[PATCH 26/29] mm: remove vmalloc_user_node_flags

From: Christoph Hellwig
Date: Tue Apr 14 2020 - 09:16:57 EST


Open code it in __bpf_map_area_alloc, which is the only caller. Also
clean up __bpf_map_area_alloc to have a single vmalloc call with
slightly different flags instead of the current two different calls.

For this to compile for the nommu case add a __vmalloc_node_range stub
to nommu.c.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
---
include/linux/vmalloc.h | 1 -
kernel/bpf/syscall.c | 24 ++++++++++++++----------
mm/nommu.c | 14 ++++++++------
mm/vmalloc.c | 20 --------------------
4 files changed, 22 insertions(+), 37 deletions(-)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 108f49b47756..f90f2946aac2 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -106,7 +106,6 @@ extern void *vzalloc(unsigned long size);
extern void *vmalloc_user(unsigned long size);
extern void *vmalloc_node(unsigned long size, int node);
extern void *vzalloc_node(unsigned long size, int node);
-extern void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags);
extern void *vmalloc_exec(unsigned long size);
extern void *vmalloc_32(unsigned long size);
extern void *vmalloc_32_user(unsigned long size);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 48d98ea8fad6..dd30b334c554 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -25,6 +25,7 @@
#include <linux/nospec.h>
#include <linux/audit.h>
#include <uapi/linux/btf.h>
+#include <asm/pgtable.h>
#include <linux/bpf_lsm.h>

#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
@@ -281,26 +282,29 @@ static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
* __GFP_RETRY_MAYFAIL to avoid such situations.
*/

- const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
+ const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO;
+ unsigned int flags = 0;
+ unsigned long align = 1;
void *area;

if (size >= SIZE_MAX)
return NULL;

/* kmalloc()'ed memory can't be mmap()'ed */
- if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
- area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
+ if (mmapable) {
+ BUG_ON(!PAGE_ALIGNED(size));
+ align = SHMLBA;
+ flags = VM_USERMAP;
+ } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
+ area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
numa_node);
if (area != NULL)
return area;
}
- if (mmapable) {
- BUG_ON(!PAGE_ALIGNED(size));
- return vmalloc_user_node_flags(size, numa_node, GFP_KERNEL |
- __GFP_RETRY_MAYFAIL | flags);
- }
- return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_RETRY_MAYFAIL | flags,
- numa_node, __builtin_return_address(0));
+
+ return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
+ gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
+ flags, numa_node, __builtin_return_address(0));
}

void *bpf_map_area_alloc(u64 size, int numa_node)
diff --git a/mm/nommu.c b/mm/nommu.c
index 81a86cd85893..b42cd6003d7d 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -150,6 +150,14 @@ void *__vmalloc(unsigned long size, gfp_t gfp_mask)
}
EXPORT_SYMBOL(__vmalloc);

+void *__vmalloc_node_range(unsigned long size, unsigned long align,
+ unsigned long start, unsigned long end, gfp_t gfp_mask,
+ pgprot_t prot, unsigned long vm_flags, int node,
+ const void *caller)
+{
+ return __vmalloc(size, flags);
+}
+
void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
int node, const void *caller)
{
@@ -180,12 +188,6 @@ void *vmalloc_user(unsigned long size)
}
EXPORT_SYMBOL(vmalloc_user);

-void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags)
-{
- return __vmalloc_user_flags(size, flags | __GFP_ZERO);
-}
-EXPORT_SYMBOL(vmalloc_user_node_flags);
-
struct page *vmalloc_to_page(const void *addr)
{
return virt_to_page(addr);
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 333fbe77255a..f6f2acdaf70c 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2658,26 +2658,6 @@ void *vzalloc_node(unsigned long size, int node)
}
EXPORT_SYMBOL(vzalloc_node);

-/**
- * vmalloc_user_node_flags - allocate memory for userspace on a specific node
- * @size: allocation size
- * @node: numa node
- * @flags: flags for the page level allocator
- *
- * The resulting memory area is zeroed so it can be mapped to userspace
- * without leaking data.
- *
- * Return: pointer to the allocated memory or %NULL on error
- */
-void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags)
-{
- return __vmalloc_node_range(size, SHMLBA, VMALLOC_START, VMALLOC_END,
- flags | __GFP_ZERO, PAGE_KERNEL,
- VM_USERMAP, node,
- __builtin_return_address(0));
-}
-EXPORT_SYMBOL(vmalloc_user_node_flags);
-
/**
* vmalloc_exec - allocate virtually contiguous, executable memory
* @size: allocation size
--
2.25.1