summaryrefslogtreecommitdiffstats
path: root/mm
diff options
context:
space:
mode:
Diffstat (limited to 'mm')
-rw-r--r--mm/Kconfig2
-rw-r--r--mm/hugetlb.c236
-rw-r--r--mm/memory.c10
-rw-r--r--mm/readahead.c2
-rw-r--r--mm/shmem.c45
-rw-r--r--mm/truncate.c117
6 files changed, 354 insertions, 58 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index e742d06285b7..f5e698e30d4a 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -173,7 +173,7 @@ config HAVE_BOOTMEM_INFO_NODE
config MEMORY_HOTPLUG
bool "Allow for memory hot-add"
depends on SPARSEMEM || X86_64_ACPI_NUMA
- depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG
+ depends on ARCH_ENABLE_MEMORY_HOTPLUG
depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390)
config MEMORY_HOTPLUG_SPARSE
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e2bfbf73a551..aed085ad11a8 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -690,6 +690,23 @@ int PageHuge(struct page *page)
}
EXPORT_SYMBOL_GPL(PageHuge);
+pgoff_t __basepage_index(struct page *page)
+{
+ struct page *page_head = compound_head(page);
+ pgoff_t index = page_index(page_head);
+ unsigned long compound_idx;
+
+ if (!PageHuge(page_head))
+ return page_index(page);
+
+ if (compound_order(page_head) >= MAX_ORDER)
+ compound_idx = page_to_pfn(page) - page_to_pfn(page_head);
+ else
+ compound_idx = page - page_head;
+
+ return (index << compound_order(page_head)) + compound_idx;
+}
+
static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
{
struct page *page;
@@ -2931,15 +2948,6 @@ out_mutex:
return ret;
}
-/* Can be overriden by architectures */
-__attribute__((weak)) struct page *
-follow_huge_pud(struct mm_struct *mm, unsigned long address,
- pud_t *pud, int write)
-{
- BUG();
- return NULL;
-}
-
long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
struct page **pages, struct vm_area_struct **vmas,
unsigned long *position, unsigned long *nr_pages,
@@ -3169,6 +3177,216 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
hugetlb_acct_memory(h, -(chg - freed));
}
+#ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
+static unsigned long page_table_shareable(struct vm_area_struct *svma,
+ struct vm_area_struct *vma,
+ unsigned long addr, pgoff_t idx)
+{
+ unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) +
+ svma->vm_start;
+ unsigned long sbase = saddr & PUD_MASK;
+ unsigned long s_end = sbase + PUD_SIZE;
+
+ /* Allow segments to share if only one is marked locked */
+ unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED;
+ unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED;
+
+ /*
+ * match the virtual addresses, permission and the alignment of the
+ * page table page.
+ */
+ if (pmd_index(addr) != pmd_index(saddr) ||
+ vm_flags != svm_flags ||
+ sbase < svma->vm_start || svma->vm_end < s_end)
+ return 0;
+
+ return saddr;
+}
+
+static int vma_shareable(struct vm_area_struct *vma, unsigned long addr)
+{
+ unsigned long base = addr & PUD_MASK;
+ unsigned long end = base + PUD_SIZE;
+
+ /*
+ * check on proper vm_flags and page table alignment
+ */
+ if (vma->vm_flags & VM_MAYSHARE &&
+ vma->vm_start <= base && end <= vma->vm_end)
+ return 1;
+ return 0;
+}
+
+/*
+ * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc()
+ * and returns the corresponding pte. While this is not necessary for the
+ * !shared pmd case because we can allocate the pmd later as well, it makes the
+ * code much cleaner. pmd allocation is essential for the shared case because
+ * pud has to be populated inside the same i_mmap_mutex section - otherwise
+ * racing tasks could either miss the sharing (see huge_pte_offset) or select a
+ * bad pmd for sharing.
+ */
+pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
+{
+ struct vm_area_struct *vma = find_vma(mm, addr);
+ struct address_space *mapping = vma->vm_file->f_mapping;
+ pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
+ vma->vm_pgoff;
+ struct vm_area_struct *svma;
+ unsigned long saddr;
+ pte_t *spte = NULL;
+ pte_t *pte;
+
+ if (!vma_shareable(vma, addr))
+ return (pte_t *)pmd_alloc(mm, pud, addr);
+
+ mutex_lock(&mapping->i_mmap_mutex);
+ vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) {
+ if (svma == vma)
+ continue;
+
+ saddr = page_table_shareable(svma, vma, addr, idx);
+ if (saddr) {
+ spte = huge_pte_offset(svma->vm_mm, saddr);
+ if (spte) {
+ get_page(virt_to_page(spte));
+ break;
+ }
+ }
+ }
+
+ if (!spte)
+ goto out;
+
+ spin_lock(&mm->page_table_lock);
+ if (pud_none(*pud))
+ pud_populate(mm, pud,
+ (pmd_t *)((unsigned long)spte & PAGE_MASK));
+ else
+ put_page(virt_to_page(spte));
+ spin_unlock(&mm->page_table_lock);
+out:
+ pte = (pte_t *)pmd_alloc(mm, pud, addr);
+ mutex_unlock(&mapping->i_mmap_mutex);
+ return pte;
+}
+
+/*
+ * unmap huge page backed by shared pte.
+ *
+ * Hugetlb pte page is ref counted at the time of mapping. If pte is shared
+ * indicated by page_count > 1, unmap is achieved by clearing pud and
+ * decrementing the ref count. If count == 1, the pte page is not shared.
+ *
+ * called with vma->vm_mm->page_table_lock held.
+ *
+ * returns: 1 successfully unmapped a shared pte page
+ * 0 the underlying pte page is not shared, or it is the last user
+ */
+int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
+{
+ pgd_t *pgd = pgd_offset(mm, *addr);
+ pud_t *pud = pud_offset(pgd, *addr);
+
+ BUG_ON(page_count(virt_to_page(ptep)) == 0);
+ if (page_count(virt_to_page(ptep)) == 1)
+ return 0;
+
+ pud_clear(pud);
+ put_page(virt_to_page(ptep));
+ *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE;
+ return 1;
+}
+#define want_pmd_share() (1)
+#else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
+pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
+{
+ return NULL;
+}
+#define want_pmd_share() (0)
+#endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
+
+#ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+ unsigned long addr, unsigned long sz)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pte_t *pte = NULL;
+
+ pgd = pgd_offset(mm, addr);
+ pud = pud_alloc(mm, pgd, addr);
+ if (pud) {
+ if (sz == PUD_SIZE) {
+ pte = (pte_t *)pud;
+ } else {
+ BUG_ON(sz != PMD_SIZE);
+ if (want_pmd_share() && pud_none(*pud))
+ pte = huge_pmd_share(mm, addr, pud);
+ else
+ pte = (pte_t *)pmd_alloc(mm, pud, addr);
+ }
+ }
+ BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte));
+
+ return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd = NULL;
+
+ pgd = pgd_offset(mm, addr);
+ if (pgd_present(*pgd)) {
+ pud = pud_offset(pgd, addr);
+ if (pud_present(*pud)) {
+ if (pud_huge(*pud))
+ return (pte_t *)pud;
+ pmd = pmd_offset(pud, addr);
+ }
+ }
+ return (pte_t *) pmd;
+}
+
+struct page *
+follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+ pmd_t *pmd, int write)
+{
+ struct page *page;
+
+ page = pte_page(*(pte_t *)pmd);
+ if (page)
+ page += ((address & ~PMD_MASK) >> PAGE_SHIFT);
+ return page;
+}
+
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+ pud_t *pud, int write)
+{
+ struct page *page;
+
+ page = pte_page(*(pte_t *)pud);
+ if (page)
+ page += ((address & ~PUD_MASK) >> PAGE_SHIFT);
+ return page;
+}
+
+#else /* !CONFIG_ARCH_WANT_GENERAL_HUGETLB */
+
+/* Can be overriden by architectures */
+__attribute__((weak)) struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+ pud_t *pud, int write)
+{
+ BUG();
+ return NULL;
+}
+
+#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
+
#ifdef CONFIG_MEMORY_FAILURE
/* Should be called in hugetlb_lock */
diff --git a/mm/memory.c b/mm/memory.c
index 61a262b08e53..95d0cce63583 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4201,7 +4201,7 @@ void print_vma_addr(char *prefix, unsigned long ip)
up_read(&mm->mmap_sem);
}
-#ifdef CONFIG_PROVE_LOCKING
+#if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)
void might_fault(void)
{
/*
@@ -4213,13 +4213,17 @@ void might_fault(void)
if (segment_eq(get_fs(), KERNEL_DS))
return;
- might_sleep();
/*
* it would be nicer only to annotate paths which are not under
* pagefault_disable, however that requires a larger audit and
* providing helpers like get_user_atomic.
*/
- if (!in_atomic() && current->mm)
+ if (in_atomic())
+ return;
+
+ __might_sleep(__FILE__, __LINE__, 0);
+
+ if (current->mm)
might_lock_read(&current->mm->mmap_sem);
}
EXPORT_SYMBOL(might_fault);
diff --git a/mm/readahead.c b/mm/readahead.c
index daed28dd5830..829a77c62834 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -48,7 +48,7 @@ static void read_cache_pages_invalidate_page(struct address_space *mapping,
if (!trylock_page(page))
BUG();
page->mapping = mapping;
- do_invalidatepage(page, 0);
+ do_invalidatepage(page, 0, PAGE_CACHE_SIZE);
page->mapping = NULL;
unlock_page(page);
}
diff --git a/mm/shmem.c b/mm/shmem.c
index 5e6a8422658b..a87990cf9f94 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1798,10 +1798,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence)
}
}
- if (offset >= 0 && offset != file->f_pos) {
- file->f_pos = offset;
- file->f_version = 0;
- }
+ offset = vfs_setpos(file, offset, MAX_LFS_FILESIZE);
mutex_unlock(&inode->i_mutex);
return offset;
}
@@ -1939,6 +1936,13 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE);
if (inode) {
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ error = generic_acl_init(inode, dir);
+ if (error) {
+ iput(inode);
+ return error;
+ }
+#endif
error = security_inode_init_security(inode, dir,
&dentry->d_name,
shmem_initxattrs, NULL);
@@ -1948,6 +1952,33 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
return error;
}
}
+
+ error = 0;
+ dir->i_size += BOGO_DIRENT_SIZE;
+ dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+ d_instantiate(dentry, inode);
+ dget(dentry); /* Extra count - pin the dentry in core */
+ }
+ return error;
+}
+
+static int
+shmem_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ struct inode *inode;
+ int error = -ENOSPC;
+
+ inode = shmem_get_inode(dir->i_sb, dir, mode, 0, VM_NORESERVE);
+ if (inode) {
+ error = security_inode_init_security(inode, dir,
+ NULL,
+ shmem_initxattrs, NULL);
+ if (error) {
+ if (error != -EOPNOTSUPP) {
+ iput(inode);
+ return error;
+ }
+ }
#ifdef CONFIG_TMPFS_POSIX_ACL
error = generic_acl_init(inode, dir);
if (error) {
@@ -1957,10 +1988,7 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
#else
error = 0;
#endif
- dir->i_size += BOGO_DIRENT_SIZE;
- dir->i_ctime = dir->i_mtime = CURRENT_TIME;
- d_instantiate(dentry, inode);
- dget(dentry); /* Extra count - pin the dentry in core */
+ d_tmpfile(dentry, inode);
}
return error;
}
@@ -2723,6 +2751,7 @@ static const struct inode_operations shmem_dir_inode_operations = {
.rmdir = shmem_rmdir,
.mknod = shmem_mknod,
.rename = shmem_rename,
+ .tmpfile = shmem_tmpfile,
#endif
#ifdef CONFIG_TMPFS_XATTR
.setxattr = shmem_setxattr,
diff --git a/mm/truncate.c b/mm/truncate.c
index c75b736e54b7..e2e8a8a7eb9d 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -26,7 +26,8 @@
/**
* do_invalidatepage - invalidate part or all of a page
* @page: the page which is affected
- * @offset: the index of the truncation point
+ * @offset: start of the range to invalidate
+ * @length: length of the range to invalidate
*
* do_invalidatepage() is called when all or part of the page has become
* invalidated by a truncate operation.
@@ -37,24 +38,18 @@
* point. Because the caller is about to free (and possibly reuse) those
* blocks on-disk.
*/
-void do_invalidatepage(struct page *page, unsigned long offset)
+void do_invalidatepage(struct page *page, unsigned int offset,
+ unsigned int length)
{
- void (*invalidatepage)(struct page *, unsigned long);
+ void (*invalidatepage)(struct page *, unsigned int, unsigned int);
+
invalidatepage = page->mapping->a_ops->invalidatepage;
#ifdef CONFIG_BLOCK
if (!invalidatepage)
invalidatepage = block_invalidatepage;
#endif
if (invalidatepage)
- (*invalidatepage)(page, offset);
-}
-
-static inline void truncate_partial_page(struct page *page, unsigned partial)
-{
- zero_user_segment(page, partial, PAGE_CACHE_SIZE);
- cleancache_invalidate_page(page->mapping, page);
- if (page_has_private(page))
- do_invalidatepage(page, partial);
+ (*invalidatepage)(page, offset, length);
}
/*
@@ -103,7 +98,7 @@ truncate_complete_page(struct address_space *mapping, struct page *page)
return -EIO;
if (page_has_private(page))
- do_invalidatepage(page, 0);
+ do_invalidatepage(page, 0, PAGE_CACHE_SIZE);
cancel_dirty_page(page, PAGE_CACHE_SIZE);
@@ -185,11 +180,11 @@ int invalidate_inode_page(struct page *page)
* truncate_inode_pages_range - truncate range of pages specified by start & end byte offsets
* @mapping: mapping to truncate
* @lstart: offset from which to truncate
- * @lend: offset to which to truncate
+ * @lend: offset to which to truncate (inclusive)
*
* Truncate the page cache, removing the pages that are between
- * specified offsets (and zeroing out partial page
- * (if lstart is not page aligned)).
+ * specified offsets (and zeroing out partial pages
+ * if lstart or lend + 1 is not page aligned).
*
* Truncate takes two passes - the first pass is nonblocking. It will not
* block on page locks and it will not block on writeback. The second pass
@@ -200,35 +195,58 @@ int invalidate_inode_page(struct page *page)
* We pass down the cache-hot hint to the page freeing code. Even if the
* mapping is large, it is probably the case that the final pages are the most
* recently touched, and freeing happens in ascending file offset order.
+ *
+ * Note that since ->invalidatepage() accepts range to invalidate
+ * truncate_inode_pages_range is able to handle cases where lend + 1 is not
+ * page aligned properly.
*/
void truncate_inode_pages_range(struct address_space *mapping,
loff_t lstart, loff_t lend)
{
- const pgoff_t start = (lstart + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT;
- const unsigned partial = lstart & (PAGE_CACHE_SIZE - 1);
- struct pagevec pvec;
- pgoff_t index;
- pgoff_t end;
- int i;
+ pgoff_t start; /* inclusive */
+ pgoff_t end; /* exclusive */
+ unsigned int partial_start; /* inclusive */
+ unsigned int partial_end; /* exclusive */
+ struct pagevec pvec;
+ pgoff_t index;
+ int i;
cleancache_invalidate_inode(mapping);
if (mapping->nrpages == 0)
return;
- BUG_ON((lend & (PAGE_CACHE_SIZE - 1)) != (PAGE_CACHE_SIZE - 1));
- end = (lend >> PAGE_CACHE_SHIFT);
+ /* Offsets within partial pages */
+ partial_start = lstart & (PAGE_CACHE_SIZE - 1);
+ partial_end = (lend + 1) & (PAGE_CACHE_SIZE - 1);
+
+ /*
+ * 'start' and 'end' always covers the range of pages to be fully
+ * truncated. Partial pages are covered with 'partial_start' at the
+ * start of the range and 'partial_end' at the end of the range.
+ * Note that 'end' is exclusive while 'lend' is inclusive.
+ */
+ start = (lstart + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ if (lend == -1)
+ /*
+ * lend == -1 indicates end-of-file so we have to set 'end'
+ * to the highest possible pgoff_t and since the type is
+ * unsigned we're using -1.
+ */
+ end = -1;
+ else
+ end = (lend + 1) >> PAGE_CACHE_SHIFT;
pagevec_init(&pvec, 0);
index = start;
- while (index <= end && pagevec_lookup(&pvec, mapping, index,
- min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) {
+ while (index < end && pagevec_lookup(&pvec, mapping, index,
+ min(end - index, (pgoff_t)PAGEVEC_SIZE))) {
mem_cgroup_uncharge_start();
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
/* We rely upon deletion not changing page->index */
index = page->index;
- if (index > end)
+ if (index >= end)
break;
if (!trylock_page(page))
@@ -247,27 +265,56 @@ void truncate_inode_pages_range(struct address_space *mapping,
index++;
}
- if (partial) {
+ if (partial_start) {
struct page *page = find_lock_page(mapping, start - 1);
if (page) {
+ unsigned int top = PAGE_CACHE_SIZE;
+ if (start > end) {
+ /* Truncation within a single page */
+ top = partial_end;
+ partial_end = 0;
+ }
wait_on_page_writeback(page);
- truncate_partial_page(page, partial);
+ zero_user_segment(page, partial_start, top);
+ cleancache_invalidate_page(mapping, page);
+ if (page_has_private(page))
+ do_invalidatepage(page, partial_start,
+ top - partial_start);
unlock_page(page);
page_cache_release(page);
}
}
+ if (partial_end) {
+ struct page *page = find_lock_page(mapping, end);
+ if (page) {
+ wait_on_page_writeback(page);
+ zero_user_segment(page, 0, partial_end);
+ cleancache_invalidate_page(mapping, page);
+ if (page_has_private(page))
+ do_invalidatepage(page, 0,
+ partial_end);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ }
+ /*
+ * If the truncation happened within a single page no pages
+ * will be released, just zeroed, so we can bail out now.
+ */
+ if (start >= end)
+ return;
index = start;
for ( ; ; ) {
cond_resched();
if (!pagevec_lookup(&pvec, mapping, index,
- min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) {
+ min(end - index, (pgoff_t)PAGEVEC_SIZE))) {
if (index == start)
break;
index = start;
continue;
}
- if (index == start && pvec.pages[0]->index > end) {
+ if (index == start && pvec.pages[0]->index >= end) {
pagevec_release(&pvec);
break;
}
@@ -277,7 +324,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
/* We rely upon deletion not changing page->index */
index = page->index;
- if (index > end)
+ if (index >= end)
break;
lock_page(page);
@@ -598,10 +645,8 @@ void truncate_pagecache_range(struct inode *inode, loff_t lstart, loff_t lend)
* This rounding is currently just for example: unmap_mapping_range
* expands its hole outwards, whereas we want it to contract the hole
* inwards. However, existing callers of truncate_pagecache_range are
- * doing their own page rounding first; and truncate_inode_pages_range
- * currently BUGs if lend is not pagealigned-1 (it handles partial
- * page at start of hole, but not partial page at end of hole). Note
- * unmap_mapping_range allows holelen 0 for all, and we allow lend -1.
+ * doing their own page rounding first. Note that unmap_mapping_range
+ * allows holelen 0 for all, and we allow lend -1 for end of file.
*/
/*