summaryrefslogtreecommitdiffstats
path: root/include/linux
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/mm.h2
-rw-r--r--include/linux/pagemap.h13
2 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 2862009f957..3bf46655b50 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -144,6 +144,7 @@ extern pgprot_t protection_map[16];
#define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */
#define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */
#define FAULT_FLAG_MKWRITE 0x04 /* Fault was mkwrite of existing pte */
+#define FAULT_FLAG_ALLOW_RETRY 0x08 /* Retry fault if blocking */
/*
* This interface is used by x86 PAT code to identify a pfn mapping that is
@@ -723,6 +724,7 @@ static inline int page_mapped(struct page *page)
#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
+#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
#define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index e12cdc6d79e..2d1ffe3cf1e 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -299,6 +299,8 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
extern void __lock_page(struct page *page);
extern int __lock_page_killable(struct page *page);
extern void __lock_page_nosync(struct page *page);
+extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
+ unsigned int flags);
extern void unlock_page(struct page *page);
static inline void __set_page_locked(struct page *page)
@@ -351,6 +353,17 @@ static inline void lock_page_nosync(struct page *page)
}
/*
+ * lock_page_or_retry - Lock the page, unless this would block and the
+ * caller indicated that it can handle a retry.
+ */
+static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm,
+ unsigned int flags)
+{
+ might_sleep();
+ return trylock_page(page) || __lock_page_or_retry(page, mm, flags);
+}
+
+/*
* This is exported only for wait_on_page_locked/wait_on_page_writeback.
* Never use this directly!
*/