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authorRussell King <rmk+kernel@arm.linux.org.uk>2010-05-17 17:24:04 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-05-17 17:24:04 +0100
commitac1d426e825ab5778995f2f6f053ca2e6b45c622 (patch)
tree75b91356ca39463e0112931aa6790802fb1e07a2 /mm/rmap.c
parentfda0e18c8a7a3e02747c2b045b4fcd2c920410b9 (diff)
parenta3685f00652af83f12b63e3b4ef48f29581ba48b (diff)
Merge branch 'devel-stable' into devel
Conflicts: arch/arm/Kconfig arch/arm/include/asm/system.h arch/arm/mm/Kconfig
Diffstat (limited to 'mm/rmap.c')
-rw-r--r--mm/rmap.c34
1 files changed, 26 insertions, 8 deletions
diff --git a/mm/rmap.c b/mm/rmap.c
index fcd593c9c99..07fc9475879 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -133,8 +133,8 @@ int anon_vma_prepare(struct vm_area_struct *vma)
goto out_enomem_free_avc;
allocated = anon_vma;
}
- spin_lock(&anon_vma->lock);
+ spin_lock(&anon_vma->lock);
/* page_table_lock to protect against threads */
spin_lock(&mm->page_table_lock);
if (likely(!vma->anon_vma)) {
@@ -144,14 +144,15 @@ int anon_vma_prepare(struct vm_area_struct *vma)
list_add(&avc->same_vma, &vma->anon_vma_chain);
list_add(&avc->same_anon_vma, &anon_vma->head);
allocated = NULL;
+ avc = NULL;
}
spin_unlock(&mm->page_table_lock);
-
spin_unlock(&anon_vma->lock);
- if (unlikely(allocated)) {
+
+ if (unlikely(allocated))
anon_vma_free(allocated);
+ if (unlikely(avc))
anon_vma_chain_free(avc);
- }
}
return 0;
@@ -182,7 +183,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
{
struct anon_vma_chain *avc, *pavc;
- list_for_each_entry(pavc, &src->anon_vma_chain, same_vma) {
+ list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
avc = anon_vma_chain_alloc();
if (!avc)
goto enomem_failure;
@@ -232,6 +233,7 @@ int anon_vma_fork(struct vm_area_struct *vma, struct vm_area_struct *pvma)
out_error_free_anon_vma:
anon_vma_free(anon_vma);
out_error:
+ unlink_anon_vmas(vma);
return -ENOMEM;
}
@@ -729,13 +731,29 @@ void page_move_anon_rmap(struct page *page,
* @page: the page to add the mapping to
* @vma: the vm area in which the mapping is added
* @address: the user virtual address mapped
+ * @exclusive: the page is exclusively owned by the current process
*/
static void __page_set_anon_rmap(struct page *page,
- struct vm_area_struct *vma, unsigned long address)
+ struct vm_area_struct *vma, unsigned long address, int exclusive)
{
struct anon_vma *anon_vma = vma->anon_vma;
BUG_ON(!anon_vma);
+
+ /*
+ * If the page isn't exclusively mapped into this vma,
+ * we must use the _oldest_ possible anon_vma for the
+ * page mapping!
+ *
+ * So take the last AVC chain entry in the vma, which is
+ * the deepest ancestor, and use the anon_vma from that.
+ */
+ if (!exclusive) {
+ struct anon_vma_chain *avc;
+ avc = list_entry(vma->anon_vma_chain.prev, struct anon_vma_chain, same_vma);
+ anon_vma = avc->anon_vma;
+ }
+
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON;
page->mapping = (struct address_space *) anon_vma;
page->index = linear_page_index(vma, address);
@@ -790,7 +808,7 @@ void page_add_anon_rmap(struct page *page,
VM_BUG_ON(!PageLocked(page));
VM_BUG_ON(address < vma->vm_start || address >= vma->vm_end);
if (first)
- __page_set_anon_rmap(page, vma, address);
+ __page_set_anon_rmap(page, vma, address, 0);
else
__page_check_anon_rmap(page, vma, address);
}
@@ -812,7 +830,7 @@ void page_add_new_anon_rmap(struct page *page,
SetPageSwapBacked(page);
atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */
__inc_zone_page_state(page, NR_ANON_PAGES);
- __page_set_anon_rmap(page, vma, address);
+ __page_set_anon_rmap(page, vma, address, 1);
if (page_evictable(page, vma))
lru_cache_add_lru(page, LRU_ACTIVE_ANON);
else