diff mbox series

[11/14] mmc: tmio_mmc_core: Remove local_irq_{save,restore}() around k[un]map_atomic()

Message ID 20221005101951.3165-12-adrian.hunter@intel.com
State New
Headers show
Series [01/14] mmc: sdhci: Remove local_irq_{save,restore}() around k[un]map_atomic() | expand

Commit Message

Adrian Hunter Oct. 5, 2022, 10:19 a.m. UTC 
A long time ago the kmap_atomic API required a slot to be provided which
risked the possibility that other code might use the same slot at the
same time. Disabling interrupts prevented the possibility of an interrupt
handler doing that. However, that went away with
commit 3e4d3af501cc ("mm: stack based kmap_atomic()").

When the second argument to kmap_atomic was removed by commit 482fce997e14
("mmc: remove the second argument of k[un]map_atomic()"),
local_irq_{save,restore}() should have been removed also.

Remove it now.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/host/renesas_sdhi_sys_dmac.c |  5 ++---
 drivers/mmc/host/tmio_mmc.h              |  7 ++-----
 drivers/mmc/host/tmio_mmc_core.c         | 10 ++++------
 3 files changed, 8 insertions(+), 14 deletions(-)

Comments

Wolfram Sang Oct. 31, 2022, 7:36 p.m. UTC | #1 
On Wed, Oct 05, 2022 at 01:19:48PM +0300, Adrian Hunter wrote:
> A long time ago the kmap_atomic API required a slot to be provided which
> risked the possibility that other code might use the same slot at the
> same time. Disabling interrupts prevented the possibility of an interrupt
> handler doing that. However, that went away with
> commit 3e4d3af501cc ("mm: stack based kmap_atomic()").
> 
> When the second argument to kmap_atomic was removed by commit 482fce997e14
> ("mmc: remove the second argument of k[un]map_atomic()"),
> local_irq_{save,restore}() should have been removed also.
> 
> Remove it now.
> 
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Thank you for cleaning this cruft! Looks good.

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

I should be able to set up a board for testing this week as well.
Wolfram Sang Nov. 2, 2022, 12:06 p.m. UTC | #2 
Okay, testing turned out to be not so easy because injecting working
non-aligned buffers seems not as trivial as I thought and would require
more time than I can afford for these old systems. Some light testing
did work, though, but this is not enough for a Tested-by tag. The Rev-by
tags still stand, of course.
diff mbox series

Patch

diff --git a/drivers/mmc/host/renesas_sdhi_sys_dmac.c b/drivers/mmc/host/renesas_sdhi_sys_dmac.c
index 99e3426df702..e9cc6c15d229 100644
--- a/drivers/mmc/host/renesas_sdhi_sys_dmac.c
+++ b/drivers/mmc/host/renesas_sdhi_sys_dmac.c
@@ -254,12 +254,11 @@  static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
 
 	/* The only sg element can be unaligned, use our bounce buffer then */
 	if (!aligned) {
-		unsigned long flags;
-		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg);
 
 		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
 		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
-		tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
+		tmio_mmc_kunmap_atomic(sg, sg_vaddr);
 		host->sg_ptr = &host->bounce_sg;
 		sg = host->sg_ptr;
 	}
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
index 501613c74406..22375790b57b 100644
--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -204,18 +204,15 @@  void tmio_mmc_enable_mmc_irqs(struct tmio_mmc_host *host, u32 i);
 void tmio_mmc_disable_mmc_irqs(struct tmio_mmc_host *host, u32 i);
 irqreturn_t tmio_mmc_irq(int irq, void *devid);
 
-static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
-					 unsigned long *flags)
+static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg)
 {
-	local_irq_save(*flags);
 	return kmap_atomic(sg_page(sg)) + sg->offset;
 }
 
 static inline void tmio_mmc_kunmap_atomic(struct scatterlist *sg,
-					  unsigned long *flags, void *virt)
+					  void *virt)
 {
 	kunmap_atomic(virt - sg->offset);
-	local_irq_restore(*flags);
 }
 
 #ifdef CONFIG_PM
diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
index 437048bb8027..6d50c0dd53fe 100644
--- a/drivers/mmc/host/tmio_mmc_core.c
+++ b/drivers/mmc/host/tmio_mmc_core.c
@@ -412,7 +412,6 @@  static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 	void *sg_virt;
 	unsigned short *buf;
 	unsigned int count;
-	unsigned long flags;
 
 	if (host->dma_on) {
 		pr_err("PIO IRQ in DMA mode!\n");
@@ -422,7 +421,7 @@  static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 		return;
 	}
 
-	sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr, &flags);
+	sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr);
 	buf = (unsigned short *)(sg_virt + host->sg_off);
 
 	count = host->sg_ptr->length - host->sg_off;
@@ -437,7 +436,7 @@  static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 
 	host->sg_off += count;
 
-	tmio_mmc_kunmap_atomic(host->sg_ptr, &flags, sg_virt);
+	tmio_mmc_kunmap_atomic(host->sg_ptr, sg_virt);
 
 	if (host->sg_off == host->sg_ptr->length)
 		tmio_mmc_next_sg(host);
@@ -446,11 +445,10 @@  static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 static void tmio_mmc_check_bounce_buffer(struct tmio_mmc_host *host)
 {
 	if (host->sg_ptr == &host->bounce_sg) {
-		unsigned long flags;
-		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig);
 
 		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
-		tmio_mmc_kunmap_atomic(host->sg_orig, &flags, sg_vaddr);
+		tmio_mmc_kunmap_atomic(host->sg_orig, sg_vaddr);
 	}
 }