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authorMaksym Planeta <mcsim.planeta@gmail.com>2012-04-08 09:21:52 +0300
committerSamuel Thibault <samuel.thibault@ens-lyon.org>2012-04-08 22:22:00 +0200
commitd43f1c20f6608ab5a6352a181308309c33b81c5b (patch)
treebb712f32e537229e75705cd2f20255b173e72348 /mach-defpager
parent907cbb6676831d950575d097cb4bef3fc5f7d00d (diff)
Allocate pager's map on demand.
* mach-defpager/default_pager.c (pager_get_direct_map): New function. (pager_alloc): Initialize map field to NULL. (pager_allocated, pager_pages, pager_extend, pager_write_offset): Use pager_get_direct_map to access to pager's map.
Diffstat (limited to 'mach-defpager')
-rw-r--r--mach-defpager/default_pager.c76
1 files changed, 46 insertions, 30 deletions
diff --git a/mach-defpager/default_pager.c b/mach-defpager/default_pager.c
index 9935e45d..b467cbce 100644
--- a/mach-defpager/default_pager.c
+++ b/mach-defpager/default_pager.c
@@ -703,6 +703,43 @@ typedef struct dpager *dpager_t;
vm_size_t max_doubled_size = 4 * 1024 * 1024; /* 4 meg */
/*
+ * Return first level map for pager.
+ * If there is no such map, than allocate it.
+ */
+dp_map_t pager_get_direct_map(pager)
+ register dpager_t pager;
+{
+ register dp_map_t mapptr, emapptr;
+ register vm_size_t size = pager->size;
+
+ if (pager->map)
+ return pager->map;
+ /*
+ * Allocate and initialize the block map
+ */
+ {
+ register vm_size_t alloc_size;
+ dp_map_t init_value;
+
+ if (INDIRECT_PAGEMAP(size)) {
+ alloc_size = INDIRECT_PAGEMAP_SIZE(size);
+ init_value = (dp_map_t)0;
+ } else {
+ alloc_size = PAGEMAP_SIZE(size);
+ init_value = (dp_map_t)NO_BLOCK;
+ }
+
+ mapptr = (dp_map_t) kalloc(alloc_size);
+ for (emapptr = &mapptr[(alloc_size-1) / sizeof(vm_offset_t)];
+ emapptr >= mapptr;
+ emapptr--)
+ emapptr->indirect = init_value;
+ }
+ pager->map = mapptr;
+ return mapptr;
+}
+
+/*
* Attach a new paging object to a paging partition
*/
void
@@ -734,29 +771,7 @@ pager_alloc(pager, part, size)
} else
size = ROUNDUP_TO_PAGEMAP(size);
- /*
- * Allocate and initialize the block map
- */
- {
- register vm_size_t alloc_size;
- dp_map_t init_value;
-
- if (INDIRECT_PAGEMAP(size)) {
- alloc_size = INDIRECT_PAGEMAP_SIZE(size);
- init_value = (dp_map_t)0;
- } else {
- alloc_size = PAGEMAP_SIZE(size);
- init_value = (dp_map_t)NO_BLOCK;
- }
-
- mapptr = (dp_map_t) kalloc(alloc_size);
- for (emapptr = &mapptr[(alloc_size-1) / sizeof(vm_offset_t)];
- emapptr >= mapptr;
- emapptr--)
- emapptr->indirect = init_value;
-
- }
- pager->map = mapptr;
+ pager->map = NULL;
pager->size = size;
pager->limit = (vm_size_t)-1;
@@ -790,7 +805,7 @@ pager_allocated(pager)
size = pager->size; /* in pages */
asize = 0; /* allocated, in pages */
- map = pager->map;
+ map = pager_get_direct_map(pager);
if (INDIRECT_PAGEMAP(size)) {
for (emap = &map[INDIRECT_PAGEMAP_ENTRIES(size)];
@@ -834,7 +849,7 @@ pager_pages(pager, pages, numpages)
vm_offset_t offset;
size = pager->size; /* in pages */
- map = pager->map;
+ map = pager_get_direct_map(pager);
actual = 0;
offset = 0;
@@ -911,7 +926,7 @@ pager_extend(pager, new_size)
*/
new_mapptr = (dp_map_t)
kalloc(INDIRECT_PAGEMAP_SIZE(new_size));
- old_mapptr = pager->map;
+ old_mapptr = pager_get_direct_map(pager);
for (i = 0; i < INDIRECT_PAGEMAP_ENTRIES(old_size); i++)
new_mapptr[i] = old_mapptr[i];
for (; i < INDIRECT_PAGEMAP_ENTRIES(new_size); i++)
@@ -956,7 +971,7 @@ pager_extend(pager, new_size)
* Allocate new second-level map first.
*/
new_mapptr = (dp_map_t) kalloc(PAGEMAP_SIZE(PAGEMAP_ENTRIES));
- old_mapptr = pager->map;
+ old_mapptr = pager_get_direct_map(pager);
for (i = 0; i < old_size; i++)
new_mapptr[i] = old_mapptr[i];
for (; i < PAGEMAP_ENTRIES; i++)
@@ -1015,7 +1030,7 @@ pager_extend(pager, new_size)
* Enlarging a direct block.
*/
new_mapptr = (dp_map_t) kalloc(PAGEMAP_SIZE(new_size));
- old_mapptr = pager->map;
+ old_mapptr = pager_get_direct_map(pager);
for (i = 0; i < old_size; i++)
new_mapptr[i] = old_mapptr[i];
for (; i < new_size; i++)
@@ -1464,7 +1479,8 @@ pager_write_offset(pager, offset)
if (INDIRECT_PAGEMAP(pager->size)) {
ddprintf ("pager_write_offset: indirect\n");
- mapptr = pager->map[f_page/PAGEMAP_ENTRIES].indirect;
+ mapptr = pager_get_direct_map(pager);
+ mapptr = mapptr[f_page/PAGEMAP_ENTRIES].indirect;
if (mapptr == 0) {
/*
* Allocate the indirect block
@@ -1503,7 +1519,7 @@ pager_write_offset(pager, offset)
f_page %= PAGEMAP_ENTRIES;
}
else {
- mapptr = pager->map;
+ mapptr = pager_get_direct_map(pager);
}
block = mapptr[f_page];