mm: unify module_alloc code for vmalloc

Four architectures (arm, mips, sparc, x86) use __vmalloc_area() for
module_init().  Much of the code is duplicated and can be generalized in a
globally accessible function, __vmalloc_node_range().

__vmalloc_node() now calls into __vmalloc_node_range() with a range of
[VMALLOC_START, VMALLOC_END) for functionally equivalent behavior.

Each architecture may then use __vmalloc_node_range() directly to remove
the duplication of code.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 46 insertions, 68 deletions

diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index 0c1bb68ff4a8..2cfe8161b478 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -38,17 +38,9 @@
 #ifdef CONFIG_MMU
 void *module_alloc(unsigned long size)
 {
-        struct vm_struct *area;
-
-        size = PAGE_ALIGN(size);
-        if (!size)
-                return NULL;
-
-        area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
-        if (!area)
-                return NULL;
-
-        return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
+        return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+                                GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
+                                __builtin_return_address(0));
 }
 #else /* CONFIG_MMU */
 void *module_alloc(unsigned long size)
diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
index 6f51dda87fce..d87a72e9fac7 100644
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -46,17 +46,9 @@ static DEFINE_SPINLOCK(dbe_lock);
 void *module_alloc(unsigned long size)
 {
 #ifdef MODULE_START
-        struct vm_struct *area;
-
-        size = PAGE_ALIGN(size);
-        if (!size)
-                return NULL;
-
-        area = __get_vm_area(size, VM_ALLOC, MODULE_START, MODULE_END);
-        if (!area)
-                return NULL;
-
-        return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL);
+        return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
+                                GFP_KERNEL, PAGE_KERNEL, -1,
+                                __builtin_return_address(0));
 #else
         if (size == 0)
                 return NULL;
diff --git a/arch/sparc/kernel/module.c b/arch/sparc/kernel/module.c
index ee3c7dde8d9f..8d348c474a2f 100644
--- a/arch/sparc/kernel/module.c
+++ b/arch/sparc/kernel/module.c
@@ -23,17 +23,11 @@
 
 static void *module_map(unsigned long size)
 {
-        struct vm_struct *area;
-
-        size = PAGE_ALIGN(size);
-        if (!size || size > MODULES_LEN)
-                return NULL;
-
-        area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
-        if (!area)
+        if (PAGE_ALIGN(size) > MODULES_LEN)
                 return NULL;
-
-        return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL);
+        return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+                                GFP_KERNEL, PAGE_KERNEL, -1,
+                                __builtin_return_address(0));
 }
 
 static char *dot2underscore(char *name)
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 8f2956091735..ab23f1ad4bf1 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -37,20 +37,11 @@
 
 void *module_alloc(unsigned long size)
 {
-        struct vm_struct *area;
-
-        if (!size)
-                return NULL;
-        size = PAGE_ALIGN(size);
-        if (size > MODULES_LEN)
+        if (PAGE_ALIGN(size) > MODULES_LEN)
                 return NULL;
-
-        area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
-        if (!area)
-                return NULL;
-
-        return __vmalloc_area(area, GFP_KERNEL | __GFP_HIGHMEM,
-                                        PAGE_KERNEL_EXEC);
+        return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+                                GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
+                                -1, __builtin_return_address(0));
 }
 
 /* Free memory returned from module_alloc */
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index c7348b8d0a81..4ed6fcd6b726 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -59,8 +59,9 @@ extern void *vmalloc_exec(unsigned long size);
 extern void *vmalloc_32(unsigned long size);
 extern void *vmalloc_32_user(unsigned long size);
 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
-extern void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask,
-                                pgprot_t prot);
+extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
+                        unsigned long start, unsigned long end, gfp_t gfp_mask,
+                        pgprot_t prot, int node, void *caller);
 extern void vfree(const void *addr);
 
 extern void *vmap(struct page **pages, unsigned int count,
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f67546636322..284346ee0e91 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1530,25 +1530,12 @@ fail:
         return NULL;
 }
 
-void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot)
-{
-        void *addr = __vmalloc_area_node(area, gfp_mask, prot, -1,
-                                         __builtin_return_address(0));
-
-        /*
-         * A ref_count = 3 is needed because the vm_struct and vmap_area
-         * structures allocated in the __get_vm_area_node() function contain
-         * references to the virtual address of the vmalloc'ed block.
-         */
-        kmemleak_alloc(addr, area->size - PAGE_SIZE, 3, gfp_mask);
-
-        return addr;
-}
-
 /**
- *      __vmalloc_node  -  allocate virtually contiguous memory
+ *      __vmalloc_node_range  -  allocate virtually contiguous memory
  *      @size:          allocation size
  *      @align:         desired alignment
+ *      @start:         vm area range start
+ *      @end:           vm area range end
  *      @gfp_mask:      flags for the page level allocator
  *      @prot:          protection mask for the allocated pages
  *      @node:          node to use for allocation or -1
@@ -1558,9 +1545,9 @@ void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot)
  *      allocator with @gfp_mask flags.  Map them into contiguous
  *      kernel virtual space, using a pagetable protection of @prot.
  */
-static void *__vmalloc_node(unsigned long size, unsigned long align,
-                            gfp_t gfp_mask, pgprot_t prot,
-                            int node, void *caller)
+void *__vmalloc_node_range(unsigned long size, unsigned long align,
+                        unsigned long start, unsigned long end, gfp_t gfp_mask,
+                        pgprot_t prot, int node, void *caller)
 {
         struct vm_struct *area;
         void *addr;
@@ -1570,8 +1557,8 @@ static void *__vmalloc_node(unsigned long size, unsigned long align,
         if (!size || (size >> PAGE_SHIFT) > totalram_pages)
                 return NULL;
 
-        area = __get_vm_area_node(size, align, VM_ALLOC, VMALLOC_START,
-                                  VMALLOC_END, node, gfp_mask, caller);
+        area = __get_vm_area_node(size, align, VM_ALLOC, start, end, node,
+                                  gfp_mask, caller);
 
         if (!area)
                 return NULL;
@@ -1588,6 +1575,27 @@ static void *__vmalloc_node(unsigned long size, unsigned long align,
         return addr;
 }
 
+/**
+ *      __vmalloc_node  -  allocate virtually contiguous memory
+ *      @size:          allocation size
+ *      @align:         desired alignment
+ *      @gfp_mask:      flags for the page level allocator
+ *      @prot:          protection mask for the allocated pages
+ *      @node:          node to use for allocation or -1
+ *      @caller:        caller's return address
+ *
+ *      Allocate enough pages to cover @size from the page level
+ *      allocator with @gfp_mask flags.  Map them into contiguous
+ *      kernel virtual space, using a pagetable protection of @prot.
+ */
+static void *__vmalloc_node(unsigned long size, unsigned long align,
+                            gfp_t gfp_mask, pgprot_t prot,
+                            int node, void *caller)
+{
+        return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
+                                gfp_mask, prot, node, caller);
+}
+
 void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
 {
         return __vmalloc_node(size, 1, gfp_mask, prot, -1,