[RFC PATCH 2/8] openrisc: mm: remove unneeded early ioremap code

[RFC PATCH 2/8] openrisc: mm: remove unneeded early ioremap code

[Christophe Leroy]

From: Baoquan He <bhe@redhat.com>

Under arch/openrisc, there isn't any place where ioremap() is called.
It means that there isn't early ioremap handling needed in openrisc,
So the early ioremap handling code in ioremap() of
arch/openrisc/mm/ioremap.c is unnecessary and can be removed.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: openrisc@lists.librecores.org
---
 arch/openrisc/mm/ioremap.c | 22 +++++-----------------
 1 file changed, 5 insertions(+), 17 deletions(-)

diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
index 8ec0dafecf25..90b59bc53c8c 100644
--- a/arch/openrisc/mm/ioremap.c
+++ b/arch/openrisc/mm/ioremap.c
@@ -22,8 +22,6 @@
 
 extern int mem_init_done;
 
-static unsigned int fixmaps_used __initdata;
-
 /*
  * Remap an arbitrary physical address space into the kernel virtual
  * address space. Needed when the kernel wants to access high addresses
@@ -52,24 +50,14 @@ void __iomem *__ref ioremap(phys_addr_t addr, unsigned long size)
 	p = addr & PAGE_MASK;
 	size = PAGE_ALIGN(last_addr + 1) - p;
 
-	if (likely(mem_init_done)) {
-		area = get_vm_area(size, VM_IOREMAP);
-		if (!area)
-			return NULL;
-		v = (unsigned long)area->addr;
-	} else {
-		if ((fixmaps_used + (size >> PAGE_SHIFT)) > FIX_N_IOREMAPS)
-			return NULL;
-		v = fix_to_virt(FIX_IOREMAP_BEGIN + fixmaps_used);
-		fixmaps_used += (size >> PAGE_SHIFT);
-	}
+	area = get_vm_area(size, VM_IOREMAP);
+	if (!area)
+		return NULL;
+	v = (unsigned long)area->addr;
 
 	if (ioremap_page_range(v, v + size, p,
 			__pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_CI))) {
-		if (likely(mem_init_done))
-			vfree(area->addr);
-		else
-			fixmaps_used -= (size >> PAGE_SHIFT);
+		vfree(area->addr);
 		return NULL;
 	}
 
-- 
2.37.1

Re: [RFC PATCH 2/8] openrisc: mm: remove unneeded early ioremap code

[Stafford Horne]

On Wed, Oct 12, 2022 at 12:09:38PM +0200, Christophe Leroy wrote:
> From: Baoquan He <bhe@redhat.com>
> 
> Under arch/openrisc, there isn't any place where ioremap() is called.
> It means that there isn't early ioremap handling needed in openrisc,
> So the early ioremap handling code in ioremap() of
> arch/openrisc/mm/ioremap.c is unnecessary and can be removed.
> 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Jonas Bonn <jonas@southpole.se>
> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> Cc: Stafford Horne <shorne@gmail.com>
> Cc: openrisc@lists.librecores.org

Thanks for picking this up.

Perhaps add this link?

Link: https://lore.kernel.org/linux-mm/YwxfxKrTUtAuejKQ@oscomms1/

But either way.

Acked-by: Stafford Horne <shorne@gmail.com>

> ---
>  arch/openrisc/mm/ioremap.c | 22 +++++-----------------
>  1 file changed, 5 insertions(+), 17 deletions(-)
> 
> diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
> index 8ec0dafecf25..90b59bc53c8c 100644
> --- a/arch/openrisc/mm/ioremap.c
> +++ b/arch/openrisc/mm/ioremap.c
> @@ -22,8 +22,6 @@
>  
>  extern int mem_init_done;
>  
> -static unsigned int fixmaps_used __initdata;
> -
>  /*
>   * Remap an arbitrary physical address space into the kernel virtual
>   * address space. Needed when the kernel wants to access high addresses
> @@ -52,24 +50,14 @@ void __iomem *__ref ioremap(phys_addr_t addr, unsigned long size)
>  	p = addr & PAGE_MASK;
>  	size = PAGE_ALIGN(last_addr + 1) - p;
>  
> -	if (likely(mem_init_done)) {
> -		area = get_vm_area(size, VM_IOREMAP);
> -		if (!area)
> -			return NULL;
> -		v = (unsigned long)area->addr;
> -	} else {
> -		if ((fixmaps_used + (size >> PAGE_SHIFT)) > FIX_N_IOREMAPS)
> -			return NULL;
> -		v = fix_to_virt(FIX_IOREMAP_BEGIN + fixmaps_used);
> -		fixmaps_used += (size >> PAGE_SHIFT);
> -	}
> +	area = get_vm_area(size, VM_IOREMAP);
> +	if (!area)
> +		return NULL;
> +	v = (unsigned long)area->addr;
>  
>  	if (ioremap_page_range(v, v + size, p,
>  			__pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_CI))) {
> -		if (likely(mem_init_done))
> -			vfree(area->addr);
> -		else
> -			fixmaps_used -= (size >> PAGE_SHIFT);
> +		vfree(area->addr);
>  		return NULL;
>  	}
>  
> -- 
> 2.37.1
>