Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 260 insertions, 0 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
new file mode 100644
index 000000000000..4eb5ae3fbe10
--- /dev/null
+++ b/mm/hugetlb.c
@@ -0,0 +1,260 @@
+/*
+ * Generic hugetlb support.
+ * (C) William Irwin, April 2004
+ */
+#include <linux/gfp.h>
+#include <linux/list.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/sysctl.h>
+#include <linux/highmem.h>
+#include <linux/nodemask.h>
+
+const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
+static unsigned long nr_huge_pages, free_huge_pages;
+unsigned long max_huge_pages;
+static struct list_head hugepage_freelists[MAX_NUMNODES];
+static unsigned int nr_huge_pages_node[MAX_NUMNODES];
+static unsigned int free_huge_pages_node[MAX_NUMNODES];
+static DEFINE_SPINLOCK(hugetlb_lock);
+
+static void enqueue_huge_page(struct page *page)
+{
+        int nid = page_to_nid(page);
+        list_add(&page->lru, &hugepage_freelists[nid]);
+        free_huge_pages++;
+        free_huge_pages_node[nid]++;
+}
+
+static struct page *dequeue_huge_page(void)
+{
+        int nid = numa_node_id();
+        struct page *page = NULL;
+
+        if (list_empty(&hugepage_freelists[nid])) {
+                for (nid = 0; nid < MAX_NUMNODES; ++nid)
+                        if (!list_empty(&hugepage_freelists[nid]))
+                                break;
+        }
+        if (nid >= 0 && nid < MAX_NUMNODES &&
+            !list_empty(&hugepage_freelists[nid])) {
+                page = list_entry(hugepage_freelists[nid].next,
+                                  struct page, lru);
+                list_del(&page->lru);
+                free_huge_pages--;
+                free_huge_pages_node[nid]--;
+        }
+        return page;
+}
+
+static struct page *alloc_fresh_huge_page(void)
+{
+        static int nid = 0;
+        struct page *page;
+        page = alloc_pages_node(nid, GFP_HIGHUSER|__GFP_COMP|__GFP_NOWARN,
+                                        HUGETLB_PAGE_ORDER);
+        nid = (nid + 1) % num_online_nodes();
+        if (page) {
+                nr_huge_pages++;
+                nr_huge_pages_node[page_to_nid(page)]++;
+        }
+        return page;
+}
+
+void free_huge_page(struct page *page)
+{
+        BUG_ON(page_count(page));
+
+        INIT_LIST_HEAD(&page->lru);
+        page[1].mapping = NULL;
+
+        spin_lock(&hugetlb_lock);
+        enqueue_huge_page(page);
+        spin_unlock(&hugetlb_lock);
+}
+
+struct page *alloc_huge_page(void)
+{
+        struct page *page;
+        int i;
+
+        spin_lock(&hugetlb_lock);
+        page = dequeue_huge_page();
+        if (!page) {
+                spin_unlock(&hugetlb_lock);
+                return NULL;
+        }
+        spin_unlock(&hugetlb_lock);
+        set_page_count(page, 1);
+        page[1].mapping = (void *)free_huge_page;
+        for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); ++i)
+                clear_highpage(&page[i]);
+        return page;
+}
+
+static int __init hugetlb_init(void)
+{
+        unsigned long i;
+        struct page *page;
+
+        for (i = 0; i < MAX_NUMNODES; ++i)
+                INIT_LIST_HEAD(&hugepage_freelists[i]);
+
+        for (i = 0; i < max_huge_pages; ++i) {
+                page = alloc_fresh_huge_page();
+                if (!page)
+                        break;
+                spin_lock(&hugetlb_lock);
+                enqueue_huge_page(page);
+                spin_unlock(&hugetlb_lock);
+        }
+        max_huge_pages = free_huge_pages = nr_huge_pages = i;
+        printk("Total HugeTLB memory allocated, %ld\n", free_huge_pages);
+        return 0;
+}
+module_init(hugetlb_init);
+
+static int __init hugetlb_setup(char *s)
+{
+        if (sscanf(s, "%lu", &max_huge_pages) <= 0)
+                max_huge_pages = 0;
+        return 1;
+}
+__setup("hugepages=", hugetlb_setup);
+
+#ifdef CONFIG_SYSCTL
+static void update_and_free_page(struct page *page)
+{
+        int i;
+        nr_huge_pages--;
+        nr_huge_pages_node[page_zone(page)->zone_pgdat->node_id]--;
+        for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++) {
+                page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced |
+                                1 << PG_dirty | 1 << PG_active | 1 << PG_reserved |
+                                1 << PG_private | 1<< PG_writeback);
+                set_page_count(&page[i], 0);
+        }
+        set_page_count(page, 1);
+        __free_pages(page, HUGETLB_PAGE_ORDER);
+}
+
+#ifdef CONFIG_HIGHMEM
+static void try_to_free_low(unsigned long count)
+{
+        int i, nid;
+        for (i = 0; i < MAX_NUMNODES; ++i) {
+                struct page *page, *next;
+                list_for_each_entry_safe(page, next, &hugepage_freelists[i], lru) {
+                        if (PageHighMem(page))
+                                continue;
+                        list_del(&page->lru);
+                        update_and_free_page(page);
+                        nid = page_zone(page)->zone_pgdat->node_id;
+                        free_huge_pages--;
+                        free_huge_pages_node[nid]--;
+                        if (count >= nr_huge_pages)
+                                return;
+                }
+        }
+}
+#else
+static inline void try_to_free_low(unsigned long count)
+{
+}
+#endif
+
+static unsigned long set_max_huge_pages(unsigned long count)
+{
+        while (count > nr_huge_pages) {
+                struct page *page = alloc_fresh_huge_page();
+                if (!page)
+                        return nr_huge_pages;
+                spin_lock(&hugetlb_lock);
+                enqueue_huge_page(page);
+                spin_unlock(&hugetlb_lock);
+        }
+        if (count >= nr_huge_pages)
+                return nr_huge_pages;
+
+        spin_lock(&hugetlb_lock);
+        try_to_free_low(count);
+        while (count < nr_huge_pages) {
+                struct page *page = dequeue_huge_page();
+                if (!page)
+                        break;
+                update_and_free_page(page);
+        }
+        spin_unlock(&hugetlb_lock);
+        return nr_huge_pages;
+}
+
+int hugetlb_sysctl_handler(struct ctl_table *table, int write,
+                           struct file *file, void __user *buffer,
+                           size_t *length, loff_t *ppos)
+{
+        proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
+        max_huge_pages = set_max_huge_pages(max_huge_pages);
+        return 0;
+}
+#endif /* CONFIG_SYSCTL */
+
+int hugetlb_report_meminfo(char *buf)
+{
+        return sprintf(buf,
+                        "HugePages_Total: %5lu\n"
+                        "HugePages_Free:  %5lu\n"
+                        "Hugepagesize:    %5lu kB\n",
+                        nr_huge_pages,
+                        free_huge_pages,
+                        HPAGE_SIZE/1024);
+}
+
+int hugetlb_report_node_meminfo(int nid, char *buf)
+{
+        return sprintf(buf,
+                "Node %d HugePages_Total: %5u\n"
+                "Node %d HugePages_Free:  %5u\n",
+                nid, nr_huge_pages_node[nid],
+                nid, free_huge_pages_node[nid]);
+}
+
+int is_hugepage_mem_enough(size_t size)
+{
+        return (size + ~HPAGE_MASK)/HPAGE_SIZE <= free_huge_pages;
+}
+
+/* Return the number pages of memory we physically have, in PAGE_SIZE units. */
+unsigned long hugetlb_total_pages(void)
+{
+        return nr_huge_pages * (HPAGE_SIZE / PAGE_SIZE);
+}
+EXPORT_SYMBOL(hugetlb_total_pages);
+
+/*
+ * We cannot handle pagefaults against hugetlb pages at all.  They cause
+ * handle_mm_fault() to try to instantiate regular-sized pages in the
+ * hugegpage VMA.  do_page_fault() is supposed to trap this, so BUG is we get
+ * this far.
+ */
+static struct page *hugetlb_nopage(struct vm_area_struct *vma,
+                                unsigned long address, int *unused)
+{
+        BUG();
+        return NULL;
+}
+
+struct vm_operations_struct hugetlb_vm_ops = {
+        .nopage = hugetlb_nopage,
+};
+
+void zap_hugepage_range(struct vm_area_struct *vma,
+                        unsigned long start, unsigned long length)
+{
+        struct mm_struct *mm = vma->vm_mm;
+
+        spin_lock(&mm->page_table_lock);
+        unmap_hugepage_range(vma, start, start + length);
+        spin_unlock(&mm->page_table_lock);
+}