronous mappings for non-DAX files and
 	 * for DAX files if underneath dax_device is not synchronous.
 	 */
-	if (!daxdev_mapping_supported(desc->vm_flags, file_inode(file), dax_dev))
+	if (!daxdev_mapping_supported(desc, file_inode(file), dax_dev))
 		return -EOPNOTSUPP;
 
 	file_accessed(file);
 	if (IS_DAX(file_inode(file))) {
 		desc->vm_ops = &ext4_dax_vm_ops;
-		desc->vm_flags |= VM_HUGEPAGE;
+		vma_desc_set_flags(desc, VMA_HUGEPAGE_BIT);
 	} else {
 		desc->vm_ops = &ext4_file_vm_ops;
 	}
diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
@@ -347,7 +347,7 @@ static int ntfs_file_mmap_prepare(struct vm_area_desc *desc)
 	struct inode *inode = file_inode(file);
 	struct ntfs_inode *ni = ntfs_i(inode);
 	u64 from = ((u64)desc->pgoff << PAGE_SHIFT);
-	bool rw = desc->vm_flags & VM_WRITE;
+	const bool rw = vma_desc_test_flags(desc, VMA_WRITE_BIT);
 	int err;
 
 	/* Avoid any operation if inode is bad. */
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
@@ -411,8 +411,8 @@ static int orangefs_file_mmap_prepare(struct vm_area_desc *desc)
 		     "orangefs_file_mmap: called on %pD\n", file);
 
 	/* set the sequential readahead hint */
-	desc->vm_flags |= VM_SEQ_READ;
-	desc->vm_flags &= ~VM_RAND_READ;
+	vma_desc_set_flags(desc, VMA_SEQ_READ_BIT);
+	vma_desc_clear_flags(desc, VMA_RAND_READ_BIT);
 
 	file_accessed(file);
 	desc->vm_ops = &orangefs_file_vm_ops;
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
@@ -264,7 +264,7 @@ static unsigned long ramfs_nommu_get_unmapped_area(struct file *file,
  */
 static int ramfs_nommu_mmap_prepare(struct vm_area_desc *desc)
 {
-	if (!is_nommu_shared_mapping(desc->vm_flags))
+	if (!is_nommu_shared_vma_flags(&desc->vma_flags))
 		return -ENOSYS;
 
 	file_accessed(desc->file);
diff --git a/fs/resctrl/pseudo_lock.c b/fs/resctrl/pseudo_lock.c
@@ -1044,7 +1044,7 @@ static int pseudo_lock_dev_mmap_prepare(struct vm_area_desc *desc)
 	 * Ensure changes are carried directly to the memory being mapped,
 	 * do not allow copy-on-write mapping.
 	 */
-	if (!(desc->vm_flags & VM_SHARED)) {
+	if (!vma_desc_test_flags(desc, VMA_SHARED_BIT)) {
 		mutex_unlock(&rdtgroup_mutex);
 		return -EINVAL;
 	}
diff --git a/fs/romfs/mmap-nommu.c b/fs/romfs/mmap-nommu.c
@@ -63,7 +63,7 @@ static unsigned long romfs_get_unmapped_area(struct file *file,
  */
 static int romfs_mmap_prepare(struct vm_area_desc *desc)
 {
-	return is_nommu_shared_mapping(desc->vm_flags) ? 0 : -ENOSYS;
+	return is_nommu_shared_vma_flags(&desc->vma_flags) ? 0 : -ENOSYS;
 }
 
 static unsigned romfs_mmap_capabilities(struct file *file)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
@@ -1974,14 +1974,14 @@ xfs_file_mmap_prepare(
 	 * We don't support synchronous mappings for non-DAX files and
 	 * for DAX files if underneath dax_device is not synchronous.
 	 */
-	if (!daxdev_mapping_supported(desc->vm_flags, file_inode(file),
+	if (!daxdev_mapping_supported(desc, file_inode(file),
 				      target->bt_daxdev))
 		return -EOPNOTSUPP;
 
 	file_accessed(file);
 	desc->vm_ops = &xfs_file_vm_ops;
 	if (IS_DAX(inode))
-		desc->vm_flags |= VM_HUGEPAGE;
+		vma_desc_set_flags(desc, VMA_HUGEPAGE_BIT);
 	return 0;
 }
 
diff --git a/fs/zonefs/file.c b/fs/zonefs/file.c
@@ -333,7 +333,8 @@ static int zonefs_file_mmap_prepare(struct vm_area_desc *desc)
 	 * ordering between msync() and page cache writeback.
 	 */
 	if (zonefs_inode_is_seq(file_inode(file)) &&
-	    (desc->vm_flags & VM_SHARED) && (desc->vm_flags & VM_MAYWRITE))
+	    vma_desc_test_flags(desc, VMA_SHARED_BIT) &&
+	    vma_desc_test_flags(desc, VMA_MAYWRITE_BIT))
 		return -EINVAL;
 
 	file_accessed(file);
diff --git a/include/linux/dax.h b/include/linux/dax.h
@@ -65,11 +65,11 @@ size_t dax_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff,
 /*
  * Check if given mapping is supported by the file / underlying device.
  */
-static inline bool daxdev_mapping_supported(vm_flags_t vm_flags,
+static inline bool daxdev_mapping_supported(const struct vm_area_desc *desc,
 					    const struct inode *inode,
 					    struct dax_device *dax_dev)
 {
-	if (!(vm_flags & VM_SYNC))
+	if (!vma_desc_test_flags(desc, VMA_SYNC_BIT))
 		return true;
 	if (!IS_DAX(inode))
 		return false;
@@ -111,11 +111,11 @@ static inline void set_dax_nomc(struct dax_device *dax_dev)
 static inline void set_dax_synchronous(struct dax_device *dax_dev)
 {
 }
-static inline bool daxdev_mapping_supported(vm_flags_t vm_flags,
+static inline bool daxdev_mapping_supported(const struct vm_area_desc *desc,
 					    const struct inode *inode,
 					    struct dax_device *dax_dev)
 {
-	return !(vm_flags & VM_SYNC);
+	return !vma_desc_test_flags(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
@@ -550,17 +550,18 @@ enum {
 /*
  * Physically remapped pages are special. Tell the
  * rest of the world about it:
- *   VM_IO tells people not to look at these pages
+ *   IO tells people not to look at these pages
  *	(accesses can have side effects).
- *   VM_PFNMAP tells the core MM that the base pages are just
+ *   PFNMAP tells the core MM that the base pages are just
  *	raw PFN mappings, and do not have a "struct page" associated
  *	with them.
- *   VM_DONTEXPAND
+ *   DONTEXPAND
  *      Disable vma merging and expanding with mremap().
- *   VM_DONTDUMP
+ *   DONTDUMP
  *      Omit vma from core dump, even when VM_IO turned off.
  */
-#define VM_REMAP_FLAGS (VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP)
+#define VMA_REMAP_FLAGS mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT,	\
+				     VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT)
 
 /* This mask prevents VMA from being scanned with khugepaged */
 #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
@@ -1925,6 +1926,14 @@ static inline bool is_cow_mapping(vm_flags_t flags)
 	return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
 }
 
+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);
+}
+
 #ifndef CONFIG_MMU
 static inline bool is_nommu_shared_mapping(vm_flags_t flags)
 {
@@ -1938,6 +1947,11 @@ static inline bool is_nommu_shared_mapping(vm_flags_t flags)
 	 */
 	return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
 }
+
+static inline bool is_nommu_shared_vma_flags(const vma_flags_t *flags)
+{
+	return vma_flags_test(flags, VMA_MAYSHARE_BIT, VMA_MAYOVERLAY_BIT);
+}
 #endif
 
 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
diff --git a/kernel/relay.c b/kernel/relay.c
@@ -92,7 +92,7 @@ static int relay_mmap_prepare_buf(struct rchan_buf *buf,
 		return -EINVAL;
 
 	desc->vm_ops = &relay_file_mmap_ops;
-	desc->vm_flags |= VM_DONTEXPAND;
+	vma_desc_set_flags(desc, VMA_DONTEXPAND_BIT);
 	desc->private_data = buf;
 
 	return 0;
diff --git a/mm/memory.c b/mm/memory.c
@@ -2957,7 +2957,7 @@ static inline int remap_p4d_range(struct mm_struct *mm, pgd_t *pgd,
 	return 0;
 }
 
-static int get_remap_pgoff(vm_flags_t vm_flags, unsigned long addr,
+static int get_remap_pgoff(bool is_cow, unsigned long addr,
 		unsigned long end, unsigned long vm_start, unsigned long vm_end,
 		unsigned long pfn, pgoff_t *vm_pgoff_p)
 {
@@ -2967,7 +2967,7 @@ static int get_remap_pgoff(vm_flags_t vm_flags, unsigned long addr,
 	 * un-COW'ed pages by matching them up with "vma->vm_pgoff".
 	 * See vm_normal_page() for details.
 	 */
-	if (is_cow_mapping(vm_flags)) {
+	if (is_cow) {
 		if (addr != vm_start || end != vm_end)
 			return -EINVAL;
 		*vm_pgoff_p = pfn;
@@ -2988,7 +2988,7 @@ static int remap_pfn_range_internal(struct vm_area_struct *vma, unsigned long ad
 	if (WARN_ON_ONCE(!PAGE_ALIGNED(addr)))
 		return -EINVAL;
 
-	VM_WARN_ON_ONCE((vma->vm_flags & VM_REMAP_FLAGS) != VM_REMAP_FLAGS);
+	VM_WARN_ON_ONCE(!vma_test_all_flags_mask(vma, VMA_REMAP_FLAGS));
 
 	BUG_ON(addr >= end);
 	pfn -= addr >> PAGE_SHIFT;
@@ -3112,9 +3112,9 @@ void remap_pfn_range_prepare(struct vm_area_desc *desc, unsigned long pfn)
 	 * check it again on complete and will fail there if specified addr is
 	 * invalid.
 	 */
-	get_remap_pgoff(desc->vm_flags, desc->start, desc->end,
+	get_remap_pgoff(vma_desc_is_cow_mapping(desc), desc->start, desc->end,
 			desc->start, desc->end, pfn, &desc->pgoff);
-	desc->vm_flags |= VM_REMAP_FLAGS;
+	vma_desc_set_flags_mask(desc, VMA_REMAP_FLAGS);
 }
 
 static int remap_pfn_range_prepare_vma(struct vm_area_struct *vma, unsigned long addr,
@@ -3123,13 +3123,12 @@ static int remap_pfn_range_prepare_vma(struct vm_area_struct *vma, unsigned long
 	unsigned long end = addr + PAGE_ALIGN(size);
 	int err;
 
-	err = get_remap_pgoff(vma->vm_flags, addr, end,
-			      vma->vm_start, vma->vm_end,
-			      pfn, &vma->vm_pgoff);
+	err = get_remap_pgoff(is_cow_mapping(vma->vm_flags), addr, end,
+			      vma->vm_start, vma->vm_end, pfn, &vma->vm_pgoff);
 	if (err)
 		return err;
 
-	vm_flags_set(vma, VM_REMAP_FLAGS);
+	vma_set_flags_mask(vma, VMA_REMAP_FLAGS);
 	return 0;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -394,7 +394,7 @@ static const struct vm_operations_struct aio_ring_vm_ops = {`
`394`	`394`
`395`	`395`	`static int aio_ring_mmap_prepare(struct vm_area_desc *desc)`
`396`	`396`	`{`
`397`		`- desc->vm_flags \|= VM_DONTEXPAND;`
	`397`	`+ vma_desc_set_flags(desc, VMA_DONTEXPAND_BIT);`
`398`	`398`	`desc->vm_ops = &aio_ring_vm_ops;`
`399`	`399`	`return 0;`
`400`	`400`	`}`
Original file line number	Diff line number	Diff line change
`@@ -264,7 +264,7 @@ static unsigned long ramfs_nommu_get_unmapped_area(struct file *file,`
`264`	`264`	`*/`
`265`	`265`	`static int ramfs_nommu_mmap_prepare(struct vm_area_desc *desc)`
`266`	`266`	`{`
`267`		`- if (!is_nommu_shared_mapping(desc->vm_flags))`
	`267`	`+ if (!is_nommu_shared_vma_flags(&desc->vma_flags))`
`268`	`268`	`return -ENOSYS;`
`269`	`269`
`270`	`270`	`file_accessed(desc->file);`
Original file line number	Diff line number	Diff line change
`@@ -1044,7 +1044,7 @@ static int pseudo_lock_dev_mmap_prepare(struct vm_area_desc *desc)`
`1044`	`1044`	`* Ensure changes are carried directly to the memory being mapped,`
`1045`	`1045`	`* do not allow copy-on-write mapping.`
`1046`	`1046`	`*/`
`1047`		`- if (!(desc->vm_flags & VM_SHARED)) {`
	`1047`	`+ if (!vma_desc_test_flags(desc, VMA_SHARED_BIT)) {`
`1048`	`1048`	`mutex_unlock(&rdtgroup_mutex);`
`1049`	`1049`	`return -EINVAL;`
`1050`	`1050`	`}`
Original file line number	Diff line number	Diff line change
`@@ -63,7 +63,7 @@ static unsigned long romfs_get_unmapped_area(struct file *file,`
`63`	`63`	`*/`
`64`	`64`	`static int romfs_mmap_prepare(struct vm_area_desc *desc)`
`65`	`65`	`{`
`66`		`- return is_nommu_shared_mapping(desc->vm_flags) ? 0 : -ENOSYS;`
	`66`	`+ return is_nommu_shared_vma_flags(&desc->vma_flags) ? 0 : -ENOSYS;`
`67`	`67`	`}`
`68`	`68`
`69`	`69`	`static unsigned romfs_mmap_capabilities(struct file *file)`