Re: [PATCH 02/11] efi: Remove EFI_PAGE_SHIFT and EFI_PAGE_SIZE

[Matt Fleming <matt-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>]

On Thu, 19 Sep, at 04:54:45PM, Borislav Petkov wrote:
> From: Borislav Petkov <bp-l3A5Bk7waGM@public.gmane.org>
> 
> ... and use the good old standard defines which we all know. Also,
> simplify math to shift by PAGE_SHIFT instead of multiplying by
> PAGE_SIZE.
> 
> Signed-off-by: Borislav Petkov <bp-l3A5Bk7waGM@public.gmane.org>
> ---
>  arch/x86/boot/compressed/eboot.c | 12 ++++++------
>  arch/x86/boot/compressed/eboot.h |  1 -
>  arch/x86/platform/efi/efi.c      | 22 +++++++++++-----------
>  include/linux/efi.h              |  6 ++----
>  4 files changed, 19 insertions(+), 22 deletions(-)

I'm pulling in Leif and Roy just so they're aware of this change,
because while PAGE_SHIFT is always 12 on x86, that's not true for arm64.

However, I imagine that much work would be needed to allow for page
sizes other than 4K, so I am definitely going to take this patch.

> diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
> index b7388a425f09..5c440bf769a8 100644
> --- a/arch/x86/boot/compressed/eboot.c
> +++ b/arch/x86/boot/compressed/eboot.c
> @@ -96,7 +96,7 @@ static efi_status_t high_alloc(unsigned long size, unsigned long align,
>  	if (status != EFI_SUCCESS)
>  		goto fail;
>  
> -	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
> +	nr_pages = round_up(size, PAGE_SIZE) / PAGE_SIZE;
>  again:
>  	for (i = 0; i < map_size / desc_size; i++) {
>  		efi_memory_desc_t *desc;
> @@ -111,7 +111,7 @@ again:
>  			continue;
>  
>  		start = desc->phys_addr;
> -		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
> +		end = start + (desc->num_pages << PAGE_SHIFT);
>  
>  		if ((start + size) > end || (start + size) > max)
>  			continue;
> @@ -173,7 +173,7 @@ static efi_status_t low_alloc(unsigned long size, unsigned long align,
>  	if (status != EFI_SUCCESS)
>  		goto fail;
>  
> -	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
> +	nr_pages = round_up(size, PAGE_SIZE) / PAGE_SIZE;
>  	for (i = 0; i < map_size / desc_size; i++) {
>  		efi_memory_desc_t *desc;
>  		unsigned long m = (unsigned long)map;
> @@ -188,7 +188,7 @@ static efi_status_t low_alloc(unsigned long size, unsigned long align,
>  			continue;
>  
>  		start = desc->phys_addr;
> -		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
> +		end = start + (desc->num_pages << PAGE_SHIFT);
>  
>  		/*
>  		 * Don't allocate at 0x0. It will confuse code that
> @@ -224,7 +224,7 @@ static void low_free(unsigned long size, unsigned long addr)
>  {
>  	unsigned long nr_pages;
>  
> -	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
> +	nr_pages = round_up(size, PAGE_SIZE) / PAGE_SIZE;
>  	efi_call_phys2(sys_table->boottime->free_pages, addr, nr_pages);
>  }
>  
> @@ -1128,7 +1128,7 @@ static efi_status_t relocate_kernel(struct setup_header *hdr)
>  	 * possible.
>  	 */
>  	start = hdr->pref_address;
> -	nr_pages = round_up(hdr->init_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
> +	nr_pages = round_up(hdr->init_size, PAGE_SIZE) / PAGE_SIZE;
>  
>  	status = efi_call_phys4(sys_table->boottime->allocate_pages,
>  				EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
> diff --git a/arch/x86/boot/compressed/eboot.h b/arch/x86/boot/compressed/eboot.h
> index e5b0a8f91c5f..786398c1bb9a 100644
> --- a/arch/x86/boot/compressed/eboot.h
> +++ b/arch/x86/boot/compressed/eboot.h
> @@ -11,7 +11,6 @@
>  
>  #define DESC_TYPE_CODE_DATA	(1 << 0)
>  
> -#define EFI_PAGE_SIZE		(1UL << EFI_PAGE_SHIFT)
>  #define EFI_READ_CHUNK_SIZE	(1024 * 1024)
>  
>  #define EFI_CONSOLE_OUT_DEVICE_GUID    \
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index 7cec1e9e5494..538c1e6b7b2c 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -339,7 +339,7 @@ static void __init do_add_efi_memmap(void)
>  	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>  		efi_memory_desc_t *md = p;
>  		unsigned long long start = md->phys_addr;
> -		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
> +		unsigned long long size = md->num_pages << PAGE_SHIFT;
>  		int e820_type;
>  
>  		switch (md->type) {
> @@ -416,8 +416,8 @@ static void __init print_efi_memmap(void)
>  		pr_info("mem%02u: type=%u, attr=0x%llx, "
>  			"range=[0x%016llx-0x%016llx) (%lluMB)\n",
>  			i, md->type, md->attribute, md->phys_addr,
> -			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
> -			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
> +			md->phys_addr + (md->num_pages << PAGE_SHIFT),
> +			(md->num_pages >> (20 - PAGE_SHIFT)));
>  	}
>  #endif  /*  EFI_DEBUG  */
>  }
> @@ -429,7 +429,7 @@ void __init efi_reserve_boot_services(void)
>  	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>  		efi_memory_desc_t *md = p;
>  		u64 start = md->phys_addr;
> -		u64 size = md->num_pages << EFI_PAGE_SHIFT;
> +		u64 size = md->num_pages << PAGE_SHIFT;
>  
>  		if (md->type != EFI_BOOT_SERVICES_CODE &&
>  		    md->type != EFI_BOOT_SERVICES_DATA)
> @@ -473,7 +473,7 @@ void __init efi_free_boot_services(void)
>  	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>  		efi_memory_desc_t *md = p;
>  		unsigned long long start = md->phys_addr;
> -		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
> +		unsigned long long size = md->num_pages << PAGE_SHIFT;
>  
>  		if (md->type != EFI_BOOT_SERVICES_CODE &&
>  		    md->type != EFI_BOOT_SERVICES_DATA)
> @@ -825,7 +825,7 @@ void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
>  		return NULL;
>  	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>  		efi_memory_desc_t *md = p;
> -		u64 size = md->num_pages << EFI_PAGE_SHIFT;
> +		u64 size = md->num_pages << PAGE_SHIFT;
>  		u64 end = md->phys_addr + size;
>  		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
>  		    md->type != EFI_BOOT_SERVICES_CODE &&
> @@ -843,7 +843,7 @@ void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
>  
>  void efi_memory_uc(u64 addr, unsigned long size)
>  {
> -	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
> +	unsigned long page_shift = 1UL << PAGE_SHIFT;
>  	u64 npages;
>  
>  	npages = round_up(size, page_shift) / page_shift;
> @@ -896,7 +896,7 @@ void __init efi_enter_virtual_mode(void)
>  			continue;
>  		}
>  
> -		prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
> +		prev_size = prev_md->num_pages << PAGE_SHIFT;
>  
>  		if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
>  			prev_md->num_pages += md->num_pages;
> @@ -914,7 +914,7 @@ void __init efi_enter_virtual_mode(void)
>  		    md->type != EFI_BOOT_SERVICES_DATA)
>  			continue;
>  
> -		size = md->num_pages << EFI_PAGE_SHIFT;
> +		size = md->num_pages << PAGE_SHIFT;
>  		end = md->phys_addr + size;
>  
>  		start_pfn = PFN_DOWN(md->phys_addr);
> @@ -1011,7 +1011,7 @@ u32 efi_mem_type(unsigned long phys_addr)
>  		md = p;
>  		if ((md->phys_addr <= phys_addr) &&
>  		    (phys_addr < (md->phys_addr +
> -				  (md->num_pages << EFI_PAGE_SHIFT))))
> +				  (md->num_pages << PAGE_SHIFT))))
>  			return md->type;
>  	}
>  	return 0;
> @@ -1026,7 +1026,7 @@ u64 efi_mem_attributes(unsigned long phys_addr)
>  		md = p;
>  		if ((md->phys_addr <= phys_addr) &&
>  		    (phys_addr < (md->phys_addr +
> -				  (md->num_pages << EFI_PAGE_SHIFT))))
> +				  (md->num_pages << PAGE_SHIFT))))
>  			return md->attribute;
>  	}
>  	return 0;
> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index 5f8f176154f7..fa47d80ab4b5 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -95,8 +95,6 @@ typedef	struct {
>  #define EFI_MEMORY_RUNTIME	((u64)0x8000000000000000ULL)	/* range requires runtime mapping */
>  #define EFI_MEMORY_DESCRIPTOR_VERSION	1
>  
> -#define EFI_PAGE_SHIFT		12
> -
>  typedef struct {
>  	u32 type;
>  	u32 pad;
> @@ -611,7 +609,7 @@ static inline int efi_range_is_wc(unsigned long start, unsigned long len)
>  {
>  	unsigned long i;
>  
> -	for (i = 0; i < len; i += (1UL << EFI_PAGE_SHIFT)) {
> +	for (i = 0; i < len; i += PAGE_SIZE) {
>  		unsigned long paddr = __pa(start + i);
>  		if (!(efi_mem_attributes(paddr) & EFI_MEMORY_WC))
>  			return 0;
> @@ -728,7 +726,7 @@ struct efi_generic_dev_path {
>  
>  static inline void memrange_efi_to_native(u64 *addr, u64 *npages)
>  {
> -	*npages = PFN_UP(*addr + (*npages<<EFI_PAGE_SHIFT)) - PFN_DOWN(*addr);
> +	*npages = PFN_UP(*addr + (*npages << PAGE_SHIFT)) - PFN_DOWN(*addr);
>  	*addr &= PAGE_MASK;
>  }
>  
> -- 
> 1.8.4
> 

-- 
Matt Fleming, Intel Open Source Technology Center