[SCSI] vmw_pvscsi: Fix pvscsi_abort() function.
This change ensures that pvscsi_abort() function returns SUCCESS
only when the command in question was actually completed, otherwise
returns FAILURE. The code before change, was causing a bug where
driver tries to complete a command to the mid-layer while the mid-layer
has already requested the driver to abort that command, in response
to which the driver has responded with SUCCESS causing mid-layer
to free the command struct.
Signed-off-by: Arvind Kumar <arvindkumar@vmware.com>
Tested-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/vmw_pvscsi.c b/drivers/scsi/vmw_pvscsi.c
index b9755ec..7c5abd7 100644
--- a/drivers/scsi/vmw_pvscsi.c
+++ b/drivers/scsi/vmw_pvscsi.c
@@ -1,7 +1,7 @@
/*
* Linux driver for VMware's para-virtualized SCSI HBA.
*
- * Copyright (C) 2008-2009, VMware, Inc. All Rights Reserved.
+ * Copyright (C) 2008-2014, VMware, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
@@ -62,6 +62,7 @@
dma_addr_t dataPA;
dma_addr_t sensePA;
dma_addr_t sglPA;
+ struct completion *abort_cmp;
};
struct pvscsi_adapter {
@@ -177,6 +178,7 @@
struct pvscsi_ctx *ctx)
{
ctx->cmd = NULL;
+ ctx->abort_cmp = NULL;
list_add(&ctx->list, &adapter->cmd_pool);
}
@@ -496,15 +498,27 @@
{
struct pvscsi_ctx *ctx;
struct scsi_cmnd *cmd;
+ struct completion *abort_cmp;
u32 btstat = e->hostStatus;
u32 sdstat = e->scsiStatus;
ctx = pvscsi_get_context(adapter, e->context);
cmd = ctx->cmd;
+ abort_cmp = ctx->abort_cmp;
pvscsi_unmap_buffers(adapter, ctx);
pvscsi_release_context(adapter, ctx);
- cmd->result = 0;
+ if (abort_cmp) {
+ /*
+ * The command was requested to be aborted. Just signal that
+ * the request completed and swallow the actual cmd completion
+ * here. The abort handler will post a completion for this
+ * command indicating that it got successfully aborted.
+ */
+ complete(abort_cmp);
+ return;
+ }
+ cmd->result = 0;
if (sdstat != SAM_STAT_GOOD &&
(btstat == BTSTAT_SUCCESS ||
btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
@@ -726,6 +740,8 @@
struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
struct pvscsi_ctx *ctx;
unsigned long flags;
+ int result = SUCCESS;
+ DECLARE_COMPLETION_ONSTACK(abort_cmp);
scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
adapter->host->host_no, cmd);
@@ -748,13 +764,40 @@
goto out;
}
- pvscsi_abort_cmd(adapter, ctx);
+ /*
+ * Mark that the command has been requested to be aborted and issue
+ * the abort.
+ */
+ ctx->abort_cmp = &abort_cmp;
- pvscsi_process_completion_ring(adapter);
+ pvscsi_abort_cmd(adapter, ctx);
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+ /* Wait for 2 secs for the completion. */
+ wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ if (!completion_done(&abort_cmp)) {
+ /*
+ * Failed to abort the command, unmark the fact that it
+ * was requested to be aborted.
+ */
+ ctx->abort_cmp = NULL;
+ result = FAILED;
+ scmd_printk(KERN_DEBUG, cmd,
+ "Failed to get completion for aborted cmd %p\n",
+ cmd);
+ goto out;
+ }
+
+ /*
+ * Successfully aborted the command.
+ */
+ cmd->result = (DID_ABORT << 16);
+ cmd->scsi_done(cmd);
out:
spin_unlock_irqrestore(&adapter->hw_lock, flags);
- return SUCCESS;
+ return result;
}
/*