[PATCH v1 0/7] xhci: mem: Short cleanup series

[PATCH v1 0/7] xhci: mem: Short cleanup series

[Andy Shevchenko]

Clean up xhci-mem.c a bit using latest and greatest Linux kernel
features.

Andy Shevchenko (7):
  xhci: mem: Carefully calculate size for memory allocations
  xhci: mem: Use __GFP_ZERO instead of explicit memset() call
  xhci: mem: Get rid of redundant 'else'
  xhci: mem: Drop useless return:s
  xhci: mem: Use while (i--) pattern to clean up
  xhci: mem: Replace explicit castings with appropriate specifiers
  xhci: mem: Join string literals back

 drivers/usb/host/xhci-mem.c | 85 +++++++++++++++----------------------
 1 file changed, 35 insertions(+), 50 deletions(-)

-- 
2.39.1

[PATCH v1 1/7] xhci: mem: Carefully calculate size for memory allocations

[Andy Shevchenko]

Carefully calculate size for memory allocations, i.e. with help
of size_mul() macro from overflow.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index d0a9467aa5fc..c385513ad00b 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -9,6 +9,7 @@
  */
 
 #include <linux/usb.h>
+#include <linux/overflow.h>
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/dmapool.h>
@@ -568,7 +569,7 @@ static struct xhci_stream_ctx *xhci_alloc_stream_ctx(struct xhci_hcd *xhci,
 		gfp_t mem_flags)
 {
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
-	size_t size = sizeof(struct xhci_stream_ctx) * num_stream_ctxs;
+	size_t size = size_mul(sizeof(struct xhci_stream_ctx), num_stream_ctxs);
 
 	if (size > MEDIUM_STREAM_ARRAY_SIZE)
 		return dma_alloc_coherent(dev, size,
@@ -1660,7 +1661,7 @@ static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
 		goto fail_sp;
 
 	xhci->scratchpad->sp_array = dma_alloc_coherent(dev,
-				     num_sp * sizeof(u64),
+				     size_mul(sizeof(u64), num_sp),
 				     &xhci->scratchpad->sp_dma, flags);
 	if (!xhci->scratchpad->sp_array)
 		goto fail_sp2;
@@ -1799,7 +1800,7 @@ int xhci_alloc_erst(struct xhci_hcd *xhci,
 	struct xhci_segment *seg;
 	struct xhci_erst_entry *entry;
 
-	size = sizeof(struct xhci_erst_entry) * evt_ring->num_segs;
+	size = size_mul(sizeof(struct xhci_erst_entry), evt_ring->num_segs);
 	erst->entries = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
 					   size, &erst->erst_dma_addr, flags);
 	if (!erst->entries)
@@ -1830,7 +1831,7 @@ xhci_free_interrupter(struct xhci_hcd *xhci, struct xhci_interrupter *ir)
 	if (!ir)
 		return;
 
-	erst_size = sizeof(struct xhci_erst_entry) * (ir->erst.num_entries);
+	erst_size = sizeof(struct xhci_erst_entry) * ir->erst.num_entries;
 	if (ir->erst.entries)
 		dma_free_coherent(dev, erst_size,
 				  ir->erst.entries,
-- 
2.39.1

[PATCH v1 2/7] xhci: mem: Use __GFP_ZERO instead of explicit memset() call

[Andy Shevchenko]

Use __GFP_ZERO instead of explicit memset() call in
xhci_alloc_stream_ctx().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index c385513ad00b..768adcb544a7 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -571,6 +571,8 @@ static struct xhci_stream_ctx *xhci_alloc_stream_ctx(struct xhci_hcd *xhci,
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
 	size_t size = size_mul(sizeof(struct xhci_stream_ctx), num_stream_ctxs);
 
+	mem_flags |= __GFP_ZERO;
+
 	if (size > MEDIUM_STREAM_ARRAY_SIZE)
 		return dma_alloc_coherent(dev, size,
 				dma, mem_flags);
@@ -643,8 +645,6 @@ struct xhci_stream_info *xhci_alloc_stream_info(struct xhci_hcd *xhci,
 			mem_flags);
 	if (!stream_info->stream_ctx_array)
 		goto cleanup_ring_array;
-	memset(stream_info->stream_ctx_array, 0,
-			sizeof(struct xhci_stream_ctx)*num_stream_ctxs);
 
 	/* Allocate everything needed to free the stream rings later */
 	stream_info->free_streams_command =
-- 
2.39.1

[PATCH v1 3/7] xhci: mem: Get rid of redundant 'else'

[Andy Shevchenko]

In the snippets like the following

	if (...)
		return / goto / break / continue ...;
	else
		...

the 'else' is redundant. Get rid of it.

While at it, make if chain sorted from testing bigger values to smaller.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 768adcb544a7..34f5ba19471e 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -574,14 +574,11 @@ static struct xhci_stream_ctx *xhci_alloc_stream_ctx(struct xhci_hcd *xhci,
 	mem_flags |= __GFP_ZERO;
 
 	if (size > MEDIUM_STREAM_ARRAY_SIZE)
-		return dma_alloc_coherent(dev, size,
-				dma, mem_flags);
-	else if (size <= SMALL_STREAM_ARRAY_SIZE)
-		return dma_pool_alloc(xhci->small_streams_pool,
-				mem_flags, dma);
+		return dma_alloc_coherent(dev, size, dma, mem_flags);
+	if (size > SMALL_STREAM_ARRAY_SIZE)
+		return dma_pool_alloc(xhci->medium_streams_pool, mem_flags, dma);
 	else
-		return dma_pool_alloc(xhci->medium_streams_pool,
-				mem_flags, dma);
+		return dma_pool_alloc(xhci->small_streams_pool, mem_flags, dma);
 }
 
 struct xhci_ring *xhci_dma_to_transfer_ring(
@@ -1401,8 +1398,9 @@ static u32 xhci_get_max_esit_payload(struct usb_device *udev,
 	if ((udev->speed >= USB_SPEED_SUPER_PLUS) &&
 	    USB_SS_SSP_ISOC_COMP(ep->ss_ep_comp.bmAttributes))
 		return le32_to_cpu(ep->ssp_isoc_ep_comp.dwBytesPerInterval);
+
 	/* SuperSpeed or SuperSpeedPlus Isoc ep with less than 48k per esit */
-	else if (udev->speed >= USB_SPEED_SUPER)
+	if (udev->speed >= USB_SPEED_SUPER)
 		return le16_to_cpu(ep->ss_ep_comp.wBytesPerInterval);
 
 	max_packet = usb_endpoint_maxp(&ep->desc);
-- 
2.39.1

[PATCH v1 4/7] xhci: mem: Drop useless return:s

[Andy Shevchenko]

When function returns void and we have if-else-if chain, there is
no need to explicitly call return. Drop them and indent lines better.

While at it, make if chain sorted from testing bigger values to smaller.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 34f5ba19471e..5c873e62c4d3 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -544,14 +544,11 @@ static void xhci_free_stream_ctx(struct xhci_hcd *xhci,
 	size_t size = sizeof(struct xhci_stream_ctx) * num_stream_ctxs;
 
 	if (size > MEDIUM_STREAM_ARRAY_SIZE)
-		dma_free_coherent(dev, size,
-				stream_ctx, dma);
-	else if (size <= SMALL_STREAM_ARRAY_SIZE)
-		return dma_pool_free(xhci->small_streams_pool,
-				stream_ctx, dma);
+		dma_free_coherent(dev, size, stream_ctx, dma);
+	else if (size > SMALL_STREAM_ARRAY_SIZE)
+		dma_pool_free(xhci->medium_streams_pool, stream_ctx, dma);
 	else
-		return dma_pool_free(xhci->medium_streams_pool,
-				stream_ctx, dma);
+		dma_pool_free(xhci->small_streams_pool, stream_ctx, dma);
 }
 
 /*
-- 
2.39.1

[PATCH v1 5/7] xhci: mem: Use while (i--) pattern to clean up

[Andy Shevchenko]

Use more natural while (i--) patter to clean up allocated resources.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 5c873e62c4d3..a3351b11efa5 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1681,11 +1681,10 @@ static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
 	return 0;
 
  fail_sp4:
-	for (i = i - 1; i >= 0; i--) {
+	while (i--)
 		dma_free_coherent(dev, xhci->page_size,
 				    xhci->scratchpad->sp_buffers[i],
 				    xhci->scratchpad->sp_array[i]);
-	}
 
 	kfree(xhci->scratchpad->sp_buffers);
 
-- 
2.39.1

[PATCH v1 6/7] xhci: mem: Replace explicit castings with appropriate specifiers

[Andy Shevchenko]

There is no need to have explicit castings when we have specific pointer extensions
Replace the explicit castings with appropriate specifiers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a3351b11efa5..fef74e7c20fc 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -668,8 +668,7 @@ struct xhci_stream_info *xhci_alloc_stream_info(struct xhci_hcd *xhci,
 			cur_ring->cycle_state;
 		stream_info->stream_ctx_array[cur_stream].stream_ring =
 			cpu_to_le64(addr);
-		xhci_dbg(xhci, "Setting stream %d ring ptr to 0x%08llx\n",
-				cur_stream, (unsigned long long) addr);
+		xhci_dbg(xhci, "Setting stream %d ring ptr to 0x%08llx\n", cur_stream, addr);
 
 		ret = xhci_update_stream_mapping(cur_ring, mem_flags);
 		if (ret) {
@@ -979,16 +978,14 @@ int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id,
 	if (!dev->out_ctx)
 		goto fail;
 
-	xhci_dbg(xhci, "Slot %d output ctx = 0x%llx (dma)\n", slot_id,
-			(unsigned long long)dev->out_ctx->dma);
+	xhci_dbg(xhci, "Slot %d output ctx = 0x%pad (dma)\n", slot_id, &dev->out_ctx->dma);
 
 	/* Allocate the (input) device context for address device command */
 	dev->in_ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_INPUT, flags);
 	if (!dev->in_ctx)
 		goto fail;
 
-	xhci_dbg(xhci, "Slot %d input ctx = 0x%llx (dma)\n", slot_id,
-			(unsigned long long)dev->in_ctx->dma);
+	xhci_dbg(xhci, "Slot %d input ctx = 0x%pad (dma)\n", slot_id, &dev->in_ctx->dma);
 
 	/* Initialize the cancellation and bandwidth list for each ep */
 	for (i = 0; i < 31; i++) {
@@ -2353,8 +2350,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 		goto fail;
 	xhci->dcbaa->dma = dma;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"// Device context base array address = 0x%llx (DMA), %p (virt)",
-			(unsigned long long)xhci->dcbaa->dma, xhci->dcbaa);
+			"// Device context base array address = 0x%pad (DMA), %p (virt)",
+			&xhci->dcbaa->dma, xhci->dcbaa);
 	xhci_write_64(xhci, dma, &xhci->op_regs->dcbaa_ptr);
 
 	/*
@@ -2395,8 +2392,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 		goto fail;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"Allocated command ring at %p", xhci->cmd_ring);
-	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "First segment DMA is 0x%llx",
-			(unsigned long long)xhci->cmd_ring->first_seg->dma);
+	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "First segment DMA is 0x%pad",
+			&xhci->cmd_ring->first_seg->dma);
 
 	/* Set the address in the Command Ring Control register */
 	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
-- 
2.39.1

[PATCH v1 7/7] xhci: mem: Join string literals back

[Andy Shevchenko]

For easy grepping on debug purposes join string literals back in
the messages.

No functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index fef74e7c20fc..9bdf2ed85772 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -609,8 +609,7 @@ struct xhci_stream_info *xhci_alloc_stream_info(struct xhci_hcd *xhci,
 	int ret;
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
 
-	xhci_dbg(xhci, "Allocating %u streams and %u "
-			"stream context array entries.\n",
+	xhci_dbg(xhci, "Allocating %u streams and %u stream context array entries.\n",
 			num_streams, num_stream_ctxs);
 	if (xhci->cmd_ring_reserved_trbs == MAX_RSVD_CMD_TRBS) {
 		xhci_dbg(xhci, "Command ring has no reserved TRBs available\n");
@@ -1952,8 +1951,7 @@ static void xhci_set_hc_event_deq(struct xhci_hcd *xhci, struct xhci_interrupter
 	deq = xhci_trb_virt_to_dma(ir->event_ring->deq_seg,
 			ir->event_ring->dequeue);
 	if (!deq)
-		xhci_warn(xhci, "WARN something wrong with SW event ring "
-				"dequeue ptr.\n");
+		xhci_warn(xhci, "WARN something wrong with SW event ring dequeue ptr.\n");
 	/* Update HC event ring dequeue pointer */
 	temp = xhci_read_64(xhci, &ir->ir_set->erst_dequeue);
 	temp &= ERST_PTR_MASK;
@@ -1962,8 +1960,7 @@ static void xhci_set_hc_event_deq(struct xhci_hcd *xhci, struct xhci_interrupter
 	 */
 	temp &= ~ERST_EHB;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"// Write event ring dequeue pointer, "
-			"preserving EHB bit");
+		       "// Write event ring dequeue pointer, preserving EHB bit");
 	xhci_write_64(xhci, ((u64) deq & (u64) ~ERST_PTR_MASK) | temp,
 			&ir->ir_set->erst_dequeue);
 }
@@ -1996,8 +1993,7 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 	} else if (major_revision <= 0x02) {
 		rhub = &xhci->usb2_rhub;
 	} else {
-		xhci_warn(xhci, "Ignoring unknown port speed, "
-				"Ext Cap %p, revision = 0x%x\n",
+		xhci_warn(xhci, "Ignoring unknown port speed, Ext Cap %p, revision = 0x%x\n",
 				addr, major_revision);
 		/* Ignoring port protocol we can't understand. FIXME */
 		return;
@@ -2012,9 +2008,8 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 	port_offset = XHCI_EXT_PORT_OFF(temp);
 	port_count = XHCI_EXT_PORT_COUNT(temp);
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"Ext Cap %p, port offset = %u, "
-			"count = %u, revision = 0x%x",
-			addr, port_offset, port_count, major_revision);
+		       "Ext Cap %p, port offset = %u, count = %u, revision = 0x%x",
+		       addr, port_offset, port_count, major_revision);
 	/* Port count includes the current port offset */
 	if (port_offset == 0 || (port_offset + port_count - 1) > num_ports)
 		/* WTF? "Valid values are ‘1’ to MaxPorts" */
@@ -2071,10 +2066,8 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 		struct xhci_port *hw_port = &xhci->hw_ports[i];
 		/* Duplicate entry.  Ignore the port if the revisions differ. */
 		if (hw_port->rhub) {
-			xhci_warn(xhci, "Duplicate port entry, Ext Cap %p,"
-					" port %u\n", addr, i);
-			xhci_warn(xhci, "Port was marked as USB %u, "
-					"duplicated as USB %u\n",
+			xhci_warn(xhci, "Duplicate port entry, Ext Cap %p, port %u\n", addr, i);
+			xhci_warn(xhci, "Port was marked as USB %u, duplicated as USB %u\n",
 					hw_port->rhub->maj_rev, major_revision);
 			/* Only adjust the roothub port counts if we haven't
 			 * found a similar duplicate.
@@ -2413,8 +2406,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	val = readl(&xhci->cap_regs->db_off);
 	val &= DBOFF_MASK;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"// Doorbell array is located at offset 0x%x"
-			" from cap regs base addr", val);
+		       "// Doorbell array is located at offset 0x%x from cap regs base addr",
+		       val);
 	xhci->dba = (void __iomem *) xhci->cap_regs + val;
 	/* Set ir_set to interrupt register set 0 */
 
-- 
2.39.1

Re: [PATCH v1 2/7] xhci: mem: Use __GFP_ZERO instead of explicit memset() call

[Mathias Nyman]

On 6.2.2023 18.10, Andy Shevchenko wrote:
> Use __GFP_ZERO instead of explicit memset() call in
> xhci_alloc_stream_ctx().
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>   drivers/usb/host/xhci-mem.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
> index c385513ad00b..768adcb544a7 100644
> --- a/drivers/usb/host/xhci-mem.c
> +++ b/drivers/usb/host/xhci-mem.c
> @@ -571,6 +571,8 @@ static struct xhci_stream_ctx *xhci_alloc_stream_ctx(struct xhci_hcd *xhci,
>   	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
>   	size_t size = size_mul(sizeof(struct xhci_stream_ctx), num_stream_ctxs);
>   
> +	mem_flags |= __GFP_ZERO;
> +

How about calling dma_pool_zalloc() instead of setting __GFP_ZERO flag?
Memory returned by dma_alloc_coherent() should already be zeroed if I remember correctly

-Mathias

Re: [PATCH v1 2/7] xhci: mem: Use __GFP_ZERO instead of explicit memset() call

[Andy Shevchenko]

On Tue, Feb 07, 2023 at 05:11:23PM +0200, Mathias Nyman wrote:
> On 6.2.2023 18.10, Andy Shevchenko wrote:
> > Use __GFP_ZERO instead of explicit memset() call in
> > xhci_alloc_stream_ctx().

...

> > +	mem_flags |= __GFP_ZERO;
> 
> How about calling dma_pool_zalloc() instead of setting __GFP_ZERO flag?
> Memory returned by dma_alloc_coherent() should already be zeroed if I remember correctly

That will work too.

-- 
With Best Regards,
Andy Shevchenko