mm: mark all calls into the vmalloc subsystem as potentially sleeping

[mirror_ubuntu-artful-kernel.git] / mm / shmem.c

diff --git a/mm/shmem.c b/mm/shmem.c
index 166ebf5d2bceda1bdc9a824b6b3040f28588a171..abd7403aba41f0001e6724c640f5e4095a63c142 100644 (file)
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -300,18 +300,19 @@ void shmem_uncharge(struct inode *inode, long pages)
 static int shmem_radix_tree_replace(struct address_space *mapping,
                        pgoff_t index, void *expected, void *replacement)
 {
+       struct radix_tree_node *node;
        void **pslot;
        void *item;
 
        VM_BUG_ON(!expected);
        VM_BUG_ON(!replacement);
-       pslot = radix_tree_lookup_slot(&mapping->page_tree, index);
-       if (!pslot)
+       item = __radix_tree_lookup(&mapping->page_tree, index, &node, &pslot);
+       if (!item)
                return -ENOENT;
-       item = radix_tree_deref_slot_protected(pslot, &mapping->tree_lock);
        if (item != expected)
                return -ENOENT;
-       radix_tree_replace_slot(pslot, replacement);
+       __radix_tree_replace(&mapping->page_tree, node, pslot,
+                            replacement, NULL, NULL);
        return 0;
 }
 
@@ -370,6 +371,7 @@ static bool shmem_confirm_swap(struct address_space *mapping,
 
 int shmem_huge __read_mostly;
 
+#if defined(CONFIG_SYSFS) || defined(CONFIG_TMPFS)
 static int shmem_parse_huge(const char *str)
 {
        if (!strcmp(str, "never"))
@@ -407,6 +409,7 @@ static const char *shmem_format_huge(int huge)
                return "bad_val";
        }
 }
+#endif
 
 static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo,
                struct shrink_control *sc, unsigned long nr_to_split)
@@ -1539,7 +1542,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
        struct mm_struct *fault_mm, int *fault_type)
 {
        struct address_space *mapping = inode->i_mapping;
-       struct shmem_inode_info *info;
+       struct shmem_inode_info *info = SHMEM_I(inode);
        struct shmem_sb_info *sbinfo;
        struct mm_struct *charge_mm;
        struct mem_cgroup *memcg;
@@ -1589,7 +1592,6 @@ repeat:
         * Fast cache lookup did not find it:
         * bring it back from swap or allocate.
         */
-       info = SHMEM_I(inode);
        sbinfo = SHMEM_SB(inode->i_sb);
        charge_mm = fault_mm ? : current->mm;
 
@@ -1837,7 +1839,6 @@ unlock:
                put_page(page);
        }
        if (error == -ENOSPC && !once++) {
-               info = SHMEM_I(inode);
                spin_lock_irq(&info->lock);
                shmem_recalc_inode(inode);
                spin_unlock_irq(&info->lock);
@@ -1848,6 +1849,18 @@ unlock:
        return error;
 }
 
+/*
+ * This is like autoremove_wake_function, but it removes the wait queue
+ * entry unconditionally - even if something else had already woken the
+ * target.
+ */
+static int synchronous_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key)
+{
+       int ret = default_wake_function(wait, mode, sync, key);
+       list_del_init(&wait->task_list);
+       return ret;
+}
+
 static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
        struct inode *inode = file_inode(vma->vm_file);
@@ -1883,7 +1896,7 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                    vmf->pgoff >= shmem_falloc->start &&
                    vmf->pgoff < shmem_falloc->next) {
                        wait_queue_head_t *shmem_falloc_waitq;
-                       DEFINE_WAIT(shmem_fault_wait);
+                       DEFINE_WAIT_FUNC(shmem_fault_wait, synchronous_wake_function);
 
                        ret = VM_FAULT_NOPAGE;
                        if ((vmf->flags & FAULT_FLAG_ALLOW_RETRY) &&
@@ -2665,6 +2678,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
                spin_lock(&inode->i_lock);
                inode->i_private = NULL;
                wake_up_all(&shmem_falloc_waitq);
+               WARN_ON_ONCE(!list_empty(&shmem_falloc_waitq.task_list));
                spin_unlock(&inode->i_lock);
                error = 0;
                goto out;