[PATCH v3 -next 6/9] PPC, KVM, CMA: use general CMA reserved area management framework

Joonsoo Kim
2014-06-16T05:40:48Z

Now, we have general CMA reserved area management framework,
so use it for future maintainabilty. There is no functional change.

v3: add zeroing to CMA region (Aneesh)
fix compile error (Aneesh)
move VM_BUG_ON() to kvm_alloc_hpt() in book3s_hv_builtin.c (Aneesh)

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 8056107..a41e625 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -37,8 +37,6 @@
#include <asm/ppc-opcode.h>
#include <asm/cputable.h>

-#include "book3s_hv_cma.h"
-
/* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */
#define MAX_LPID_970 63

@@ -64,10 +62,10 @@ long kvmppc_alloc_hpt(struct kvm *kvm, u32 *htab_orderp)
}

kvm->arch.hpt_cma_alloc = 0;
- VM_BUG_ON(order < KVM_CMA_CHUNK_ORDER);
page = kvm_alloc_hpt(1 << (order - PAGE_SHIFT));
if (page) {
hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page));
+ memset((void *)hpt, 0, (1 << order));
kvm->arch.hpt_cma_alloc = 1;
}

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 7cde8a6..3960e0b 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -16,12 +16,14 @@
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/sizes.h>
+#include <linux/cma.h>

#include <asm/cputable.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>

-#include "book3s_hv_cma.h"
+#define KVM_CMA_CHUNK_ORDER 18
+
/*
* Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
* should be power of 2.
@@ -43,6 +45,8 @@ static unsigned long kvm_cma_resv_ratio = 5;
unsigned long kvm_rma_pages = (1 << 27) >> PAGE_SHIFT; /* 128MB */
EXPORT_SYMBOL_GPL(kvm_rma_pages);

+static struct cma *kvm_cma;
+
/* Work out RMLS (real mode limit selector) field value for a given RMA size.
Assumes POWER7 or PPC970. */
static inline int lpcr_rmls(unsigned long rma_size)
@@ -97,7 +101,7 @@ struct kvm_rma_info *kvm_alloc_rma()
ri = kmalloc(sizeof(struct kvm_rma_info), GFP_KERNEL);
if (!ri)
return NULL;
- page = kvm_alloc_cma(kvm_rma_pages, kvm_rma_pages);
+ page = cma_alloc(kvm_cma, kvm_rma_pages, get_order(kvm_rma_pages));
if (!page)
goto err_out;
atomic_set(&ri->use_count, 1);
@@ -112,7 +116,7 @@ EXPORT_SYMBOL_GPL(kvm_alloc_rma);
void kvm_release_rma(struct kvm_rma_info *ri)
{
if (atomic_dec_and_test(&ri->use_count)) {
- kvm_release_cma(pfn_to_page(ri->base_pfn), kvm_rma_pages);
+ cma_release(kvm_cma, pfn_to_page(ri->base_pfn), kvm_rma_pages);
kfree(ri);
}
}
@@ -131,16 +135,18 @@ struct page *kvm_alloc_hpt(unsigned long nr_pages)
{
unsigned long align_pages = HPT_ALIGN_PAGES;

+ VM_BUG_ON(get_order(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
+
/* Old CPUs require HPT aligned on a multiple of its size */
if (!cpu_has_feature(CPU_FTR_ARCH_206))
align_pages = nr_pages;
- return kvm_alloc_cma(nr_pages, align_pages);
+ return cma_alloc(kvm_cma, nr_pages, get_order(align_pages));
}
EXPORT_SYMBOL_GPL(kvm_alloc_hpt);

void kvm_release_hpt(struct page *page, unsigned long nr_pages)
{
- kvm_release_cma(page, nr_pages);
+ cma_release(kvm_cma, page, nr_pages);
}
EXPORT_SYMBOL_GPL(kvm_release_hpt);

@@ -179,7 +185,8 @@ void __init kvm_cma_reserve(void)
align_size = HPT_ALIGN_PAGES << PAGE_SHIFT;

align_size = max(kvm_rma_pages << PAGE_SHIFT, align_size);
- kvm_cma_declare_contiguous(selected_size, align_size);
+ cma_declare_contiguous(selected_size, 0, 0, align_size,
+ KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, &kvm_cma, false);
}
}

diff --git a/arch/powerpc/kvm/book3s_hv_cma.c b/arch/powerpc/kvm/book3s_hv_cma.c
deleted file mode 100644
index d9d3d85..0000000
--- a/arch/powerpc/kvm/book3s_hv_cma.c
+++ /dev/null
@@ -1,240 +0,0 @@
-/*
- * Contiguous Memory Allocator for ppc KVM hash pagetable based on CMA
- * for DMA mapping framework
- *
- * Copyright IBM Corporation, 2013
- * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License or (at your optional) any later version of the license.
- *
- */
-#define pr_fmt(fmt) "kvm_cma: " fmt
-
-#ifdef CONFIG_CMA_DEBUG
-#ifndef DEBUG
-# define DEBUG
-#endif
-#endif
-
-#include <linux/memblock.h>
-#include <linux/mutex.h>
-#include <linux/sizes.h>
-#include <linux/slab.h>
-
-#include "book3s_hv_cma.h"
-
-struct kvm_cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
-};
-
-static DEFINE_MUTEX(kvm_cma_mutex);
-static struct kvm_cma kvm_cma_area;
-
-/**
- * kvm_cma_declare_contiguous() - reserve area for contiguous memory handling
- * for kvm hash pagetable
- * @size: Size of the reserved memory.
- * @alignment: Alignment for the contiguous memory area
- *
- * This function reserves memory for kvm cma area. It should be
- * called by arch code when early allocator (memblock or bootmem)
- * is still activate.
- */
-long __init kvm_cma_declare_contiguous(phys_addr_t size, phys_addr_t alignment)
-{
- long base_pfn;
- phys_addr_t addr;
- struct kvm_cma *cma = &kvm_cma_area;
-
- pr_debug("%s(size %lx)\n", __func__, (unsigned long)size);
-
- if (!size)
- return -EINVAL;
- /*
- * Sanitise input arguments.
- * We should be pageblock aligned for CMA.
- */
- alignment = max(alignment, (phys_addr_t)(PAGE_SIZE << pageblock_order));
- size = ALIGN(size, alignment);
- /*
- * Reserve memory
- * Use __memblock_alloc_base() since
- * memblock_alloc_base() panic()s.
- */
- addr = __memblock_alloc_base(size, alignment, 0);
- if (!addr) {
- base_pfn = -ENOMEM;
- goto err;
- } else
- base_pfn = PFN_DOWN(addr);
-
- /*
- * Each reserved area must be initialised later, when more kernel
- * subsystems (like slab allocator) are available.
- */
- cma->base_pfn = base_pfn;
- cma->count = size >> PAGE_SHIFT;
- pr_info("CMA: reserved %ld MiB\n", (unsigned long)size / SZ_1M);
- return 0;
-err:
- pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
- return base_pfn;
-}
-
-/**
- * kvm_alloc_cma() - allocate pages from contiguous area
- * @nr_pages: Requested number of pages.
- * @align_pages: Requested alignment in number of pages
- *
- * This function allocates memory buffer for hash pagetable.
- */
-struct page *kvm_alloc_cma(unsigned long nr_pages, unsigned long align_pages)
-{
- int ret;
- struct page *page = NULL;
- struct kvm_cma *cma = &kvm_cma_area;
- unsigned long chunk_count, nr_chunk;
- unsigned long mask, pfn, pageno, start = 0;
-
-
- if (!cma || !cma->count)
- return NULL;
-
- pr_debug("%s(cma %p, count %lu, align pages %lu)\n", __func__,
- (void *)cma, nr_pages, align_pages);
-
- if (!nr_pages)
- return NULL;
- /*
- * align mask with chunk size. The bit tracks pages in chunk size
- */
- VM_BUG_ON(!is_power_of_2(align_pages));
- mask = (align_pages >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT)) - 1;
- BUILD_BUG_ON(PAGE_SHIFT > KVM_CMA_CHUNK_ORDER);
-
- chunk_count = cma->count >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
- nr_chunk = nr_pages >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
-
- mutex_lock(&kvm_cma_mutex);
- for (;;) {
- pageno = bitmap_find_next_zero_area(cma->bitmap, chunk_count,
- start, nr_chunk, mask);
- if (pageno >= chunk_count)
- break;
-
- pfn = cma->base_pfn + (pageno << (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT));
- ret = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_CMA);
- if (ret == 0) {
- bitmap_set(cma->bitmap, pageno, nr_chunk);
- page = pfn_to_page(pfn);
- memset(pfn_to_kaddr(pfn), 0, nr_pages << PAGE_SHIFT);
- break;
- } else if (ret != -EBUSY) {
- break;
- }
- pr_debug("%s(): memory range@%p is busy, retrying\n",
- __func__, pfn_to_page(pfn));
- /* try again with a bit different memory target */
- start = pageno + mask + 1;
- }
- mutex_unlock(&kvm_cma_mutex);
- pr_debug("%s(): returned %p\n", __func__, page);
- return page;
-}
-
-/**
- * kvm_release_cma() - release allocated pages for hash pagetable
- * @pages: Allocated pages.
- * @nr_pages: Number of allocated pages.
- *
- * This function releases memory allocated by kvm_alloc_cma().
- * It returns false when provided pages do not belong to contiguous area and
- * true otherwise.
- */
-bool kvm_release_cma(struct page *pages, unsigned long nr_pages)
-{
- unsigned long pfn;
- unsigned long nr_chunk;
- struct kvm_cma *cma = &kvm_cma_area;
-
- if (!cma || !pages)
- return false;
-
- pr_debug("%s(page %p count %lu)\n", __func__, (void *)pages, nr_pages);
-
- pfn = page_to_pfn(pages);
-
- if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count)
- return false;
-
- VM_BUG_ON(pfn + nr_pages > cma->base_pfn + cma->count);
- nr_chunk = nr_pages >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
-
- mutex_lock(&kvm_cma_mutex);
- bitmap_clear(cma->bitmap,
- (pfn - cma->base_pfn) >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT),
- nr_chunk);
- free_contig_range(pfn, nr_pages);
- mutex_unlock(&kvm_cma_mutex);
-
- return true;
-}
-
-static int __init kvm_cma_activate_area(unsigned long base_pfn,
- unsigned long count)
-{
- unsigned long pfn = base_pfn;
- unsigned i = count >> pageblock_order;
- struct zone *zone;
-
- WARN_ON_ONCE(!pfn_valid(pfn));
- zone = page_zone(pfn_to_page(pfn));
- do {
- unsigned j;
- base_pfn = pfn;
- for (j = pageblock_nr_pages; j; --j, pfn++) {
- WARN_ON_ONCE(!pfn_valid(pfn));
- /*
- * alloc_contig_range requires the pfn range
- * specified to be in the same zone. Make this
- * simple by forcing the entire CMA resv range
- * to be in the same zone.
- */
- if (page_zone(pfn_to_page(pfn)) != zone)
- return -EINVAL;
- }
- init_cma_reserved_pageblock(pfn_to_page(base_pfn));
- } while (--i);
- return 0;
-}
-
-static int __init kvm_cma_init_reserved_areas(void)
-{
- int bitmap_size, ret;
- unsigned long chunk_count;
- struct kvm_cma *cma = &kvm_cma_area;
-
- pr_debug("%s()\n", __func__);
- if (!cma->count)
- return 0;
- chunk_count = cma->count >> (KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
- bitmap_size = BITS_TO_LONGS(chunk_count) * sizeof(long);
- cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma->bitmap)
- return -ENOMEM;
-
- ret = kvm_cma_activate_area(cma->base_pfn, cma->count);
- if (ret)
- goto error;
- return 0;
-
-error:
- kfree(cma->bitmap);
- return ret;
-}
-core_initcall(kvm_cma_init_reserved_areas);
diff --git a/arch/powerpc/kvm/book3s_hv_cma.h b/arch/powerpc/kvm/book3s_hv_cma.h
deleted file mode 100644
index 655144f..0000000
--- a/arch/powerpc/kvm/book3s_hv_cma.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/*
- * Contiguous Memory Allocator for ppc KVM hash pagetable based on CMA
- * for DMA mapping framework
- *
- * Copyright IBM Corporation, 2013
- * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License or (at your optional) any later version of the license.
- *
- */
-
-#ifndef __POWERPC_KVM_CMA_ALLOC_H__
-#define __POWERPC_KVM_CMA_ALLOC_H__
-/*
- * Both RMA and Hash page allocation will be multiple of 256K.
- */
-#define KVM_CMA_CHUNK_ORDER 18
-
-extern struct page *kvm_alloc_cma(unsigned long nr_pages,
- unsigned long align_pages);
-extern bool kvm_release_cma(struct page *pages, unsigned long nr_pages);
-extern long kvm_cma_declare_contiguous(phys_addr_t size,
- phys_addr_t alignment) __init;
-#endif
--
1.7.9.5