[PATCH v3 1/3] mm/hugetlb: Allow arch to override and call the weak function

@@ -358,6 +358,7 @@ int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
 			pgoff_t idx);
 
 /* arch callback */
+int __init __alloc_bootmem_huge_page(struct hstate *h);
 int __init alloc_bootmem_huge_page(struct hstate *h);
 
 void __init hugetlb_bad_size(void);

@@ -2083,7 +2083,9 @@ struct page *alloc_huge_page_noerr(struct vm_area_struct *vma,
 	return page;
 }
 
-int __weak alloc_bootmem_huge_page(struct hstate *h)
+int alloc_bootmem_huge_page(struct hstate *h)
+	__attribute__ ((weak, alias("__alloc_bootmem_huge_page")));
+int __alloc_bootmem_huge_page(struct hstate *h)
 {
 	struct huge_bootmem_page *m;
 	int nr_nodes, node;

@@ -2104,6 +2106,7 @@ int __weak alloc_bootmem_huge_page(struct hstate *h)
 			goto found;
 		}
 	}
+	pr_info("Failed to allocate hugepage of size %ld\n", huge_page_size(h));
 	return 0;
 
 found:

@@ -468,7 +468,7 @@ extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
 			     int psize, int ssize);
 int htab_remove_mapping(unsigned long vstart, unsigned long vend,
 			int psize, int ssize);
-extern void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages);
+extern void pseries_add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages);
 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
 
 #ifdef CONFIG_PPC_PSERIES

@@ -218,18 +218,4 @@ static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr,
 }
 #endif /* CONFIG_HUGETLB_PAGE */
 
-/*
- * FSL Book3E platforms require special gpage handling - the gpages
- * are reserved early in the boot process by memblock instead of via
- * the .dts as on IBM platforms.
- */
-#if defined(CONFIG_HUGETLB_PAGE) && (defined(CONFIG_PPC_FSL_BOOK3E) || \
-    defined(CONFIG_PPC_8xx))
-extern void __init reserve_hugetlb_gpages(void);
-#else
-static inline void reserve_hugetlb_gpages(void)
-{
-}
-#endif
-
 #endif /* _ASM_POWERPC_HUGETLB_H */

@@ -916,13 +916,6 @@ void __init setup_arch(char **cmdline_p)
 	/* Reserve large chunks of memory for use by CMA for KVM. */
 	kvm_cma_reserve();
 
-	/*
-	 * Reserve any gigantic pages requested on the command line.
-	 * memblock needs to have been initialized by the time this is
-	 * called since this will reserve memory.
-	 */
-	reserve_hugetlb_gpages();
-
 	klp_init_thread_info(&init_thread_info);
 
 	init_mm.start_code = (unsigned long)_stext;

@@ -509,7 +509,7 @@ static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
 			phys_addr, block_size, expected_pages);
 	if (phys_addr + (16 * GB) <= memblock_end_of_DRAM()) {
 		memblock_reserve(phys_addr, block_size * expected_pages);
-		add_gpage(phys_addr, block_size, expected_pages);
+		pseries_add_gpage(phys_addr, block_size, expected_pages);
 	}
 	return 0;
 }

@@ -36,26 +36,6 @@
 unsigned int HPAGE_SHIFT;
 EXPORT_SYMBOL(HPAGE_SHIFT);
 
-/*
- * Tracks gpages after the device tree is scanned and before the
- * huge_boot_pages list is ready.  On non-Freescale implementations, this is
- * just used to track 16G pages and so is a single array.  FSL-based
- * implementations may have more than one gpage size, so we need multiple
- * arrays
- */
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-#define MAX_NUMBER_GPAGES	128
-struct psize_gpages {
-	u64 gpage_list[MAX_NUMBER_GPAGES];
-	unsigned int nr_gpages;
-};
-static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT];
-#else
-#define MAX_NUMBER_GPAGES	1024
-static u64 gpage_freearray[MAX_NUMBER_GPAGES];
-static unsigned nr_gpages;
-#endif
-
 #define hugepd_none(hpd)	(hpd_val(hpd) == 0)
 
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz)

@@ -210,145 +190,20 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz
 	return hugepte_offset(*hpdp, addr, pdshift);
 }
 
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-/* Build list of addresses of gigantic pages.  This function is used in early
- * boot before the buddy allocator is setup.
- */
-void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
-{
-	unsigned int idx = shift_to_mmu_psize(__ffs(page_size));
-	int i;
-
-	if (addr == 0)
-		return;
-
-	gpage_freearray[idx].nr_gpages = number_of_pages;
-
-	for (i = 0; i < number_of_pages; i++) {
-		gpage_freearray[idx].gpage_list[i] = addr;
-		addr += page_size;
-	}
-}
-
-/*
- * Moves the gigantic page addresses from the temporary list to the
- * huge_boot_pages list.
- */
-int alloc_bootmem_huge_page(struct hstate *hstate)
-{
-	struct huge_bootmem_page *m;
-	int idx = shift_to_mmu_psize(huge_page_shift(hstate));
-	int nr_gpages = gpage_freearray[idx].nr_gpages;
-
-	if (nr_gpages == 0)
-		return 0;
-
-#ifdef CONFIG_HIGHMEM
-	/*
-	 * If gpages can be in highmem we can't use the trick of storing the
-	 * data structure in the page; allocate space for this
-	 */
-	m = memblock_virt_alloc(sizeof(struct huge_bootmem_page), 0);
-	m->phys = gpage_freearray[idx].gpage_list[--nr_gpages];
-#else
-	m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]);
-#endif
-
-	list_add(&m->list, &huge_boot_pages);
-	gpage_freearray[idx].nr_gpages = nr_gpages;
-	gpage_freearray[idx].gpage_list[nr_gpages] = 0;
-	m->hstate = hstate;
-
-	return 1;
-}
+#ifdef CONFIG_PPC_BOOK3S_64
 /*
- * Scan the command line hugepagesz= options for gigantic pages; store those in
- * a list that we use to allocate the memory once all options are parsed.
+ * Tracks gpages after the device tree is scanned and before the
+ * huge_boot_pages list is ready on pSeries.
  */
-
-unsigned long gpage_npages[MMU_PAGE_COUNT];
-
-static int __init do_gpage_early_setup(char *param, char *val,
-				       const char *unused, void *arg)
-{
-	static phys_addr_t size;
-	unsigned long npages;
-
-	/*
-	 * The hugepagesz and hugepages cmdline options are interleaved.  We
-	 * use the size variable to keep track of whether or not this was done
-	 * properly and skip over instances where it is incorrect.  Other
-	 * command-line parsing code will issue warnings, so we don't need to.
-	 *
-	 */
-	if ((strcmp(param, "default_hugepagesz") == 0) ||
-	    (strcmp(param, "hugepagesz") == 0)) {
-		size = memparse(val, NULL);
-	} else if (strcmp(param, "hugepages") == 0) {
-		if (size != 0) {
-			if (sscanf(val, "%lu", &npages) <= 0)
-				npages = 0;
-			if (npages > MAX_NUMBER_GPAGES) {
-				pr_warn("MMU: %lu pages requested for page "
-#ifdef CONFIG_PHYS_ADDR_T_64BIT
-					"size %llu KB, limiting to "
-#else
-					"size %u KB, limiting to "
-#endif
-					__stringify(MAX_NUMBER_GPAGES) "\n",
-					npages, size / 1024);
-				npages = MAX_NUMBER_GPAGES;
-			}
-			gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages;
-			size = 0;
-		}
-	}
-	return 0;
-}
-
+#define MAX_NUMBER_GPAGES	1024
+__initdata static u64 gpage_freearray[MAX_NUMBER_GPAGES];
+__initdata static unsigned nr_gpages;
 
 /*
- * This function allocates physical space for pages that are larger than the
- * buddy allocator can handle.  We want to allocate these in highmem because
- * the amount of lowmem is limited.  This means that this function MUST be
- * called before lowmem_end_addr is set up in MMU_init() in order for the lmb
- * allocate to grab highmem.
- */
-void __init reserve_hugetlb_gpages(void)
-{
-	static __initdata char cmdline[COMMAND_LINE_SIZE];
-	phys_addr_t size, base;
-	int i;
-
-	strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE);
-	parse_args("hugetlb gpages", cmdline, NULL, 0, 0, 0,
-			NULL, &do_gpage_early_setup);
-
-	/*
-	 * Walk gpage list in reverse, allocating larger page sizes first.
-	 * Skip over unsupported sizes, or sizes that have 0 gpages allocated.
-	 * When we reach the point in the list where pages are no longer
-	 * considered gpages, we're done.
-	 */
-	for (i = MMU_PAGE_COUNT-1; i >= 0; i--) {
-		if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0)
-			continue;
-		else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT))
-			break;
-
-		size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i));
-		base = memblock_alloc_base(size * gpage_npages[i], size,
-					   MEMBLOCK_ALLOC_ANYWHERE);
-		add_gpage(base, size, gpage_npages[i]);
-	}
-}
-
-#else /* !PPC_FSL_BOOK3E */
-
-/* Build list of addresses of gigantic pages.  This function is used in early
+ * Build list of addresses of gigantic pages.  This function is used in early
  * boot before the buddy allocator is setup.
  */
-void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
+void __init pseries_add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
 {
 	if (!addr)
 		return;

@@ -360,10 +215,7 @@ void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
 	}
 }
 
-/* Moves the gigantic page addresses from the temporary list to the
- * huge_boot_pages list.
- */
-int alloc_bootmem_huge_page(struct hstate *hstate)
+int __init pseries_alloc_bootmem_huge_page(struct hstate *hstate)
 {
 	struct huge_bootmem_page *m;
 	if (nr_gpages == 0)

@@ -376,6 +228,17 @@ int alloc_bootmem_huge_page(struct hstate *hstate)
 }
 #endif
 
+
+int __init alloc_bootmem_huge_page(struct hstate *h)
+{
+
+#ifdef CONFIG_PPC_BOOK3S_64
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return pseries_alloc_bootmem_huge_page(h);
+#endif
+	return __alloc_bootmem_huge_page(h);
+}
+
 #if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
 #define HUGEPD_FREELIST_SIZE \
 	((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))

@@ -132,8 +132,6 @@ void __init MMU_init(void)
 	 * Reserve gigantic pages for hugetlb.  This MUST occur before
 	 * lowmem_end_addr is initialized below.
 	 */
-	reserve_hugetlb_gpages();
-
 	if (memblock.memory.cnt > 1) {
 #ifndef CONFIG_WII
 		memblock_enforce_memory_limit(memblock.memory.regions[0].size);

@@ -54,9 +54,7 @@ static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static inline bool gigantic_page_supported(void)
 {
-	if (radix_enabled())
-		return true;
-	return false;
+	return true;
 }
 #endif