aboutsummaryrefslogtreecommitdiff
path: root/drivers/scsi/scsi_lib.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
-rw-r--r--drivers/scsi/scsi_lib.c66
1 files changed, 63 insertions, 3 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 3574ba935af..701a328f7be 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -16,6 +16,7 @@
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/delay.h>
+#include <linux/hardirq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_dbg.h>
@@ -436,6 +437,7 @@ free_bios:
* scsi_execute_async - insert request
* @sdev: scsi device
* @cmd: scsi command
+ * @cmd_len: length of scsi cdb
* @data_direction: data direction
* @buffer: data buffer (this can be a kernel buffer or scatterlist)
* @bufflen: len of buffer
@@ -445,7 +447,7 @@ free_bios:
* @flags: or into request flags
**/
int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
- int data_direction, void *buffer, unsigned bufflen,
+ int cmd_len, int data_direction, void *buffer, unsigned bufflen,
int use_sg, int timeout, int retries, void *privdata,
void (*done)(void *, char *, int, int), gfp_t gfp)
{
@@ -472,7 +474,7 @@ int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
if (err)
goto free_req;
- req->cmd_len = COMMAND_SIZE(cmd[0]);
+ req->cmd_len = cmd_len;
memcpy(req->cmd, cmd, req->cmd_len);
req->sense = sioc->sense;
req->sense_len = 0;
@@ -1496,7 +1498,7 @@ static void scsi_kill_request(struct request *req, request_queue_t *q)
static void scsi_softirq_done(struct request *rq)
{
struct scsi_cmnd *cmd = rq->completion_data;
- unsigned long wait_for = cmd->allowed * cmd->timeout_per_command;
+ unsigned long wait_for = (cmd->allowed + 1) * cmd->timeout_per_command;
int disposition;
INIT_LIST_HEAD(&cmd->eh_entry);
@@ -2247,3 +2249,61 @@ scsi_target_unblock(struct device *dev)
device_for_each_child(dev, NULL, target_unblock);
}
EXPORT_SYMBOL_GPL(scsi_target_unblock);
+
+
+struct work_queue_work {
+ struct work_struct work;
+ void (*fn)(void *);
+ void *data;
+};
+
+static void execute_in_process_context_work(void *data)
+{
+ void (*fn)(void *data);
+ struct work_queue_work *wqw = data;
+
+ fn = wqw->fn;
+ data = wqw->data;
+
+ kfree(wqw);
+
+ fn(data);
+}
+
+/**
+ * scsi_execute_in_process_context - reliably execute the routine with user context
+ * @fn: the function to execute
+ * @data: data to pass to the function
+ *
+ * Executes the function immediately if process context is available,
+ * otherwise schedules the function for delayed execution.
+ *
+ * Returns: 0 - function was executed
+ * 1 - function was scheduled for execution
+ * <0 - error
+ */
+int scsi_execute_in_process_context(void (*fn)(void *data), void *data)
+{
+ struct work_queue_work *wqw;
+
+ if (!in_interrupt()) {
+ fn(data);
+ return 0;
+ }
+
+ wqw = kmalloc(sizeof(struct work_queue_work), GFP_ATOMIC);
+
+ if (unlikely(!wqw)) {
+ printk(KERN_ERR "Failed to allocate memory\n");
+ WARN_ON(1);
+ return -ENOMEM;
+ }
+
+ INIT_WORK(&wqw->work, execute_in_process_context_work, wqw);
+ wqw->fn = fn;
+ wqw->data = data;
+ schedule_work(&wqw->work);
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(scsi_execute_in_process_context);