Because the MTD core might split up a read() or write() from userspace
into several calls to the driver, we may fail to get a token but already
have done some work, best to return -EINTR back to userspace and have
them decide what to do.
Signed-off-by: Cyril Bur <cyril...@gmail.com>
Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com>
---
drivers/mtd/devices/powernv_flash.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/mtd/devices/powernv_flash.c
b/drivers/mtd/devices/powernv_flash.c
index 4dd3b5d2feb2..3343d4f5c4f3 100644
--- a/drivers/mtd/devices/powernv_flash.c
+++ b/drivers/mtd/devices/powernv_flash.c
@@ -47,6 +47,11 @@ enum flash_op {
FLASH_OP_ERASE,
};
+/*
+ * Don't return -ERESTARTSYS if we can't get a token, the MTD core
+ * might have split up the call from userspace and called into the
+ * driver more than once, we'll already have done some amount of work.
+ */
static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op,
loff_t offset, size_t len, size_t *retlen, u_char *buf)
{
@@ -63,6 +68,8 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum
flash_op op,
if (token < 0) {
if (token != -ERESTARTSYS)
dev_err(dev, "Failed to get an async token\n");
+ else
+ token = -EINTR;
return token;
}
--
2.15.0
