[PATCH 4/5] SCSI: add cpu cache flushes after kmapping and modifying a page

[Tejun Heo <htejun@gmail.com>]

Add calls to flush_kernel_dcache_page() after CPU has kmapped and
modified a page.  This fixes PIO cache coherency bugs on architectures
with aliased caches.

Signed-off-by: Tejun Heo <htejun@gmail.com>

---

 drivers/scsi/3w-9xxx.c        |    1 +
 drivers/scsi/3w-xxxx.c        |    1 +
 drivers/scsi/aacraid/aachba.c |    4 +++-
 drivers/scsi/ide-scsi.c       |    1 +
 drivers/scsi/ips.c            |    2 ++
 drivers/scsi/iscsi_tcp.c      |    1 +
 drivers/scsi/megaraid.c       |    2 ++
 drivers/scsi/qlogicpti.c      |    1 +
 drivers/scsi/scsi_debug.c     |    1 +
 drivers/scsi/scsi_lib.c       |    1 +
 10 files changed, 14 insertions(+), 1 deletions(-)

9b4bdd1409efb726d4a6561a4f7e2aff878ab4f4
diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index caeb6d2..172f16b 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -1948,6 +1948,7 @@ static void twa_scsiop_execute_scsi_comp
 			local_irq_save(flags);
 			buf = kmap_atomic(sg->page, KM_IRQ0) + sg->offset;
 			memcpy(buf, tw_dev->generic_buffer_virt[request_id], sg->length);
+			flush_kernel_dcache_page(kmap_atomic_to_page(buf - sg->offset));
 			kunmap_atomic(buf - sg->offset, KM_IRQ0);
 			local_irq_restore(flags);
 		}
diff --git a/drivers/scsi/3w-xxxx.c b/drivers/scsi/3w-xxxx.c
index e8e41e6..8449551 100644
--- a/drivers/scsi/3w-xxxx.c
+++ b/drivers/scsi/3w-xxxx.c
@@ -1527,6 +1527,7 @@ static void tw_transfer_internal(TW_Devi
 		struct scatterlist *sg;
 
 		sg = (struct scatterlist *)cmd->request_buffer;
+		flush_kernel_dcache_page(kmap_atomic_to_page(buf - sg->offset));
 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
 		local_irq_restore(flags);
 	}
diff --git a/drivers/scsi/aacraid/aachba.c b/drivers/scsi/aacraid/aachba.c
index 642a3b4..b7c00b8 100644
--- a/drivers/scsi/aacraid/aachba.c
+++ b/drivers/scsi/aacraid/aachba.c
@@ -376,8 +376,10 @@ static void aac_internal_transfer(struct
 
 	memcpy(buf + offset, data, transfer_len - offset);
 
-	if (scsicmd->use_sg) 
+	if (scsicmd->use_sg) {
+		flush_kernel_dcache_page(kmap_atomic_to_page(buf - sg->offset));
 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
+	}
 
 }
 
diff --git a/drivers/scsi/ide-scsi.c b/drivers/scsi/ide-scsi.c
index 39b760a..9c28b95 100644
--- a/drivers/scsi/ide-scsi.c
+++ b/drivers/scsi/ide-scsi.c
@@ -189,6 +189,7 @@ static void idescsi_input_buffers (ide_d
 					pc->sg->offset;
 			drive->hwif->atapi_input_bytes(drive,
 						buf + pc->b_count, count);
+			flush_kernel_dcache_page(kmap_atomic_to_page(buf - pc->sg->offset));
 			kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
 			local_irq_restore(flags);
 		} else {
diff --git a/drivers/scsi/ips.c b/drivers/scsi/ips.c
index a4c0b04..29eb3f0 100644
--- a/drivers/scsi/ips.c
+++ b/drivers/scsi/ips.c
@@ -3682,6 +3682,8 @@ ips_scmd_buf_write(Scsi_Cmnd * scmd, voi
 			local_irq_save(flags);
 			buffer = kmap_atomic(sg[i].page, KM_IRQ0) + sg[i].offset;
 			memcpy(buffer, &cdata[xfer_cnt], min_cnt);
+                        flush_kernel_dcache_page(
+                                kmap_atomic_to_page(buffer - sg[i].offset));
 			kunmap_atomic(buffer - sg[i].offset, KM_IRQ0);
 			local_irq_restore(flags);
 
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 2068b66..ae9784c 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -945,6 +945,7 @@ static int iscsi_scsi_data_in(struct isc
 		dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
 		rc = iscsi_ctask_copy(conn, ctask, dest + sg[i].offset,
 				      sg[i].length, offset);
+		flush_kernel_dcache_page(kmap_atomic_to_page(dest));
 		kunmap_atomic(dest, KM_SOFTIRQ0);
 		if (rc == -EAGAIN)
 			/* continue with the next SKB/PDU */
diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index de35ffe..7cb7590 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -671,6 +671,8 @@ #endif
 				struct scatterlist *sg;
 
 				sg = (struct scatterlist *)cmd->request_buffer;
+				flush_kernel_dcache_page(
+					kmap_atomic_to_page(buf - sg->offset));
 				kunmap_atomic(buf - sg->offset, KM_IRQ0);
 			}
 			cmd->result = (DID_OK << 16);
diff --git a/drivers/scsi/qlogicpti.c b/drivers/scsi/qlogicpti.c
index c7e78dc..f8201f2 100644
--- a/drivers/scsi/qlogicpti.c
+++ b/drivers/scsi/qlogicpti.c
@@ -1146,6 +1146,7 @@ static void scsi_rbuf_put(struct scsi_cm
 		struct scatterlist *sg;
 
 		sg = (struct scatterlist *) cmd->request_buffer;
+		flush_kernel_dcache_page(kmap_atomic_to_page(buf - sg->offset));
 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
 	}
 }
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 5a5d2af..88543db 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -511,6 +511,7 @@ static int fill_from_dev_buffer(struct s
 				len = arr_len - req_len;
 			}
 			memcpy(kaddr_off, arr + req_len, len);
+			flush_kernel_dcache_page(kmap_atomic_to_page(kaddr));
 			kunmap_atomic(kaddr, KM_USER0);
 			act_len += len;
 		}
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 764a8b3..8bb2f6c 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -945,6 +945,7 @@ void scsi_io_completion(struct scsi_cmnd
 			unsigned long flags;
 			char *to = bio_kmap_irq(req->bio, &flags);
 			memcpy(to, cmd->buffer, cmd->bufflen);
+			flush_kernel_dcache_page(kmap_atomic_to_page(to));
 			bio_kunmap_irq(to, &flags);
 		}
 		kfree(cmd->buffer);
-- 
1.3.2