@@ -90,16 +90,34 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op,
goto out_success;
if (rc != OPAL_ASYNC_COMPLETION) {
- dev_err(dev, "opal_flash_async_op(op=%d) failed (rc %d)\n",
+ if (rc != OPAL_BUSY)
+ dev_err(dev, "opal_flash_async_op(op=%d) failed (rc %d)\n",
op, rc);
- rc = -EIO;
+ rc = opal_error_code(rc);
goto out;
}
- rc = opal_async_wait_response(token, &msg);
+ rc = opal_async_wait_response_interruptible(token, &msg);
if (rc) {
- dev_err(dev, "opal async wait failed (rc %d)\n", rc);
- rc = -EIO;
+ /*
+ * Awkward, we've been interrupted but we cannot return. If we
+ * do return the mtd core will free the buffer we've just
+ * passed to OPAL but OPAL will continue to read or write from
+ * that memory.
+ * Future work will introduce a call to tell OPAL to stop
+ * using the buffer.
+ * It may be tempting to ultimately return 0 if we're doing a
+ * read or a write since we are going to end up waiting until
+ * OPAL is done. However, because the MTD core sends us the
+ * userspace request in chunks, we must report EINTR so that
+ * it doesn't just send us the next chunk, thus defeating the
+ * point of the _interruptible wait.
+ */
+ rc = -EINTR;
+ if (op == FLASH_OP_READ || op == FLASH_OP_WRITE) {
+ if (opal_async_wait_response(token, &msg))
+ dev_err(dev, "opal async wait failed (rc %d)\n", rc);
+ }
goto out;
}
The OPAL calls performed in this driver shouldn't be using opal_async_wait_response() as this performs a wait_event() which, on long running OPAL calls could result in hung task warnings. wait_event() prevents timely signal delivery which is also undesirable. This patch also attempts to quieten down the use of dev_err() when errors haven't actually occurred and also to return better information up the stack rather than always -EIO. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> --- drivers/mtd/devices/powernv_flash.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-)