aboutsummaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
Diffstat (limited to 'mm')
-rw-r--r--mm/hugetlb.c11
-rw-r--r--mm/memory.c48
-rw-r--r--mm/mempolicy.c2
-rw-r--r--mm/mmap.c6
-rw-r--r--mm/mremap.c2
-rw-r--r--mm/nommu.c6
-rw-r--r--mm/page_alloc.c21
7 files changed, 61 insertions, 35 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index fbd1111ea11..6bf720bc662 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -301,6 +301,7 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
{
struct mm_struct *mm = vma->vm_mm;
unsigned long address;
+ pte_t *ptep;
pte_t pte;
struct page *page;
@@ -309,9 +310,17 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
BUG_ON(end & ~HPAGE_MASK);
for (address = start; address < end; address += HPAGE_SIZE) {
- pte = huge_ptep_get_and_clear(mm, address, huge_pte_offset(mm, address));
+ ptep = huge_pte_offset(mm, address);
+ if (! ptep)
+ /* This can happen on truncate, or if an
+ * mmap() is aborted due to an error before
+ * the prefault */
+ continue;
+
+ pte = huge_ptep_get_and_clear(mm, address, ptep);
if (pte_none(pte))
continue;
+
page = pte_page(pte);
put_page(page);
}
diff --git a/mm/memory.c b/mm/memory.c
index 6fe77acbc1c..e046b7e4b53 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -913,9 +913,13 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
pud = pud_offset(pgd, pg);
BUG_ON(pud_none(*pud));
pmd = pmd_offset(pud, pg);
- BUG_ON(pmd_none(*pmd));
+ if (pmd_none(*pmd))
+ return i ? : -EFAULT;
pte = pte_offset_map(pmd, pg);
- BUG_ON(pte_none(*pte));
+ if (pte_none(*pte)) {
+ pte_unmap(pte);
+ return i ? : -EFAULT;
+ }
if (pages) {
pages[i] = pte_page(*pte);
get_page(pages[i]);
@@ -940,11 +944,13 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
}
spin_lock(&mm->page_table_lock);
do {
+ int write_access = write;
struct page *page;
- int lookup_write = write;
cond_resched_lock(&mm->page_table_lock);
- while (!(page = follow_page(mm, start, lookup_write))) {
+ while (!(page = follow_page(mm, start, write_access))) {
+ int ret;
+
/*
* Shortcut for anonymous pages. We don't want
* to force the creation of pages tables for
@@ -952,13 +958,23 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
* nobody touched so far. This is important
* for doing a core dump for these mappings.
*/
- if (!lookup_write &&
- untouched_anonymous_page(mm,vma,start)) {
+ if (!write && untouched_anonymous_page(mm,vma,start)) {
page = ZERO_PAGE(start);
break;
}
spin_unlock(&mm->page_table_lock);
- switch (handle_mm_fault(mm,vma,start,write)) {
+ ret = __handle_mm_fault(mm, vma, start, write_access);
+
+ /*
+ * The VM_FAULT_WRITE bit tells us that do_wp_page has
+ * broken COW when necessary, even if maybe_mkwrite
+ * decided not to set pte_write. We can thus safely do
+ * subsequent page lookups as if they were reads.
+ */
+ if (ret & VM_FAULT_WRITE)
+ write_access = 0;
+
+ switch (ret & ~VM_FAULT_WRITE) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
@@ -972,14 +988,6 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
default:
BUG();
}
- /*
- * Now that we have performed a write fault
- * and surely no longer have a shared page we
- * shouldn't write, we shouldn't ignore an
- * unwritable page in the page table if
- * we are forcing write access.
- */
- lookup_write = write && !force;
spin_lock(&mm->page_table_lock);
}
if (pages) {
@@ -1229,6 +1237,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct * vma,
struct page *old_page, *new_page;
unsigned long pfn = pte_pfn(pte);
pte_t entry;
+ int ret;
if (unlikely(!pfn_valid(pfn))) {
/*
@@ -1256,7 +1265,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct * vma,
lazy_mmu_prot_update(entry);
pte_unmap(page_table);
spin_unlock(&mm->page_table_lock);
- return VM_FAULT_MINOR;
+ return VM_FAULT_MINOR|VM_FAULT_WRITE;
}
}
pte_unmap(page_table);
@@ -1283,6 +1292,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct * vma,
/*
* Re-check the pte - we dropped the lock
*/
+ ret = VM_FAULT_MINOR;
spin_lock(&mm->page_table_lock);
page_table = pte_offset_map(pmd, address);
if (likely(pte_same(*page_table, pte))) {
@@ -1299,12 +1309,13 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct * vma,
/* Free the old page.. */
new_page = old_page;
+ ret |= VM_FAULT_WRITE;
}
pte_unmap(page_table);
page_cache_release(new_page);
page_cache_release(old_page);
spin_unlock(&mm->page_table_lock);
- return VM_FAULT_MINOR;
+ return ret;
no_new_page:
page_cache_release(old_page);
@@ -1996,7 +2007,6 @@ static inline int handle_pte_fault(struct mm_struct *mm,
if (write_access) {
if (!pte_write(entry))
return do_wp_page(mm, vma, address, pte, pmd, entry);
-
entry = pte_mkdirty(entry);
}
entry = pte_mkyoung(entry);
@@ -2011,7 +2021,7 @@ static inline int handle_pte_fault(struct mm_struct *mm,
/*
* By the time we get here, we already hold the mm semaphore
*/
-int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct * vma,
+int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct * vma,
unsigned long address, int write_access)
{
pgd_t *pgd;
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 1694845526b..b4eababc819 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -443,7 +443,7 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
struct mempolicy *new;
DECLARE_BITMAP(nodes, MAX_NUMNODES);
- if (mode > MPOL_MAX)
+ if (mode < 0 || mode > MPOL_MAX)
return -EINVAL;
err = get_nodes(nodes, nmask, maxnode, mode);
if (err)
diff --git a/mm/mmap.c b/mm/mmap.c
index da3fa90a0aa..404319477e7 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -143,7 +143,11 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
leave 3% of the size of this process for other processes */
allowed -= current->mm->total_vm / 32;
- if (atomic_read(&vm_committed_space) < allowed)
+ /*
+ * cast `allowed' as a signed long because vm_committed_space
+ * sometimes has a negative value
+ */
+ if (atomic_read(&vm_committed_space) < (long)allowed)
return 0;
vm_unacct_memory(pages);
diff --git a/mm/mremap.c b/mm/mremap.c
index ec7238a78f3..fc45dc9a617 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -229,6 +229,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
* since do_munmap() will decrement it by old_len == new_len
*/
mm->total_vm += new_len >> PAGE_SHIFT;
+ __vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT);
if (do_munmap(mm, old_addr, old_len) < 0) {
/* OOM: unable to split vma, just get accounts right */
@@ -243,7 +244,6 @@ static unsigned long move_vma(struct vm_area_struct *vma,
vma->vm_next->vm_flags |= VM_ACCOUNT;
}
- __vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT);
if (vm_flags & VM_LOCKED) {
mm->locked_vm += new_len >> PAGE_SHIFT;
if (new_len > old_len)
diff --git a/mm/nommu.c b/mm/nommu.c
index ce74452c02d..fd4e8df0f02 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1167,7 +1167,11 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
leave 3% of the size of this process for other processes */
allowed -= current->mm->total_vm / 32;
- if (atomic_read(&vm_committed_space) < allowed)
+ /*
+ * cast `allowed' as a signed long because vm_committed_space
+ * sometimes has a negative value
+ */
+ if (atomic_read(&vm_committed_space) < (long)allowed)
return 0;
vm_unacct_memory(pages);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 42bccfb8464..8d088371196 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1061,20 +1061,19 @@ unsigned int nr_free_pages_pgdat(pg_data_t *pgdat)
static unsigned int nr_free_zone_pages(int offset)
{
- pg_data_t *pgdat;
+ /* Just pick one node, since fallback list is circular */
+ pg_data_t *pgdat = NODE_DATA(numa_node_id());
unsigned int sum = 0;
- for_each_pgdat(pgdat) {
- struct zonelist *zonelist = pgdat->node_zonelists + offset;
- struct zone **zonep = zonelist->zones;
- struct zone *zone;
+ struct zonelist *zonelist = pgdat->node_zonelists + offset;
+ struct zone **zonep = zonelist->zones;
+ struct zone *zone;
- for (zone = *zonep++; zone; zone = *zonep++) {
- unsigned long size = zone->present_pages;
- unsigned long high = zone->pages_high;
- if (size > high)
- sum += size - high;
- }
+ for (zone = *zonep++; zone; zone = *zonep++) {
+ unsigned long size = zone->present_pages;
+ unsigned long high = zone->pages_high;
+ if (size > high)
+ sum += size - high;
}
return sum;
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-21 09:14:22 +0000