Linux-2.6.12-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!
diff --git a/mm/bootmem.c b/mm/bootmem.c
new file mode 100644
index 0000000..260e703
--- /dev/null
+++ b/mm/bootmem.c
@@ -0,0 +1,400 @@
+/*
+ * linux/mm/bootmem.c
+ *
+ * Copyright (C) 1999 Ingo Molnar
+ * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
+ *
+ * simple boot-time physical memory area allocator and
+ * free memory collector. It's used to deal with reserved
+ * system memory and memory holes as well.
+ */
+
+#include <linux/mm.h>
+#include <linux/kernel_stat.h>
+#include <linux/swap.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+#include "internal.h"
+
+/*
+ * Access to this subsystem has to be serialized externally. (this is
+ * true for the boot process anyway)
+ */
+unsigned long max_low_pfn;
+unsigned long min_low_pfn;
+unsigned long max_pfn;
+
+EXPORT_SYMBOL(max_pfn); /* This is exported so
+ * dma_get_required_mask(), which uses
+ * it, can be an inline function */
+
+/* return the number of _pages_ that will be allocated for the boot bitmap */
+unsigned long __init bootmem_bootmap_pages (unsigned long pages)
+{
+ unsigned long mapsize;
+
+ mapsize = (pages+7)/8;
+ mapsize = (mapsize + ~PAGE_MASK) & PAGE_MASK;
+ mapsize >>= PAGE_SHIFT;
+
+ return mapsize;
+}
+
+/*
+ * Called once to set up the allocator itself.
+ */
+static unsigned long __init init_bootmem_core (pg_data_t *pgdat,
+ unsigned long mapstart, unsigned long start, unsigned long end)
+{
+ bootmem_data_t *bdata = pgdat->bdata;
+ unsigned long mapsize = ((end - start)+7)/8;
+
+ pgdat->pgdat_next = pgdat_list;
+ pgdat_list = pgdat;
+
+ mapsize = (mapsize + (sizeof(long) - 1UL)) & ~(sizeof(long) - 1UL);
+ bdata->node_bootmem_map = phys_to_virt(mapstart << PAGE_SHIFT);
+ bdata->node_boot_start = (start << PAGE_SHIFT);
+ bdata->node_low_pfn = end;
+
+ /*
+ * Initially all pages are reserved - setup_arch() has to
+ * register free RAM areas explicitly.
+ */
+ memset(bdata->node_bootmem_map, 0xff, mapsize);
+
+ return mapsize;
+}
+
+/*
+ * Marks a particular physical memory range as unallocatable. Usable RAM
+ * might be used for boot-time allocations - or it might get added
+ * to the free page pool later on.
+ */
+static void __init reserve_bootmem_core(bootmem_data_t *bdata, unsigned long addr, unsigned long size)
+{
+ unsigned long i;
+ /*
+ * round up, partially reserved pages are considered
+ * fully reserved.
+ */
+ unsigned long sidx = (addr - bdata->node_boot_start)/PAGE_SIZE;
+ unsigned long eidx = (addr + size - bdata->node_boot_start +
+ PAGE_SIZE-1)/PAGE_SIZE;
+ unsigned long end = (addr + size + PAGE_SIZE-1)/PAGE_SIZE;
+
+ BUG_ON(!size);
+ BUG_ON(sidx >= eidx);
+ BUG_ON((addr >> PAGE_SHIFT) >= bdata->node_low_pfn);
+ BUG_ON(end > bdata->node_low_pfn);
+
+ for (i = sidx; i < eidx; i++)
+ if (test_and_set_bit(i, bdata->node_bootmem_map)) {
+#ifdef CONFIG_DEBUG_BOOTMEM
+ printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);
+#endif
+ }
+}
+
+static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr, unsigned long size)
+{
+ unsigned long i;
+ unsigned long start;
+ /*
+ * round down end of usable mem, partially free pages are
+ * considered reserved.
+ */
+ unsigned long sidx;
+ unsigned long eidx = (addr + size - bdata->node_boot_start)/PAGE_SIZE;
+ unsigned long end = (addr + size)/PAGE_SIZE;
+
+ BUG_ON(!size);
+ BUG_ON(end > bdata->node_low_pfn);
+
+ if (addr < bdata->last_success)
+ bdata->last_success = addr;
+
+ /*
+ * Round up the beginning of the address.
+ */
+ start = (addr + PAGE_SIZE-1) / PAGE_SIZE;
+ sidx = start - (bdata->node_boot_start/PAGE_SIZE);
+
+ for (i = sidx; i < eidx; i++) {
+ if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
+ BUG();
+ }
+}
+
+/*
+ * We 'merge' subsequent allocations to save space. We might 'lose'
+ * some fraction of a page if allocations cannot be satisfied due to
+ * size constraints on boxes where there is physical RAM space
+ * fragmentation - in these cases (mostly large memory boxes) this
+ * is not a problem.
+ *
+ * On low memory boxes we get it right in 100% of the cases.
+ *
+ * alignment has to be a power of 2 value.
+ *
+ * NOTE: This function is _not_ reentrant.
+ */
+static void * __init
+__alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
+ unsigned long align, unsigned long goal)
+{
+ unsigned long offset, remaining_size, areasize, preferred;
+ unsigned long i, start = 0, incr, eidx;
+ void *ret;
+
+ if(!size) {
+ printk("__alloc_bootmem_core(): zero-sized request\n");
+ BUG();
+ }
+ BUG_ON(align & (align-1));
+
+ eidx = bdata->node_low_pfn - (bdata->node_boot_start >> PAGE_SHIFT);
+ offset = 0;
+ if (align &&
+ (bdata->node_boot_start & (align - 1UL)) != 0)
+ offset = (align - (bdata->node_boot_start & (align - 1UL)));
+ offset >>= PAGE_SHIFT;
+
+ /*
+ * We try to allocate bootmem pages above 'goal'
+ * first, then we try to allocate lower pages.
+ */
+ if (goal && (goal >= bdata->node_boot_start) &&
+ ((goal >> PAGE_SHIFT) < bdata->node_low_pfn)) {
+ preferred = goal - bdata->node_boot_start;
+
+ if (bdata->last_success >= preferred)
+ preferred = bdata->last_success;
+ } else
+ preferred = 0;
+
+ preferred = ((preferred + align - 1) & ~(align - 1)) >> PAGE_SHIFT;
+ preferred += offset;
+ areasize = (size+PAGE_SIZE-1)/PAGE_SIZE;
+ incr = align >> PAGE_SHIFT ? : 1;
+
+restart_scan:
+ for (i = preferred; i < eidx; i += incr) {
+ unsigned long j;
+ i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i);
+ i = ALIGN(i, incr);
+ if (test_bit(i, bdata->node_bootmem_map))
+ continue;
+ for (j = i + 1; j < i + areasize; ++j) {
+ if (j >= eidx)
+ goto fail_block;
+ if (test_bit (j, bdata->node_bootmem_map))
+ goto fail_block;
+ }
+ start = i;
+ goto found;
+ fail_block:
+ i = ALIGN(j, incr);
+ }
+
+ if (preferred > offset) {
+ preferred = offset;
+ goto restart_scan;
+ }
+ return NULL;
+
+found:
+ bdata->last_success = start << PAGE_SHIFT;
+ BUG_ON(start >= eidx);
+
+ /*
+ * Is the next page of the previous allocation-end the start
+ * of this allocation's buffer? If yes then we can 'merge'
+ * the previous partial page with this allocation.
+ */
+ if (align < PAGE_SIZE &&
+ bdata->last_offset && bdata->last_pos+1 == start) {
+ offset = (bdata->last_offset+align-1) & ~(align-1);
+ BUG_ON(offset > PAGE_SIZE);
+ remaining_size = PAGE_SIZE-offset;
+ if (size < remaining_size) {
+ areasize = 0;
+ /* last_pos unchanged */
+ bdata->last_offset = offset+size;
+ ret = phys_to_virt(bdata->last_pos*PAGE_SIZE + offset +
+ bdata->node_boot_start);
+ } else {
+ remaining_size = size - remaining_size;
+ areasize = (remaining_size+PAGE_SIZE-1)/PAGE_SIZE;
+ ret = phys_to_virt(bdata->last_pos*PAGE_SIZE + offset +
+ bdata->node_boot_start);
+ bdata->last_pos = start+areasize-1;
+ bdata->last_offset = remaining_size;
+ }
+ bdata->last_offset &= ~PAGE_MASK;
+ } else {
+ bdata->last_pos = start + areasize - 1;
+ bdata->last_offset = size & ~PAGE_MASK;
+ ret = phys_to_virt(start * PAGE_SIZE + bdata->node_boot_start);
+ }
+
+ /*
+ * Reserve the area now:
+ */
+ for (i = start; i < start+areasize; i++)
+ if (unlikely(test_and_set_bit(i, bdata->node_bootmem_map)))
+ BUG();
+ memset(ret, 0, size);
+ return ret;
+}
+
+static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat)
+{
+ struct page *page;
+ bootmem_data_t *bdata = pgdat->bdata;
+ unsigned long i, count, total = 0;
+ unsigned long idx;
+ unsigned long *map;
+ int gofast = 0;
+
+ BUG_ON(!bdata->node_bootmem_map);
+
+ count = 0;
+ /* first extant page of the node */
+ page = virt_to_page(phys_to_virt(bdata->node_boot_start));
+ idx = bdata->node_low_pfn - (bdata->node_boot_start >> PAGE_SHIFT);
+ map = bdata->node_bootmem_map;
+ /* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */
+ if (bdata->node_boot_start == 0 ||
+ ffs(bdata->node_boot_start) - PAGE_SHIFT > ffs(BITS_PER_LONG))
+ gofast = 1;
+ for (i = 0; i < idx; ) {
+ unsigned long v = ~map[i / BITS_PER_LONG];
+ if (gofast && v == ~0UL) {
+ int j, order;
+
+ count += BITS_PER_LONG;
+ __ClearPageReserved(page);
+ order = ffs(BITS_PER_LONG) - 1;
+ set_page_refs(page, order);
+ for (j = 1; j < BITS_PER_LONG; j++) {
+ if (j + 16 < BITS_PER_LONG)
+ prefetchw(page + j + 16);
+ __ClearPageReserved(page + j);
+ }
+ __free_pages(page, order);
+ i += BITS_PER_LONG;
+ page += BITS_PER_LONG;
+ } else if (v) {
+ unsigned long m;
+ for (m = 1; m && i < idx; m<<=1, page++, i++) {
+ if (v & m) {
+ count++;
+ __ClearPageReserved(page);
+ set_page_refs(page, 0);
+ __free_page(page);
+ }
+ }
+ } else {
+ i+=BITS_PER_LONG;
+ page += BITS_PER_LONG;
+ }
+ }
+ total += count;
+
+ /*
+ * Now free the allocator bitmap itself, it's not
+ * needed anymore:
+ */
+ page = virt_to_page(bdata->node_bootmem_map);
+ count = 0;
+ for (i = 0; i < ((bdata->node_low_pfn-(bdata->node_boot_start >> PAGE_SHIFT))/8 + PAGE_SIZE-1)/PAGE_SIZE; i++,page++) {
+ count++;
+ __ClearPageReserved(page);
+ set_page_count(page, 1);
+ __free_page(page);
+ }
+ total += count;
+ bdata->node_bootmem_map = NULL;
+
+ return total;
+}
+
+unsigned long __init init_bootmem_node (pg_data_t *pgdat, unsigned long freepfn, unsigned long startpfn, unsigned long endpfn)
+{
+ return(init_bootmem_core(pgdat, freepfn, startpfn, endpfn));
+}
+
+void __init reserve_bootmem_node (pg_data_t *pgdat, unsigned long physaddr, unsigned long size)
+{
+ reserve_bootmem_core(pgdat->bdata, physaddr, size);
+}
+
+void __init free_bootmem_node (pg_data_t *pgdat, unsigned long physaddr, unsigned long size)
+{
+ free_bootmem_core(pgdat->bdata, physaddr, size);
+}
+
+unsigned long __init free_all_bootmem_node (pg_data_t *pgdat)
+{
+ return(free_all_bootmem_core(pgdat));
+}
+
+unsigned long __init init_bootmem (unsigned long start, unsigned long pages)
+{
+ max_low_pfn = pages;
+ min_low_pfn = start;
+ return(init_bootmem_core(NODE_DATA(0), start, 0, pages));
+}
+
+#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
+void __init reserve_bootmem (unsigned long addr, unsigned long size)
+{
+ reserve_bootmem_core(NODE_DATA(0)->bdata, addr, size);
+}
+#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
+
+void __init free_bootmem (unsigned long addr, unsigned long size)
+{
+ free_bootmem_core(NODE_DATA(0)->bdata, addr, size);
+}
+
+unsigned long __init free_all_bootmem (void)
+{
+ return(free_all_bootmem_core(NODE_DATA(0)));
+}
+
+void * __init __alloc_bootmem (unsigned long size, unsigned long align, unsigned long goal)
+{
+ pg_data_t *pgdat = pgdat_list;
+ void *ptr;
+
+ for_each_pgdat(pgdat)
+ if ((ptr = __alloc_bootmem_core(pgdat->bdata, size,
+ align, goal)))
+ return(ptr);
+
+ /*
+ * Whoops, we cannot satisfy the allocation request.
+ */
+ printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
+ panic("Out of memory");
+ return NULL;
+}
+
+void * __init __alloc_bootmem_node (pg_data_t *pgdat, unsigned long size, unsigned long align, unsigned long goal)
+{
+ void *ptr;
+
+ ptr = __alloc_bootmem_core(pgdat->bdata, size, align, goal);
+ if (ptr)
+ return (ptr);
+
+ return __alloc_bootmem(size, align, goal);
+}
+