mm: move anon_vma declarations to linux/mm_inline.h

The patch to add anonymous vma names causes a build failure in some
configurations:

  include/linux/mm_types.h: In function 'is_same_vma_anon_name':
  include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration]
    924 |         return name && vma_name && !strcmp(name, vma_name);
        |                                     ^~~~~~
  include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'?

This should not really be part of linux/mm_types.h in the first place,
as that header is meant to only contain structure defintions and need a
minimum set of indirect includes itself.

While the header clearly includes more than it should at this point,
let's not make it worse by including string.h as well, which would pull
in the expensive (compile-speed wise) fortify-string logic.

Move the new functions into a separate header that only needs to be
included in a couple of locations.

Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org
Fixes: "mm: add a field to store names for private anonymous memory"
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Colin Cross <ccross@google.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e6998652fd67fee5e690ad1d0280752d41a4ebad..18f8c3acbb85e8a90bf9a5395042bf5975987ae9 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/pagewalk.h>
 #include <linux/vmacache.h>
+#include <linux/mm_inline.h>
 #include <linux/hugetlb.h>
 #include <linux/huge_mm.h>
 #include <linux/mount.h>

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 5b2af7b8277633db409dde2213d36bb50afa199e..e26b10132d47e2a49edf6da88ad109ea3141b657 100644 (file)
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -15,6 +15,7 @@
 #include <linux/sched/signal.h>
 #include <linux/sched/mm.h>
 #include <linux/mm.h>
+#include <linux/mm_inline.h>
 #include <linux/mmu_notifier.h>
 #include <linux/poll.h>
 #include <linux/slab.h>

diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index e2ec68b0515c5bc2794a584f869f1d62bc210a07..47d96d2647cae569d85f4a79567888ee5c358a88 100644 (file)
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -4,6 +4,7 @@
 
 #include <linux/huge_mm.h>
 #include <linux/swap.h>
+#include <linux/string.h>
 
 /**
  * folio_is_file_lru - Should the folio be on a file LRU or anon LRU?
@@ -135,4 +136,53 @@ static __always_inline void del_page_from_lru_list(struct page *page,
 {
        lruvec_del_folio(lruvec, page_folio(page));
 }
+
+#ifdef CONFIG_ANON_VMA_NAME
+/*
+ * mmap_lock should be read-locked when calling vma_anon_name() and while using
+ * the returned pointer.
+ */
+extern const char *vma_anon_name(struct vm_area_struct *vma);
+
+/*
+ * mmap_lock should be read-locked for orig_vma->vm_mm.
+ * mmap_lock should be write-locked for new_vma->vm_mm or new_vma should be
+ * isolated.
+ */
+extern void dup_vma_anon_name(struct vm_area_struct *orig_vma,
+                             struct vm_area_struct *new_vma);
+
+/*
+ * mmap_lock should be write-locked or vma should have been isolated under
+ * write-locked mmap_lock protection.
+ */
+extern void free_vma_anon_name(struct vm_area_struct *vma);
+
+/* mmap_lock should be read-locked */
+static inline bool is_same_vma_anon_name(struct vm_area_struct *vma,
+                                        const char *name)
+{
+       const char *vma_name = vma_anon_name(vma);
+
+       /* either both NULL, or pointers to same string */
+       if (vma_name == name)
+               return true;
+
+       return name && vma_name && !strcmp(name, vma_name);
+}
+#else /* CONFIG_ANON_VMA_NAME */
+static inline const char *vma_anon_name(struct vm_area_struct *vma)
+{
+       return NULL;
+}
+static inline void dup_vma_anon_name(struct vm_area_struct *orig_vma,
+                             struct vm_area_struct *new_vma) {}
+static inline void free_vma_anon_name(struct vm_area_struct *vma) {}
+static inline bool is_same_vma_anon_name(struct vm_area_struct *vma,
+                                        const char *name)
+{
+       return true;
+}
+#endif  /* CONFIG_ANON_VMA_NAME */
+
 #endif

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 449b6eafc695d438848a3e5544608ecc83910cf1..4d5fb84eed5eec1ff0ac6d9c5a685564dd4eca03 100644 (file)
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -890,52 +890,4 @@ typedef struct {
        unsigned long val;
 } swp_entry_t;
 
-#ifdef CONFIG_ANON_VMA_NAME
-/*
- * mmap_lock should be read-locked when calling vma_anon_name() and while using
- * the returned pointer.
- */
-extern const char *vma_anon_name(struct vm_area_struct *vma);
-
-/*
- * mmap_lock should be read-locked for orig_vma->vm_mm.
- * mmap_lock should be write-locked for new_vma->vm_mm or new_vma should be
- * isolated.
- */
-extern void dup_vma_anon_name(struct vm_area_struct *orig_vma,
-                             struct vm_area_struct *new_vma);
-
-/*
- * mmap_lock should be write-locked or vma should have been isolated under
- * write-locked mmap_lock protection.
- */
-extern void free_vma_anon_name(struct vm_area_struct *vma);
-
-/* mmap_lock should be read-locked */
-static inline bool is_same_vma_anon_name(struct vm_area_struct *vma,
-                                        const char *name)
-{
-       const char *vma_name = vma_anon_name(vma);
-
-       /* either both NULL, or pointers to same string */
-       if (vma_name == name)
-               return true;
-
-       return name && vma_name && !strcmp(name, vma_name);
-}
-#else /* CONFIG_ANON_VMA_NAME */
-static inline const char *vma_anon_name(struct vm_area_struct *vma)
-{
-       return NULL;
-}
-static inline void dup_vma_anon_name(struct vm_area_struct *orig_vma,
-                             struct vm_area_struct *new_vma) {}
-static inline void free_vma_anon_name(struct vm_area_struct *vma) {}
-static inline bool is_same_vma_anon_name(struct vm_area_struct *vma,
-                                        const char *name)
-{
-       return true;
-}
-#endif  /* CONFIG_ANON_VMA_NAME */
-
 #endif /* _LINUX_MM_TYPES_H */

diff --git a/kernel/fork.c b/kernel/fork.c
index 4cf20b5f2da34c8e32bf78f8e8ac59880163bc60..75737e566441215f4ac7808d598a7fe6346e6acb 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -42,6 +42,7 @@
 #include <linux/mmu_notifier.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/mm_inline.h>
 #include <linux/vmacache.h>
 #include <linux/nsproxy.h>
 #include <linux/capability.h>

diff --git a/mm/madvise.c b/mm/madvise.c
index c63aacbbfa788a549db3c726d2cc54a096a9fc57..5604064df4646e786d1c9e2fcf0a35eb71f622ba 100644 (file)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -18,6 +18,7 @@
 #include <linux/fadvise.h>
 #include <linux/sched.h>
 #include <linux/sched/mm.h>
+#include <linux/mm_inline.h>
 #include <linux/string.h>
 #include <linux/uio.h>
 #include <linux/ksm.h>

diff --git a/mm/mmap.c b/mm/mmap.c
index 85edb0011453ddf120af0559475ec6e9df6716a8..77733b113c40cf2b96c0c7c5f14d1ada5ed9250e 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/backing-dev.h>
 #include <linux/mm.h>
+#include <linux/mm_inline.h>
 #include <linux/vmacache.h>
 #include <linux/shm.h>
 #include <linux/mman.h>