@@ -854,10 +854,8 @@ config HAVE_ARCH_HUGE_VMAP
#
# Archs that select this would be capable of PMD-sized vmaps (i.e.,
-# arch_vmap_pmd_supported() returns true), and they must make no assumptions
-# that vmalloc memory is mapped with PAGE_SIZE ptes. The VM_NO_HUGE_VMAP flag
-# can be used to prohibit arch-specific allocations from using hugepages to
-# help with this (e.g., modules may require it).
+# arch_vmap_pmd_supported() returns true). The VM_ALLOW_HUGE_VMAP flag
+# must be used to enable allocations to use hugepages.
#
config HAVE_ARCH_HUGE_VMALLOC
depends on HAVE_ARCH_HUGE_VMAP
@@ -101,7 +101,7 @@ __module_alloc(unsigned long size, unsigned long start, unsigned long end, bool
* too.
*/
return __vmalloc_node_range(size, 1, start, end, gfp, prot,
- VM_FLUSH_RESET_PERMS | VM_NO_HUGE_VMAP,
+ VM_FLUSH_RESET_PERMS,
NUMA_NO_NODE, __builtin_return_address(0));
}
@@ -137,12 +137,7 @@ static int kvm_s390_pv_alloc_vm(struct kvm *kvm)
/* Allocate variable storage */
vlen = ALIGN(virt * ((npages * PAGE_SIZE) / HPAGE_SIZE), PAGE_SIZE);
vlen += uv_info.guest_virt_base_stor_len;
- /*
- * The Create Secure Configuration Ultravisor Call does not support
- * using large pages for the virtual memory area.
- * This is a hardware limitation.
- */
- kvm->arch.pv.stor_var = vmalloc_no_huge(vlen);
+ kvm->arch.pv.stor_var = vzalloc(vlen);
if (!kvm->arch.pv.stor_var)
goto out_err;
return 0;
@@ -26,7 +26,7 @@ struct notifier_block; /* in notifier.h */
#define VM_KASAN 0x00000080 /* has allocated kasan shadow memory */
#define VM_FLUSH_RESET_PERMS 0x00000100 /* reset direct map and flush TLB on unmap, can't be freed in atomic context */
#define VM_MAP_PUT_PAGES 0x00000200 /* put pages and free array in vfree */
-#define VM_NO_HUGE_VMAP 0x00000400 /* force PAGE_SIZE pte mapping */
+#define VM_ALLOW_HUGE_VMAP 0x00000400 /* Allow for huge pages on archs with HAVE_ARCH_HUGE_VMALLOC */
#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
!defined(CONFIG_KASAN_VMALLOC)
@@ -153,7 +153,7 @@ extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
const void *caller) __alloc_size(1);
void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
int node, const void *caller) __alloc_size(1);
-void *vmalloc_no_huge(unsigned long size) __alloc_size(1);
+void *vmalloc_huge(unsigned long size, gfp_t gfp_mask) __alloc_size(1);
extern void *__vmalloc_array(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);
extern void *vmalloc_array(size_t n, size_t size) __alloc_size(1, 2);
@@ -3106,7 +3106,7 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
return NULL;
}
- if (vmap_allow_huge && !(vm_flags & VM_NO_HUGE_VMAP)) {
+ if (vmap_allow_huge && (vm_flags & VM_ALLOW_HUGE_VMAP)) {
unsigned long size_per_node;
/*
@@ -3273,21 +3273,24 @@ void *vmalloc(unsigned long size)
EXPORT_SYMBOL(vmalloc);
/**
- * vmalloc_no_huge - allocate virtually contiguous memory using small pages
- * @size: allocation size
+ * vmalloc_huge - allocate virtually contiguous memory, allow huge pages
+ * @size: allocation size
+ * @gfp_mask: flags for the page level allocator
*
- * Allocate enough non-huge pages to cover @size from the page level
+ * Allocate enough pages to cover @size from the page level
* allocator and map them into contiguous kernel virtual space.
+ * If @size is greater than or equal to PMD_SIZE, allow using
+ * huge pages for the memory
*
* Return: pointer to the allocated memory or %NULL on error
*/
-void *vmalloc_no_huge(unsigned long size)
+void *vmalloc_huge(unsigned long size, gfp_t gfp_mask)
{
return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL, PAGE_KERNEL, VM_NO_HUGE_VMAP,
+ gfp_mask, PAGE_KERNEL, VM_ALLOW_HUGE_VMAP,
NUMA_NO_NODE, __builtin_return_address(0));
}
-EXPORT_SYMBOL(vmalloc_no_huge);
+EXPORT_SYMBOL_GPL(vmalloc_huge);
/**
* vzalloc - allocate virtually contiguous memory with zero fill
Huge page backed vmalloc memory could benefit performance in many cases. However, some users of vmalloc may not be ready to handle huge pages for various reasons: hardware constraints, potential pages split, etc. VM_NO_HUGE_VMAP was introduced to allow vmalloc users to opt-out huge pages. However, it is not easy to track down all the users that require the opt-out, as the allocation are passed different stacks and may cause issues in different layers. To address this issue, replace VM_NO_HUGE_VMAP with an opt-in flag, VM_ALLOW_HUGE_VMAP, so that users that benefit from huge pages could ask specificially. Also, remove vmalloc_no_huge() and add opt-in helpers vmalloc_huge(). Fixes: fac54e2bfb5b ("x86/Kconfig: Select HAVE_ARCH_HUGE_VMALLOC with HAVE_ARCH_HUGE_VMAP") Link: https://lore.kernel.org/netdev/14444103-d51b-0fb3-ee63-c3f182f0b546@molgen.mpg.de/" Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> --- arch/Kconfig | 6 ++---- arch/powerpc/kernel/module.c | 2 +- arch/s390/kvm/pv.c | 7 +------ include/linux/vmalloc.h | 4 ++-- mm/vmalloc.c | 17 ++++++++++------- 5 files changed, 16 insertions(+), 20 deletions(-)