3w-xxxx: fix command completion race
authorChristoph Hellwig <hch@lst.de>
Thu, 23 Apr 2015 07:48:50 +0000 (09:48 +0200)
committerSasha Levin <sasha.levin@oracle.com>
Sun, 17 May 2015 23:12:41 +0000 (19:12 -0400)
[ Upstream commit 9cd9554615cba14f0877cc9972a6537ad2bdde61 ]

The 3w-xxxx driver needs to tear down the dma mappings before returning
the command to the midlayer, as there is no guarantee the sglist and
count are valid after that point.  Also remove the dma mapping helpers
which have another inherent race due to the request_id index.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Acked-by: Adam Radford <aradford@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
drivers/scsi/3w-xxxx.c
drivers/scsi/3w-xxxx.h

index 752624e6bc0022807c6265539cad6d8b42d1611f..b327742b95ef82e31ecd09a5193f48772b235970 100644 (file)
@@ -1284,32 +1284,6 @@ static int tw_initialize_device_extension(TW_Device_Extension *tw_dev)
        return 0;
 } /* End tw_initialize_device_extension() */
 
-static int tw_map_scsi_sg_data(struct pci_dev *pdev, struct scsi_cmnd *cmd)
-{
-       int use_sg;
-
-       dprintk(KERN_WARNING "3w-xxxx: tw_map_scsi_sg_data()\n");
-
-       use_sg = scsi_dma_map(cmd);
-       if (use_sg < 0) {
-               printk(KERN_WARNING "3w-xxxx: tw_map_scsi_sg_data(): pci_map_sg() failed.\n");
-               return 0;
-       }
-
-       cmd->SCp.phase = TW_PHASE_SGLIST;
-       cmd->SCp.have_data_in = use_sg;
-
-       return use_sg;
-} /* End tw_map_scsi_sg_data() */
-
-static void tw_unmap_scsi_data(struct pci_dev *pdev, struct scsi_cmnd *cmd)
-{
-       dprintk(KERN_WARNING "3w-xxxx: tw_unmap_scsi_data()\n");
-
-       if (cmd->SCp.phase == TW_PHASE_SGLIST)
-               scsi_dma_unmap(cmd);
-} /* End tw_unmap_scsi_data() */
-
 /* This function will reset a device extension */
 static int tw_reset_device_extension(TW_Device_Extension *tw_dev)
 {
@@ -1332,8 +1306,8 @@ static int tw_reset_device_extension(TW_Device_Extension *tw_dev)
                        srb = tw_dev->srb[i];
                        if (srb != NULL) {
                                srb->result = (DID_RESET << 16);
-                               tw_dev->srb[i]->scsi_done(tw_dev->srb[i]);
-                               tw_unmap_scsi_data(tw_dev->tw_pci_dev, tw_dev->srb[i]);
+                               scsi_dma_unmap(srb);
+                               srb->scsi_done(srb);
                        }
                }
        }
@@ -1780,8 +1754,8 @@ static int tw_scsiop_read_write(TW_Device_Extension *tw_dev, int request_id)
        command_packet->byte8.io.lba = lba;
        command_packet->byte6.block_count = num_sectors;
 
-       use_sg = tw_map_scsi_sg_data(tw_dev->tw_pci_dev, tw_dev->srb[request_id]);
-       if (!use_sg)
+       use_sg = scsi_dma_map(srb);
+       if (use_sg <= 0)
                return 1;
 
        scsi_for_each_sg(tw_dev->srb[request_id], sg, use_sg, i) {
@@ -1968,9 +1942,6 @@ static int tw_scsi_queue_lck(struct scsi_cmnd *SCpnt, void (*done)(struct scsi_c
        /* Save the scsi command for use by the ISR */
        tw_dev->srb[request_id] = SCpnt;
 
-       /* Initialize phase to zero */
-       SCpnt->SCp.phase = TW_PHASE_INITIAL;
-
        switch (*command) {
                case READ_10:
                case READ_6:
@@ -2198,12 +2169,11 @@ static irqreturn_t tw_interrupt(int irq, void *dev_instance)
 
                                /* Now complete the io */
                                if ((error != TW_ISR_DONT_COMPLETE)) {
+                                       scsi_dma_unmap(tw_dev->srb[request_id]);
+                                       tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
                                        tw_dev->state[request_id] = TW_S_COMPLETED;
                                        tw_state_request_finish(tw_dev, request_id);
                                        tw_dev->posted_request_count--;
-                                       tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
-                                       
-                                       tw_unmap_scsi_data(tw_dev->tw_pci_dev, tw_dev->srb[request_id]);
                                }
                        }
                                
index 29b0b84ed69e888b1939c57dde7e60589506e992..6f65e663d3932108edaed6b75eba328d469f4fce 100644 (file)
@@ -195,11 +195,6 @@ static unsigned char tw_sense_table[][4] =
 #define TW_AEN_SMART_FAIL        0x000F
 #define TW_AEN_SBUF_FAIL         0x0024
 
-/* Phase defines */
-#define TW_PHASE_INITIAL 0
-#define TW_PHASE_SINGLE 1
-#define TW_PHASE_SGLIST 2
-
 /* Misc defines */
 #define TW_ALIGNMENT_6000                    64 /* 64 bytes */
 #define TW_ALIGNMENT_7000                     4  /* 4 bytes */