diff mbox series

[05/11] mmc: s3cmci: handle highmem pages

Message ID 20190114095804.27978-6-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/11] mmc: davinci: handle highmem pages | expand

Commit Message

Christoph Hellwig Jan. 14, 2019, 9:57 a.m. UTC 
Instead of setting up a kernel pointer to track the current PIO address,
track the offset in the current page, and do an atomic kmap for the page
while doing the actual PIO operations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/mmc/host/s3cmci.c | 107 +++++++++++++++++++-------------------
 drivers/mmc/host/s3cmci.h |   3 +-
 2 files changed, 55 insertions(+), 55 deletions(-)

Comments

Ulf Hansson Jan. 30, 2019, 7:57 a.m. UTC | #1 
On Mon, 14 Jan 2019 at 10:58, Christoph Hellwig <hch@lst.de> wrote:
>
> Instead of setting up a kernel pointer to track the current PIO address,
> track the offset in the current page, and do an atomic kmap for the page
> while doing the actual PIO operations.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Nitpick: This one have some trailing whitespace errors, which git
complains about when I apply it.

No need to re-spin due to this, I can fix it  up.

Kind regards
Uffe

> ---
>  drivers/mmc/host/s3cmci.c | 107 +++++++++++++++++++-------------------
>  drivers/mmc/host/s3cmci.h |   3 +-
>  2 files changed, 55 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c
> index 10f5219b3b40..1be84426c817 100644
> --- a/drivers/mmc/host/s3cmci.c
> +++ b/drivers/mmc/host/s3cmci.c
> @@ -15,6 +15,7 @@
>  #include <linux/dmaengine.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/clk.h>
> +#include <linux/highmem.h>
>  #include <linux/mmc/host.h>
>  #include <linux/platform_device.h>
>  #include <linux/cpufreq.h>
> @@ -317,26 +318,17 @@ static void s3cmci_check_sdio_irq(struct s3cmci_host *host)
>         }
>  }
>
> -static inline int get_data_buffer(struct s3cmci_host *host,
> -                                 u32 *bytes, u32 **pointer)
> +static inline int get_data_buffer(struct s3cmci_host *host)
>  {
> -       struct scatterlist *sg;
> -
> -       if (host->pio_active == XFER_NONE)
> -               return -EINVAL;
> -
> -       if ((!host->mrq) || (!host->mrq->data))
> -               return -EINVAL;
> -
>         if (host->pio_sgptr >= host->mrq->data->sg_len) {
>                 dbg(host, dbg_debug, "no more buffers (%i/%i)\n",
>                       host->pio_sgptr, host->mrq->data->sg_len);
>                 return -EBUSY;
>         }
> -       sg = &host->mrq->data->sg[host->pio_sgptr];
> +       host->cur_sg = &host->mrq->data->sg[host->pio_sgptr];
>
> -       *bytes = sg->length;
> -       *pointer = sg_virt(sg);
> +       host->pio_bytes = host->cur_sg->length;
> +       host->pio_offset = host->cur_sg->offset;
>
>         host->pio_sgptr++;
>
> @@ -422,11 +414,16 @@ static void s3cmci_disable_irq(struct s3cmci_host *host, bool transfer)
>
>  static void do_pio_read(struct s3cmci_host *host)
>  {
> -       int res;
>         u32 fifo;
>         u32 *ptr;
>         u32 fifo_words;
>         void __iomem *from_ptr;
> +       void *buf;
> +
> +       if (host->pio_active == XFER_NONE)
> +               goto done;
> +       if (!host->mrq || !host->mrq->data)
> +               goto done;
>
>         /* write real prescaler to host, it might be set slow to fix */
>         writel(host->prescaler, host->base + S3C2410_SDIPRE);
> @@ -435,20 +432,12 @@ static void do_pio_read(struct s3cmci_host *host)
>
>         while ((fifo = fifo_count(host))) {
>                 if (!host->pio_bytes) {
> -                       res = get_data_buffer(host, &host->pio_bytes,
> -                                             &host->pio_ptr);
> -                       if (res) {
> -                               host->pio_active = XFER_NONE;
> -                               host->complete_what = COMPLETION_FINALIZE;
> -
> -                               dbg(host, dbg_pio, "pio_read(): "
> -                                   "complete (no more data).\n");
> -                               return;
> -                       }
> +                       if (get_data_buffer(host) < 0)
> +                               goto done;
>
>                         dbg(host, dbg_pio,
> -                           "pio_read(): new target: [%i]@[%p]\n",
> -                           host->pio_bytes, host->pio_ptr);
> +                           "pio_read(): new target: [%i]@[%zu]\n",
> +                           host->pio_bytes, host->pio_offset);
>                 }
>
>                 dbg(host, dbg_pio,
> @@ -470,63 +459,65 @@ static void do_pio_read(struct s3cmci_host *host)
>                 host->pio_count += fifo;
>
>                 fifo_words = fifo >> 2;
> -               ptr = host->pio_ptr;
> -               while (fifo_words--)
> +
> +               buf = (kmap_atomic(sg_page(host->cur_sg)) + host->pio_offset);
> +               ptr = buf;
> +               while (fifo_words--) {
>                         *ptr++ = readl(from_ptr);
> -               host->pio_ptr = ptr;
> +                       host->pio_offset += 4;
> +               }
>
>                 if (fifo & 3) {
>                         u32 n = fifo & 3;
>                         u32 data = readl(from_ptr);
> -                       u8 *p = (u8 *)host->pio_ptr;
> +                       u8 *p = (u8 *)ptr;
>
>                         while (n--) {
>                                 *p++ = data;
>                                 data >>= 8;
> +                               host->pio_offset++;
>                         }
>                 }
> +               kunmap_atomic(buf);
>         }
>
>         if (!host->pio_bytes) {
> -               res = get_data_buffer(host, &host->pio_bytes, &host->pio_ptr);
> -               if (res) {
> -                       dbg(host, dbg_pio,
> -                           "pio_read(): complete (no more buffers).\n");
> -                       host->pio_active = XFER_NONE;
> -                       host->complete_what = COMPLETION_FINALIZE;
> -
> -                       return;
> -               }
> +               if (get_data_buffer(host) < 0)
> +                       goto done;
>         }
>
>         enable_imask(host,
>                      S3C2410_SDIIMSK_RXFIFOHALF | S3C2410_SDIIMSK_RXFIFOLAST);
> +       return;
> +
> +done:
> +       host->pio_active = XFER_NONE;
> +       host->complete_what = COMPLETION_FINALIZE;
> +       dbg(host, dbg_pio, "pio_read(): complete (no more data).\n");
>  }
>
>  static void do_pio_write(struct s3cmci_host *host)
>  {
>         void __iomem *to_ptr;
> -       int res;
> +       void *buf;
>         u32 fifo;
>         u32 *ptr;
>
> +       if (host->pio_active == XFER_NONE)
> +               goto done;
> +       if (!host->mrq || !host->mrq->data)
> +               goto done;
> +
>         to_ptr = host->base + host->sdidata;
>
>         while ((fifo = fifo_free(host)) > 3) {
>                 if (!host->pio_bytes) {
> -                       res = get_data_buffer(host, &host->pio_bytes,
> -                                                       &host->pio_ptr);
> -                       if (res) {
> -                               dbg(host, dbg_pio,
> -                                   "pio_write(): complete (no more data).\n");
> -                               host->pio_active = XFER_NONE;
> -
> -                               return;
> -                       }
> +                       if (get_data_buffer(host) < 0)
> +                               goto done;
>
>                         dbg(host, dbg_pio,
> -                           "pio_write(): new source: [%i]@[%p]\n",
> -                           host->pio_bytes, host->pio_ptr);
> +                           "pio_write(): new source: [%i]@[%zd]\n",
> +                           host->pio_bytes, host->pio_offset);
>
>                 }
>
> @@ -543,13 +534,20 @@ static void do_pio_write(struct s3cmci_host *host)
>                 host->pio_count += fifo;
>
>                 fifo = (fifo + 3) >> 2;
> -               ptr = host->pio_ptr;
> -               while (fifo--)
> +               buf = (kmap_atomic(sg_page(host->cur_sg)) + host->pio_offset);
> +               ptr = buf;
> +               while (fifo--) {
>                         writel(*ptr++, to_ptr);
> -               host->pio_ptr = ptr;
> +                       host->pio_offset += 4;
> +               }
> +               kunmap_atomic(buf);
>         }
>
>         enable_imask(host, S3C2410_SDIIMSK_TXFIFOHALF);
> +       return;
> +done:
> +       dbg(host, dbg_pio, "pio_write(): complete (no more data).\n");
> +       host->pio_active = XFER_NONE;
>  }
>
>  static void pio_tasklet(unsigned long data)
> @@ -1055,6 +1053,7 @@ static int s3cmci_prepare_pio(struct s3cmci_host *host, struct mmc_data *data)
>         BUG_ON((data->flags & BOTH_DIR) == BOTH_DIR);
>
>         host->pio_sgptr = 0;
> +       host->cur_sg = &host->mrq->data->sg[host->pio_sgptr];
>         host->pio_bytes = 0;
>         host->pio_count = 0;
>         host->pio_active = rw ? XFER_WRITE : XFER_READ;
> diff --git a/drivers/mmc/host/s3cmci.h b/drivers/mmc/host/s3cmci.h
> index 30c2c0dd1bc8..4320f7d832dc 100644
> --- a/drivers/mmc/host/s3cmci.h
> +++ b/drivers/mmc/host/s3cmci.h
> @@ -50,10 +50,11 @@ struct s3cmci_host {
>
>         int                     dma_complete;
>
> +       struct scatterlist      *cur_sg;
>         u32                     pio_sgptr;
>         u32                     pio_bytes;
>         u32                     pio_count;
> -       u32                     *pio_ptr;
> +       u32                     pio_offset;
>  #define XFER_NONE 0
>  #define XFER_READ 1
>  #define XFER_WRITE 2
> --
> 2.20.1
>
Christoph Hellwig Jan. 30, 2019, 8:04 a.m. UTC | #2 
On Wed, Jan 30, 2019 at 08:57:47AM +0100, Ulf Hansson wrote:
> On Mon, 14 Jan 2019 at 10:58, Christoph Hellwig <hch@lst.de> wrote:
> >
> > Instead of setting up a kernel pointer to track the current PIO address,
> > track the offset in the current page, and do an atomic kmap for the page
> > while doing the actual PIO operations.
> >
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> 
> Nitpick: This one have some trailing whitespace errors, which git
> complains about when I apply it.
> 
> No need to re-spin due to this, I can fix it  up.

I'll need to respin to limit the segment size to a page anyway, so I
will take this into account as well for v2.
Ulf Hansson Jan. 30, 2019, 8:16 a.m. UTC | #3 
On Wed, 30 Jan 2019 at 09:04, Christoph Hellwig <hch@lst.de> wrote:
>
> On Wed, Jan 30, 2019 at 08:57:47AM +0100, Ulf Hansson wrote:
> > On Mon, 14 Jan 2019 at 10:58, Christoph Hellwig <hch@lst.de> wrote:
> > >
> > > Instead of setting up a kernel pointer to track the current PIO address,
> > > track the offset in the current page, and do an atomic kmap for the page
> > > while doing the actual PIO operations.
> > >
> > > Signed-off-by: Christoph Hellwig <hch@lst.de>
> >
> > Nitpick: This one have some trailing whitespace errors, which git
> > complains about when I apply it.
> >
> > No need to re-spin due to this, I can fix it  up.
>
> I'll need to respin to limit the segment size to a page anyway, so I
> will take this into account as well for v2.

Okay!

FYI, I have no further comment on the series, it looks okay to me!

Kind regards
Uffe
diff mbox series

Patch

diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c
index 10f5219b3b40..1be84426c817 100644
--- a/drivers/mmc/host/s3cmci.c
+++ b/drivers/mmc/host/s3cmci.c
@@ -15,6 +15,7 @@ 
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/clk.h>
+#include <linux/highmem.h>
 #include <linux/mmc/host.h>
 #include <linux/platform_device.h>
 #include <linux/cpufreq.h>
@@ -317,26 +318,17 @@  static void s3cmci_check_sdio_irq(struct s3cmci_host *host)
 	}
 }
 
-static inline int get_data_buffer(struct s3cmci_host *host,
-				  u32 *bytes, u32 **pointer)
+static inline int get_data_buffer(struct s3cmci_host *host)
 {
-	struct scatterlist *sg;
-
-	if (host->pio_active == XFER_NONE)
-		return -EINVAL;
-
-	if ((!host->mrq) || (!host->mrq->data))
-		return -EINVAL;
-
 	if (host->pio_sgptr >= host->mrq->data->sg_len) {
 		dbg(host, dbg_debug, "no more buffers (%i/%i)\n",
 		      host->pio_sgptr, host->mrq->data->sg_len);
 		return -EBUSY;
 	}
-	sg = &host->mrq->data->sg[host->pio_sgptr];
+	host->cur_sg = &host->mrq->data->sg[host->pio_sgptr];
 
-	*bytes = sg->length;
-	*pointer = sg_virt(sg);
+	host->pio_bytes = host->cur_sg->length;
+	host->pio_offset = host->cur_sg->offset;
 
 	host->pio_sgptr++;
 
@@ -422,11 +414,16 @@  static void s3cmci_disable_irq(struct s3cmci_host *host, bool transfer)
 
 static void do_pio_read(struct s3cmci_host *host)
 {
-	int res;
 	u32 fifo;
 	u32 *ptr;
 	u32 fifo_words;
 	void __iomem *from_ptr;
+	void *buf;
+
+	if (host->pio_active == XFER_NONE)
+		goto done;
+	if (!host->mrq || !host->mrq->data)
+		goto done;
 
 	/* write real prescaler to host, it might be set slow to fix */
 	writel(host->prescaler, host->base + S3C2410_SDIPRE);
@@ -435,20 +432,12 @@  static void do_pio_read(struct s3cmci_host *host)
 
 	while ((fifo = fifo_count(host))) {
 		if (!host->pio_bytes) {
-			res = get_data_buffer(host, &host->pio_bytes,
-					      &host->pio_ptr);
-			if (res) {
-				host->pio_active = XFER_NONE;
-				host->complete_what = COMPLETION_FINALIZE;
-
-				dbg(host, dbg_pio, "pio_read(): "
-				    "complete (no more data).\n");
-				return;
-			}
+			if (get_data_buffer(host) < 0)
+				goto done;
 
 			dbg(host, dbg_pio,
-			    "pio_read(): new target: [%i]@[%p]\n",
-			    host->pio_bytes, host->pio_ptr);
+			    "pio_read(): new target: [%i]@[%zu]\n",
+			    host->pio_bytes, host->pio_offset);
 		}
 
 		dbg(host, dbg_pio,
@@ -470,63 +459,65 @@  static void do_pio_read(struct s3cmci_host *host)
 		host->pio_count += fifo;
 
 		fifo_words = fifo >> 2;
-		ptr = host->pio_ptr;
-		while (fifo_words--)
+	
+		buf = (kmap_atomic(sg_page(host->cur_sg)) + host->pio_offset);
+		ptr = buf;
+		while (fifo_words--) {
 			*ptr++ = readl(from_ptr);
-		host->pio_ptr = ptr;
+			host->pio_offset += 4;
+		}
 
 		if (fifo & 3) {
 			u32 n = fifo & 3;
 			u32 data = readl(from_ptr);
-			u8 *p = (u8 *)host->pio_ptr;
+			u8 *p = (u8 *)ptr;
 
 			while (n--) {
 				*p++ = data;
 				data >>= 8;
+				host->pio_offset++;
 			}
 		}
+		kunmap_atomic(buf);
 	}
 
 	if (!host->pio_bytes) {
-		res = get_data_buffer(host, &host->pio_bytes, &host->pio_ptr);
-		if (res) {
-			dbg(host, dbg_pio,
-			    "pio_read(): complete (no more buffers).\n");
-			host->pio_active = XFER_NONE;
-			host->complete_what = COMPLETION_FINALIZE;
-
-			return;
-		}
+		if (get_data_buffer(host) < 0)
+			goto done;
 	}
 
 	enable_imask(host,
 		     S3C2410_SDIIMSK_RXFIFOHALF | S3C2410_SDIIMSK_RXFIFOLAST);
+	return;
+
+done:
+	host->pio_active = XFER_NONE;
+	host->complete_what = COMPLETION_FINALIZE;
+	dbg(host, dbg_pio, "pio_read(): complete (no more data).\n");
 }
 
 static void do_pio_write(struct s3cmci_host *host)
 {
 	void __iomem *to_ptr;
-	int res;
+	void *buf;
 	u32 fifo;
 	u32 *ptr;
 
+	if (host->pio_active == XFER_NONE)
+		goto done;
+	if (!host->mrq || !host->mrq->data)
+		goto done;
+
 	to_ptr = host->base + host->sdidata;
 
 	while ((fifo = fifo_free(host)) > 3) {
 		if (!host->pio_bytes) {
-			res = get_data_buffer(host, &host->pio_bytes,
-							&host->pio_ptr);
-			if (res) {
-				dbg(host, dbg_pio,
-				    "pio_write(): complete (no more data).\n");
-				host->pio_active = XFER_NONE;
-
-				return;
-			}
+			if (get_data_buffer(host) < 0)
+				goto done;
 
 			dbg(host, dbg_pio,
-			    "pio_write(): new source: [%i]@[%p]\n",
-			    host->pio_bytes, host->pio_ptr);
+			    "pio_write(): new source: [%i]@[%zd]\n",
+			    host->pio_bytes, host->pio_offset);
 
 		}
 
@@ -543,13 +534,20 @@  static void do_pio_write(struct s3cmci_host *host)
 		host->pio_count += fifo;
 
 		fifo = (fifo + 3) >> 2;
-		ptr = host->pio_ptr;
-		while (fifo--)
+		buf = (kmap_atomic(sg_page(host->cur_sg)) + host->pio_offset);
+		ptr = buf;
+		while (fifo--) {
 			writel(*ptr++, to_ptr);
-		host->pio_ptr = ptr;
+			host->pio_offset += 4;
+		}
+		kunmap_atomic(buf);
 	}
 
 	enable_imask(host, S3C2410_SDIIMSK_TXFIFOHALF);
+	return;
+done:
+	dbg(host, dbg_pio, "pio_write(): complete (no more data).\n");
+	host->pio_active = XFER_NONE;
 }
 
 static void pio_tasklet(unsigned long data)
@@ -1055,6 +1053,7 @@  static int s3cmci_prepare_pio(struct s3cmci_host *host, struct mmc_data *data)
 	BUG_ON((data->flags & BOTH_DIR) == BOTH_DIR);
 
 	host->pio_sgptr = 0;
+	host->cur_sg = &host->mrq->data->sg[host->pio_sgptr];
 	host->pio_bytes = 0;
 	host->pio_count = 0;
 	host->pio_active = rw ? XFER_WRITE : XFER_READ;
diff --git a/drivers/mmc/host/s3cmci.h b/drivers/mmc/host/s3cmci.h
index 30c2c0dd1bc8..4320f7d832dc 100644
--- a/drivers/mmc/host/s3cmci.h
+++ b/drivers/mmc/host/s3cmci.h
@@ -50,10 +50,11 @@  struct s3cmci_host {
 
 	int			dma_complete;
 
+	struct scatterlist	*cur_sg;
 	u32			pio_sgptr;
 	u32			pio_bytes;
 	u32			pio_count;
-	u32			*pio_ptr;
+	u32			pio_offset;
 #define XFER_NONE 0
 #define XFER_READ 1
 #define XFER_WRITE 2