[RFC] [PATCH] Fix up needless kmap:s

[Pierre Ossman <drzeus-list@drzeus.cx>]

Hi Alex,

I'd like you to test and comment on the following patch.

Rgds
-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
  PulseAudio, core developer          http://pulseaudio.org
  rdesktop, core developer          http://www.rdesktop.org

>From c8467c6b0ea0443f948c0ece281e1ca8e92f6ea7 Mon Sep 17 00:00:00 2001
From: Pierre Ossman <drzeus@drzeus.cx>
Date: Sat, 3 Feb 2007 13:36:41 +0100
Subject: [PATCH] mmc: tifm: replace kmap with page_address

Since we actively avoid highmem, calling kmap_atomic() instead
of page_address() is effectively only obfuscation.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
---
 drivers/mmc/tifm_sd.c |   15 ++++-----------
 1 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/tifm_sd.c b/drivers/mmc/tifm_sd.c
index 7e607b7..e65f8a0 100644
--- a/drivers/mmc/tifm_sd.c
+++ b/drivers/mmc/tifm_sd.c
@@ -107,14 +107,9 @@ struct tifm_sd {
 
 };
 
-static char* tifm_sd_kmap_atomic(struct mmc_data *data)
+static char* tifm_sd_data_buffer(struct mmc_data *data)
 {
-	return kmap_atomic(data->sg->page, KM_BIO_SRC_IRQ) + data->sg->offset;
-}
-
-static void tifm_sd_kunmap_atomic(char *buffer, struct mmc_data *data)
-{
-	kunmap_atomic(buffer - data->sg->offset, KM_BIO_SRC_IRQ);
+	return page_address(data->sg->page) + data->sg->offset;
 }
 
 static int tifm_sd_transfer_data(struct tifm_dev *sock, struct tifm_sd *host,
@@ -127,18 +122,17 @@ static int tifm_sd_transfer_data(struct tifm_dev *sock, struct tifm_sd *host,
 	if (host_status & TIFM_MMCSD_BRS) {
 		/* in non-dma rx mode BRS fires when fifo is still not empty */
 		if (no_dma && (cmd->data->flags & MMC_DATA_READ)) {
-			buffer = tifm_sd_kmap_atomic(host->req->data);
+			buffer = tifm_sd_data_buffer(host->req->data);
 			while (host->buffer_size > host->buffer_pos) {
 				t_val = readl(sock->addr + SOCK_MMCSD_DATA);
 				buffer[host->buffer_pos++] = t_val & 0xff;
 				buffer[host->buffer_pos++] =
 							(t_val >> 8) & 0xff;
 			}
-			tifm_sd_kunmap_atomic(buffer, host->req->data);
 		}
 		return 1;
 	} else if (no_dma) {
-		buffer = tifm_sd_kmap_atomic(host->req->data);
+		buffer = tifm_sd_data_buffer(host->req->data);
 		if ((cmd->data->flags & MMC_DATA_READ) &&
 				(host_status & TIFM_MMCSD_AF)) {
 			for (cnt = 0; cnt < TIFM_MMCSD_FIFO_SIZE; cnt++) {
@@ -163,7 +157,6 @@ static int tifm_sd_transfer_data(struct tifm_dev *sock, struct tifm_sd *host,
 				}
 			}
 		}
-		tifm_sd_kunmap_atomic(buffer, host->req->data);
 	}
 	return 0;
 }
-- 
1.4.4.2