tifm_sd: use kmap_atomic instead of kmap for PIO data buffer
Data buffer for PIO transfer used to be mapped in advance with kmap.
Abolish it in favor of on-demand kmap_atomic.
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/tifm_sd.c b/drivers/mmc/tifm_sd.c
index f22c396..3e76277 100644
--- a/drivers/mmc/tifm_sd.c
+++ b/drivers/mmc/tifm_sd.c
@@ -103,38 +103,51 @@
wait_queue_head_t can_eject;
size_t written_blocks;
- char *buffer;
size_t buffer_size;
size_t buffer_pos;
};
+static char* tifm_sd_kmap_atomic(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);
+}
+
static int tifm_sd_transfer_data(struct tifm_dev *sock, struct tifm_sd *host,
unsigned int host_status)
{
struct mmc_command *cmd = host->req->cmd;
unsigned int t_val = 0, cnt = 0;
+ char *buffer;
if (host_status & TIFM_MMCSD_BRS) {
/* in non-dma rx mode BRS fires when fifo is still not empty */
- if (host->buffer && (cmd->data->flags & MMC_DATA_READ)) {
+ if (no_dma && (cmd->data->flags & MMC_DATA_READ)) {
+ buffer = tifm_sd_kmap_atomic(host->req->data);
while (host->buffer_size > host->buffer_pos) {
t_val = readl(sock->addr + SOCK_MMCSD_DATA);
- host->buffer[host->buffer_pos++] = t_val & 0xff;
- host->buffer[host->buffer_pos++] =
+ 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 (host->buffer) {
+ } else if (no_dma) {
+ buffer = tifm_sd_kmap_atomic(host->req->data);
if ((cmd->data->flags & MMC_DATA_READ) &&
(host_status & TIFM_MMCSD_AF)) {
for (cnt = 0; cnt < TIFM_MMCSD_FIFO_SIZE; cnt++) {
t_val = readl(sock->addr + SOCK_MMCSD_DATA);
if (host->buffer_size > host->buffer_pos) {
- host->buffer[host->buffer_pos++] =
+ buffer[host->buffer_pos++] =
t_val & 0xff;
- host->buffer[host->buffer_pos++] =
+ buffer[host->buffer_pos++] =
(t_val >> 8) & 0xff;
}
}
@@ -142,14 +155,16 @@
&& (host_status & TIFM_MMCSD_AE)) {
for (cnt = 0; cnt < TIFM_MMCSD_FIFO_SIZE; cnt++) {
if (host->buffer_size > host->buffer_pos) {
- t_val = host->buffer[host->buffer_pos++] & 0x00ff;
- t_val |= ((host->buffer[host->buffer_pos++]) << 8)
- & 0xff00;
+ t_val = buffer[host->buffer_pos++]
+ & 0x00ff;
+ t_val |= ((buffer[host->buffer_pos++])
+ << 8) & 0xff00;
writel(t_val,
sock->addr + SOCK_MMCSD_DATA);
}
}
}
+ tifm_sd_kunmap_atomic(buffer, host->req->data);
}
return 0;
}
@@ -561,15 +576,6 @@
struct tifm_dev *sock = host->dev;
unsigned long flags;
struct mmc_data *r_data = mrq->cmd->data;
- char *t_buffer = NULL;
-
- if (r_data) {
- t_buffer = kmap(r_data->sg->page);
- if (!t_buffer) {
- printk(KERN_ERR DRIVER_NAME ": kmap failed\n");
- goto err_out;
- }
- }
spin_lock_irqsave(&sock->lock, flags);
if (host->flags & EJECT) {
@@ -586,7 +592,6 @@
if (r_data) {
tifm_sd_set_data_timeout(host, r_data);
- host->buffer = t_buffer + r_data->sg->offset;
host->buffer_size = mrq->cmd->data->blocks *
mrq->cmd->data->blksz;
@@ -615,9 +620,6 @@
return;
err_out:
- if (t_buffer)
- kunmap(r_data->sg->page);
-
mrq->cmd->error = MMC_ERR_TIMEOUT;
mmc_request_done(mmc, mrq);
}
@@ -659,7 +661,6 @@
r_data->bytes_xfered += r_data->blksz -
readl(sock->addr + SOCK_MMCSD_BLOCK_LEN) + 1;
}
- host->buffer = NULL;
host->buffer_pos = 0;
host->buffer_size = 0;
}
@@ -669,9 +670,6 @@
spin_unlock_irqrestore(&sock->lock, flags);
- if (r_data)
- kunmap(r_data->sg->page);
-
mmc_request_done(mmc, mrq);
}