diff mbox series

[02/19] PCI: endpoint: Improve pci_epc_mem_alloc_addr()

Message ID 20240329090945.1097609-3-dlemoal@kernel.org (mailing list archive)
State New, archived
Headers show
Series Improve PCI memory mapping API | expand

Commit Message

Damien Le Moal March 29, 2024, 9:09 a.m. UTC
There is no point in attempting to allocate memory from an endpoint
controller memory window if the requested size is larger than the window
size. Add a check to skip bitmap_find_free_region() calls for such case.
Also change the final return to return NULL to simplify the code.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/pci/endpoint/pci-epc-mem.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Frank Li March 29, 2024, 3:32 p.m. UTC | #1
On Fri, Mar 29, 2024 at 06:09:28PM +0900, Damien Le Moal wrote:
> There is no point in attempting to allocate memory from an endpoint
> controller memory window if the requested size is larger than the window
> size. Add a check to skip bitmap_find_free_region() calls for such case.
> Also change the final return to return NULL to simplify the code.
> 
> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
> ---
>  drivers/pci/endpoint/pci-epc-mem.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
> index a9c028f58da1..218a60e945db 100644
> --- a/drivers/pci/endpoint/pci-epc-mem.c
> +++ b/drivers/pci/endpoint/pci-epc-mem.c
> @@ -178,7 +178,7 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_exit);
>  void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
>  				     phys_addr_t *phys_addr, size_t size)

Mani is working to change alloc to genalloc:

https://lore.kernel.org/linux-pci/20240317-pci-ep-genalloc-v1-1-70fe52a3b9be@linaro.org/

Could you please wait it?

Frank

>  {
> -	void __iomem *virt_addr = NULL;
> +	void __iomem *virt_addr;
>  	struct pci_epc_mem *mem;
>  	unsigned int page_shift;
>  	size_t align_size;
> @@ -188,10 +188,13 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
>  
>  	for (i = 0; i < epc->num_windows; i++) {
>  		mem = epc->windows[i];
> -		mutex_lock(&mem->lock);
> +		if (size > mem->window.size)
> +			continue;
> +
>  		align_size = ALIGN(size, mem->window.page_size);
>  		order = pci_epc_mem_get_order(mem, align_size);
>  
> +		mutex_lock(&mem->lock);
>  		pageno = bitmap_find_free_region(mem->bitmap, mem->pages,
>  						 order);
>  		if (pageno >= 0) {
> @@ -211,7 +214,7 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
>  		mutex_unlock(&mem->lock);
>  	}
>  
> -	return virt_addr;
> +	return NULL;
>  }
>  EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
>  
> -- 
> 2.44.0
>
diff mbox series

Patch

diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
index a9c028f58da1..218a60e945db 100644
--- a/drivers/pci/endpoint/pci-epc-mem.c
+++ b/drivers/pci/endpoint/pci-epc-mem.c
@@ -178,7 +178,7 @@  EXPORT_SYMBOL_GPL(pci_epc_mem_exit);
 void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
 				     phys_addr_t *phys_addr, size_t size)
 {
-	void __iomem *virt_addr = NULL;
+	void __iomem *virt_addr;
 	struct pci_epc_mem *mem;
 	unsigned int page_shift;
 	size_t align_size;
@@ -188,10 +188,13 @@  void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
 
 	for (i = 0; i < epc->num_windows; i++) {
 		mem = epc->windows[i];
-		mutex_lock(&mem->lock);
+		if (size > mem->window.size)
+			continue;
+
 		align_size = ALIGN(size, mem->window.page_size);
 		order = pci_epc_mem_get_order(mem, align_size);
 
+		mutex_lock(&mem->lock);
 		pageno = bitmap_find_free_region(mem->bitmap, mem->pages,
 						 order);
 		if (pageno >= 0) {
@@ -211,7 +214,7 @@  void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
 		mutex_unlock(&mem->lock);
 	}
 
-	return virt_addr;
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);