subject:"\[PATCH 11\/12\] kexec\: allow architectures to override boot mapping"

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

2016-05-12 Thread Russell King - ARM Linux

On Thu, May 12, 2016 at 02:26:27PM +0800, Baoquan He wrote:
> On 04/28/16 at 10:28am, Russell King wrote:
> > diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> > index 52a3a221bcb2..99cb9dac7909 100644
> > --- a/include/linux/kexec.h
> > +++ b/include/linux/kexec.h
> > @@ -318,6 +318,44 @@ int __weak arch_kexec_apply_relocations_add(const 
> > Elf_Ehdr *ehdr,
> >  int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr 
> > *sechdrs,
> > unsigned int relsec);
> >  
> > +#ifndef page_to_boot_pfn
> > +static inline unsigned long page_to_boot_pfn(struct page *page)
> > +{
> > +   return page_to_pfn(page);
> > +}
> > +#endif
> 
> I am thinking if it's appropriate to introduce a new concept which only
> exists in a certain system of a certain ARCH. Is it unavoidable? If have
> to can we name it as kexec_page_to_pfn/kexec_pfn_to_page, etc? People
> might not need to know about boot view physical address and kernel view
> physical address things when they just want to understand kexec
> implementation related to one ARCH except of ARM, even related to ARM
> but not Keystone 2.

Well, what do you suggest we do instead?

Eric, please get involved in this discussion, as this was your idea.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

2016-05-12 Thread Baoquan He

On 04/28/16 at 10:28am, Russell King wrote:
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 52a3a221bcb2..99cb9dac7909 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -318,6 +318,44 @@ int __weak arch_kexec_apply_relocations_add(const 
> Elf_Ehdr *ehdr,
>  int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr 
> *sechdrs,
>   unsigned int relsec);
>  
> +#ifndef page_to_boot_pfn
> +static inline unsigned long page_to_boot_pfn(struct page *page)
> +{
> + return page_to_pfn(page);
> +}
> +#endif

I am thinking if it's appropriate to introduce a new concept which only
exists in a certain system of a certain ARCH. Is it unavoidable? If have
to can we name it as kexec_page_to_pfn/kexec_pfn_to_page, etc? People
might not need to know about boot view physical address and kernel view
physical address things when they just want to understand kexec
implementation related to one ARCH except of ARM, even related to ARM
but not Keystone 2.

> +
> +#ifndef boot_pfn_to_page
> +static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
> +{
> + return pfn_to_page(boot_pfn);
> +}
> +#endif
> +
> +#ifndef phys_to_boot_phys
> +static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
> +{
> + return phys;
> +}
> +#endif
> +
> +#ifndef boot_phys_to_phys
> +static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
> +{
> + return boot_phys;
> +}
> +#endif
> +
> +static inline unsigned long virt_to_boot_phys(void *addr)
> +{
> + return phys_to_boot_phys(__pa((unsigned long)addr));
> +}
> +
> +static inline void *boot_phys_to_virt(unsigned long entry)
> +{
> + return phys_to_virt(boot_phys_to_phys(entry));
> +}
> +
>  #else /* !CONFIG_KEXEC_CORE */
>  struct pt_regs;
>  struct task_struct;
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index ee70aef5cd81..dd49d572a5e2 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -48,7 +48,8 @@ static int kimage_alloc_init(struct kimage **rimage, 
> unsigned long entry,
>  
>   if (kexec_on_panic) {
>   /* Verify we have a valid entry point */
> - if ((entry < crashk_res.start) || (entry > crashk_res.end))
> + if ((entry < phys_to_boot_phys(crashk_res.start)) ||
> + (entry > phys_to_boot_phys(crashk_res.end)))
>   return -EADDRNOTAVAIL;
>   }
>  
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index f9847e5822e6..d04940ccc58d 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -229,8 +229,8 @@ int sanity_check_segment_list(struct kimage *image)
>   mstart = image->segment[i].mem;
>   mend = mstart + image->segment[i].memsz - 1;
>   /* Ensure we are within the crash kernel limits */
> - if ((mstart < crashk_res.start) ||
> - (mend > crashk_res.end))
> + if ((mstart < phys_to_boot_phys(crashk_res.start)) ||
> + (mend > phys_to_boot_phys(crashk_res.end)))
>   return result;
>   }
>   }
> @@ -354,7 +354,7 @@ static struct page 
> *kimage_alloc_normal_control_pages(struct kimage *image,
>   pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
>   if (!pages)
>   break;
> - pfn   = page_to_pfn(pages);
> + pfn   = page_to_boot_pfn(pages);
>   epfn  = pfn + count;
>   addr  = pfn << PAGE_SHIFT;
>   eaddr = epfn << PAGE_SHIFT;
> @@ -480,7 +480,7 @@ static int kimage_add_entry(struct kimage *image, 
> kimage_entry_t entry)
>   return -ENOMEM;
>  
>   ind_page = page_address(page);
> - *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
> + *image->entry = virt_to_boot_phys(ind_page) | IND_INDIRECTION;
>   image->entry = ind_page;
>   image->last_entry = ind_page +
> ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
> @@ -535,13 +535,13 @@ void kimage_terminate(struct kimage *image)
>  #define for_each_kimage_entry(image, ptr, entry) \
>   for (ptr = >head; (entry = *ptr) && !(entry & IND_DONE); \
>   ptr = (entry & IND_INDIRECTION) ? \
> - phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
> + boot_phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
>  
>  static void kimage_free_entry(kimage_entry_t entry)
>  {
>   struct page *page;
>  
> - page = pfn_to_page(entry >> PAGE_SHIFT);
> + page = boot_pfn_to_page(entry >> PAGE_SHIFT);
>   kimage_free_pages(page);
>  }
>  
> @@ -635,7 +635,7 @@ static struct page *kimage_alloc_page(struct kimage 
> *image,
>* have a match.
>*/
>   list_for_each_entry(page, >dest_pages, lru) {
> - addr =

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

2016-05-11 Thread Russell King - ARM Linux

I was going to send the patches to Andrew, but then I noticed this
one has received no acks.  What's the situation for this patch?

On Thu, Apr 28, 2016 at 10:28:40AM +0100, Russell King wrote:
> kexec physical addresses are the boot-time view of the system.  For
> certain ARM systems (such as Keystone 2), the boot view of the system
> does not match the kernel's view of the system: the boot view uses a
> special alias in the lower 4GB of the physical address space.
> 
> To cater for these kinds of setups, we need to translate between the
> boot view physical addresses and the normal kernel view physical
> addresses.  This patch extracts the current transation points into
> linux/kexec.h, and allows an architecture to override the functions.
> 
> Due to the translations required, we unfortunately end up with six
> translation functions, which are reduced down to four that the
> architecture can override.
> 
> Signed-off-by: Russell King 
> ---
>  include/linux/kexec.h | 38 ++
>  kernel/kexec.c|  3 ++-
>  kernel/kexec_core.c   | 26 +-
>  3 files changed, 53 insertions(+), 14 deletions(-)
> 
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 52a3a221bcb2..99cb9dac7909 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -318,6 +318,44 @@ int __weak arch_kexec_apply_relocations_add(const 
> Elf_Ehdr *ehdr,
>  int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr 
> *sechdrs,
>   unsigned int relsec);
>  
> +#ifndef page_to_boot_pfn
> +static inline unsigned long page_to_boot_pfn(struct page *page)
> +{
> + return page_to_pfn(page);
> +}
> +#endif
> +
> +#ifndef boot_pfn_to_page
> +static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
> +{
> + return pfn_to_page(boot_pfn);
> +}
> +#endif
> +
> +#ifndef phys_to_boot_phys
> +static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
> +{
> + return phys;
> +}
> +#endif
> +
> +#ifndef boot_phys_to_phys
> +static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
> +{
> + return boot_phys;
> +}
> +#endif
> +
> +static inline unsigned long virt_to_boot_phys(void *addr)
> +{
> + return phys_to_boot_phys(__pa((unsigned long)addr));
> +}
> +
> +static inline void *boot_phys_to_virt(unsigned long entry)
> +{
> + return phys_to_virt(boot_phys_to_phys(entry));
> +}
> +
>  #else /* !CONFIG_KEXEC_CORE */
>  struct pt_regs;
>  struct task_struct;
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index ee70aef5cd81..dd49d572a5e2 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -48,7 +48,8 @@ static int kimage_alloc_init(struct kimage **rimage, 
> unsigned long entry,
>  
>   if (kexec_on_panic) {
>   /* Verify we have a valid entry point */
> - if ((entry < crashk_res.start) || (entry > crashk_res.end))
> + if ((entry < phys_to_boot_phys(crashk_res.start)) ||
> + (entry > phys_to_boot_phys(crashk_res.end)))
>   return -EADDRNOTAVAIL;
>   }
>  
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index f9847e5822e6..d04940ccc58d 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -229,8 +229,8 @@ int sanity_check_segment_list(struct kimage *image)
>   mstart = image->segment[i].mem;
>   mend = mstart + image->segment[i].memsz - 1;
>   /* Ensure we are within the crash kernel limits */
> - if ((mstart < crashk_res.start) ||
> - (mend > crashk_res.end))
> + if ((mstart < phys_to_boot_phys(crashk_res.start)) ||
> + (mend > phys_to_boot_phys(crashk_res.end)))
>   return result;
>   }
>   }
> @@ -354,7 +354,7 @@ static struct page 
> *kimage_alloc_normal_control_pages(struct kimage *image,
>   pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
>   if (!pages)
>   break;
> - pfn   = page_to_pfn(pages);
> + pfn   = page_to_boot_pfn(pages);
>   epfn  = pfn + count;
>   addr  = pfn << PAGE_SHIFT;
>   eaddr = epfn << PAGE_SHIFT;
> @@ -480,7 +480,7 @@ static int kimage_add_entry(struct kimage *image, 
> kimage_entry_t entry)
>   return -ENOMEM;
>  
>   ind_page = page_address(page);
> - *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
> + *image->entry = virt_to_boot_phys(ind_page) | IND_INDIRECTION;
>   image->entry = ind_page;
>   image->last_entry = ind_page +
> ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
> @@ -535,13 +535,13 @@ void kimage_terminate(struct kimage *image)
>  #define for_each_kimage_entry(image, ptr,

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

2016-04-29 Thread Russell King - ARM Linux

On Fri, Apr 29, 2016 at 08:44:29PM +0530, Pratyush Anand wrote:
> On Thu, Apr 28, 2016 at 2:58 PM, Russell King
>  wrote:
> > kexec physical addresses are the boot-time view of the system.  For
> > certain ARM systems (such as Keystone 2), the boot view of the system
> > does not match the kernel's view of the system: the boot view uses a
> > special alias in the lower 4GB of the physical address space.
> >
> > To cater for these kinds of setups, we need to translate between the
> > boot view physical addresses and the normal kernel view physical
> > addresses.  This patch extracts the current transation points into
> > linux/kexec.h, and allows an architecture to override the functions.
> >
> > Due to the translations required, we unfortunately end up with six
> > translation functions, which are reduced down to four that the
> > architecture can override.
> >
> > Signed-off-by: Russell King 
> 
> I must be missing something when I am thinking that, had we passed
> arch_phys_to_idmap_offset to user space, this patch would not have
> been needed, and things would have been more simpler. Please help me
> to understand why passing arch_phys_to_idmap_offset to user space
> would not be a good idea.

Sorry, I disagree.

Even if we thought that passing the offset to userspace would be a
good idea, it does nothing to solve each site in this patch.  This
patch would still be necessary.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 11/12] kexec: allow architectures to override boot mapping

2016-04-28 Thread Russell King

kexec physical addresses are the boot-time view of the system.  For
certain ARM systems (such as Keystone 2), the boot view of the system
does not match the kernel's view of the system: the boot view uses a
special alias in the lower 4GB of the physical address space.

To cater for these kinds of setups, we need to translate between the
boot view physical addresses and the normal kernel view physical
addresses.  This patch extracts the current transation points into
linux/kexec.h, and allows an architecture to override the functions.

Due to the translations required, we unfortunately end up with six
translation functions, which are reduced down to four that the
architecture can override.

Signed-off-by: Russell King 
---
 include/linux/kexec.h | 38 ++
 kernel/kexec.c|  3 ++-
 kernel/kexec_core.c   | 26 +-
 3 files changed, 53 insertions(+), 14 deletions(-)

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 52a3a221bcb2..99cb9dac7909 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -318,6 +318,44 @@ int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr 
*ehdr,
 int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr 
*sechdrs,
unsigned int relsec);
 
+#ifndef page_to_boot_pfn
+static inline unsigned long page_to_boot_pfn(struct page *page)
+{
+   return page_to_pfn(page);
+}
+#endif
+
+#ifndef boot_pfn_to_page
+static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
+{
+   return pfn_to_page(boot_pfn);
+}
+#endif
+
+#ifndef phys_to_boot_phys
+static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
+{
+   return phys;
+}
+#endif
+
+#ifndef boot_phys_to_phys
+static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
+{
+   return boot_phys;
+}
+#endif
+
+static inline unsigned long virt_to_boot_phys(void *addr)
+{
+   return phys_to_boot_phys(__pa((unsigned long)addr));
+}
+
+static inline void *boot_phys_to_virt(unsigned long entry)
+{
+   return phys_to_virt(boot_phys_to_phys(entry));
+}
+
 #else /* !CONFIG_KEXEC_CORE */
 struct pt_regs;
 struct task_struct;
diff --git a/kernel/kexec.c b/kernel/kexec.c
index ee70aef5cd81..dd49d572a5e2 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -48,7 +48,8 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned 
long entry,
 
if (kexec_on_panic) {
/* Verify we have a valid entry point */
-   if ((entry < crashk_res.start) || (entry > crashk_res.end))
+   if ((entry < phys_to_boot_phys(crashk_res.start)) ||
+   (entry > phys_to_boot_phys(crashk_res.end)))
return -EADDRNOTAVAIL;
}
 
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index f9847e5822e6..d04940ccc58d 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -229,8 +229,8 @@ int sanity_check_segment_list(struct kimage *image)
mstart = image->segment[i].mem;
mend = mstart + image->segment[i].memsz - 1;
/* Ensure we are within the crash kernel limits */
-   if ((mstart < crashk_res.start) ||
-   (mend > crashk_res.end))
+   if ((mstart < phys_to_boot_phys(crashk_res.start)) ||
+   (mend > phys_to_boot_phys(crashk_res.end)))
return result;
}
}
@@ -354,7 +354,7 @@ static struct page 
*kimage_alloc_normal_control_pages(struct kimage *image,
pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
if (!pages)
break;
-   pfn   = page_to_pfn(pages);
+   pfn   = page_to_boot_pfn(pages);
epfn  = pfn + count;
addr  = pfn << PAGE_SHIFT;
eaddr = epfn << PAGE_SHIFT;
@@ -480,7 +480,7 @@ static int kimage_add_entry(struct kimage *image, 
kimage_entry_t entry)
return -ENOMEM;
 
ind_page = page_address(page);
-   *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
+   *image->entry = virt_to_boot_phys(ind_page) | IND_INDIRECTION;
image->entry = ind_page;
image->last_entry = ind_page +
  ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
@@ -535,13 +535,13 @@ void kimage_terminate(struct kimage *image)
 #define for_each_kimage_entry(image, ptr, entry) \
for (ptr = >head; (entry = *ptr) && !(entry & IND_DONE); \
ptr = (entry & IND_INDIRECTION) ? \
-   phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
+   boot_phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
 
 static void kimage_free_entry(kimage_entry_t entry)
 {
struct page *page;
 
-

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

Re: [PATCH 11/12] kexec: allow architectures to override boot mapping

[PATCH 11/12] kexec: allow architectures to override boot mapping

5 matches

Site Navigation

Mail list logo

Footer information