* [PATCH 0/2] arm: add early_ioremap support
@ 2014-07-09 9:39 Leif Lindholm
2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm
` (3 more replies)
0 siblings, 4 replies; 17+ messages in thread
From: Leif Lindholm @ 2014-07-09 9:39 UTC (permalink / raw)
To: linux-arm-kernel
early_ioremap()/early_memremap() create temporary virtual mappings
in the fixmap region during boot time. Part of the support now exists
in core code, but depends on the generic fixmap support.
This set converts arm to use the generic fixmap support, and adds the
architecture-specific part of early_ioremap support.
The fixmap/kmap changes in 3.15 complicated things slightly compared
to previous iterations of these patches - this version works around
that by introducing local macros in arm/mm/highmem.c.
Tested on TC2 and software models, with/without LPAE.
Mark Salter (2):
arm: use generic fixmap.h
arm: add early_ioremap support
arch/arm/Kconfig | 11 ++++++
arch/arm/include/asm/Kbuild | 1 +
arch/arm/include/asm/fixmap.h | 45 +++++++++++++--------
arch/arm/include/asm/io.h | 1 +
arch/arm/kernel/setup.c | 3 ++
arch/arm/mm/Makefile | 1 +
arch/arm/mm/early_ioremap.c | 86 +++++++++++++++++++++++++++++++++++++++++
arch/arm/mm/highmem.c | 13 ++++---
arch/arm/mm/init.c | 2 +-
arch/arm/mm/mmu.c | 2 +
10 files changed, 143 insertions(+), 22 deletions(-)
create mode 100644 arch/arm/mm/early_ioremap.c
--
1.7.10.4
^ permalink raw reply [flat|nested] 17+ messages in thread* [PATCH 1/2] arm: use generic fixmap.h 2014-07-09 9:39 [PATCH 0/2] arm: add early_ioremap support Leif Lindholm @ 2014-07-09 9:39 ` Leif Lindholm 2014-07-09 20:49 ` Mark Salter 2014-07-22 16:39 ` Tomasz Figa 2014-07-09 9:39 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm ` (2 subsequent siblings) 3 siblings, 2 replies; 17+ messages in thread From: Leif Lindholm @ 2014-07-09 9:39 UTC (permalink / raw) To: linux-arm-kernel From: Mark Salter <msalter@redhat.com> ARM is different from other architectures in that fixmap pages are indexed with a positive offset from FIXADDR_START. Other architectures index with a negative offset from FIXADDR_TOP. In order to use the generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be inclusive of the useable range. That is, FIXADDR_TOP is the virtual address of the topmost fixed page. The newly defined FIXADDR_END is the first virtual address past the fixed mappings. The patch also introduces local helper macros in highmem.c to reverse the iteration order of fixmap pages. Signed-off-by: Mark Salter <msalter@redhat.com> [Rebased to 3.16-rc4, reverse kmap fixmap traversal] Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> --- arch/arm/include/asm/fixmap.h | 45 ++++++++++++++++++++++++++--------------- arch/arm/mm/highmem.c | 13 +++++++----- arch/arm/mm/init.c | 2 +- 3 files changed, 38 insertions(+), 22 deletions(-) diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h index 74124b0..8992431 100644 --- a/arch/arm/include/asm/fixmap.h +++ b/arch/arm/include/asm/fixmap.h @@ -1,28 +1,41 @@ #ifndef _ASM_FIXMAP_H #define _ASM_FIXMAP_H +#include <asm/pgtable.h> + #define FIXADDR_START 0xffc00000UL -#define FIXADDR_TOP 0xffe00000UL -#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) +#define FIXADDR_END 0xffe00000UL +#define FIXADDR_SIZE (FIXADDR_END - FIXADDR_START) +#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) #define FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) -#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) -#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) +enum fixed_addresses { + FIX_KMAP_BEGIN, + FIX_KMAP_END = FIX_KMAP_NR_PTES - 1, + __end_of_fixed_addresses +}; + +/* + * Temporary boot-time mappings, used by early_ioremap(), + * before ioremap() is functional. + * + * (P)re-using the last pmd of the FIXADDR region, which is used for + * highmem later on, and statically aligned to 1MB. + * Growing down from FIXADDR_TOP + */ +#define NR_FIX_BTMAPS 32 +#define FIX_BTMAPS_SLOTS (PTRS_PER_PTE / NR_FIX_BTMAPS) +#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) +#define FIX_BTMAP_END FIX_KMAP_BEGIN +#define FIX_BTMAP_BEGIN (FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1) -extern void __this_fixmap_does_not_exist(void); +#define FIXMAP_PAGE_NORMAL (L_PTE_MT_WRITEBACK | L_PTE_YOUNG | L_PTE_PRESENT) +#define FIXMAP_PAGE_IO (L_PTE_MT_DEV_NONSHARED | L_PTE_YOUNG | L_PTE_PRESENT) -static inline unsigned long fix_to_virt(const unsigned int idx) -{ - if (idx >= FIX_KMAP_NR_PTES) - __this_fixmap_does_not_exist(); - return __fix_to_virt(idx); -} +extern void __early_set_fixmap(enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags); -static inline unsigned int virt_to_fix(const unsigned long vaddr) -{ - BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); - return __virt_to_fix(vaddr); -} +#include <asm-generic/fixmap.h> #endif diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 45aeaac..3c59cdf 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c @@ -20,16 +20,19 @@ pte_t *fixmap_page_table; +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __fix_to_virt(x)) + static inline void set_fixmap_pte(int idx, pte_t pte) { - unsigned long vaddr = __fix_to_virt(idx); + unsigned long vaddr = __kmap_fix_to_virt(idx); set_pte_ext(fixmap_page_table + idx, pte, 0); local_flush_tlb_kernel_page(vaddr); } static inline pte_t get_fixmap_pte(unsigned long vaddr) { - unsigned long idx = __virt_to_fix(vaddr); + unsigned long idx = __kmap_virt_to_fix(vaddr); return *(fixmap_page_table + idx); } @@ -78,7 +81,7 @@ void *kmap_atomic(struct page *page) type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); + vaddr = __kmap_fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM /* * With debugging enabled, kunmap_atomic forces that entry to 0. @@ -109,7 +112,7 @@ void __kunmap_atomic(void *kvaddr) if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); #ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(vaddr != __fix_to_virt(idx)); + BUG_ON(vaddr != __kmap_fix_to_virt(idx)); set_fixmap_pte(idx, __pte(0)); #else (void) idx; /* to kill a warning */ @@ -132,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); + vaddr = __kmap_fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(*(fixmap_page_table + idx))); #endif diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 659c75d..ad82c05 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -570,7 +570,7 @@ void __init mem_init(void) MLK(DTCM_OFFSET, (unsigned long) dtcm_end), MLK(ITCM_OFFSET, (unsigned long) itcm_end), #endif - MLK(FIXADDR_START, FIXADDR_TOP), + MLK(FIXADDR_START, FIXADDR_END), MLM(VMALLOC_START, VMALLOC_END), MLM(PAGE_OFFSET, (unsigned long)high_memory), #ifdef CONFIG_HIGHMEM -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH 1/2] arm: use generic fixmap.h 2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm @ 2014-07-09 20:49 ` Mark Salter 2014-07-18 14:33 ` Leif Lindholm 2014-07-22 16:39 ` Tomasz Figa 1 sibling, 1 reply; 17+ messages in thread From: Mark Salter @ 2014-07-09 20:49 UTC (permalink / raw) To: linux-arm-kernel On Wed, 2014-07-09 at 10:39 +0100, Leif Lindholm wrote: > From: Mark Salter <msalter@redhat.com> > > ARM is different from other architectures in that fixmap pages are > indexed with a positive offset from FIXADDR_START. Other architectures > index with a negative offset from FIXADDR_TOP. In order to use the > generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be > inclusive of the useable range. That is, FIXADDR_TOP is the virtual > address of the topmost fixed page. The newly defined FIXADDR_END is > the first virtual address past the fixed mappings. > > The patch also introduces local helper macros in highmem.c to reverse > the iteration order of fixmap pages. > > Signed-off-by: Mark Salter <msalter@redhat.com> > [Rebased to 3.16-rc4, reverse kmap fixmap traversal] > Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> > --- > arch/arm/include/asm/fixmap.h | 45 ++++++++++++++++++++++++++--------------- > arch/arm/mm/highmem.c | 13 +++++++----- > arch/arm/mm/init.c | 2 +- > 3 files changed, 38 insertions(+), 22 deletions(-) > > diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h > index 74124b0..8992431 100644 > --- a/arch/arm/include/asm/fixmap.h > +++ b/arch/arm/include/asm/fixmap.h > @@ -1,28 +1,41 @@ > #ifndef _ASM_FIXMAP_H > #define _ASM_FIXMAP_H > > +#include <asm/pgtable.h> > + > #define FIXADDR_START 0xffc00000UL > -#define FIXADDR_TOP 0xffe00000UL > -#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) > +#define FIXADDR_END 0xffe00000UL > +#define FIXADDR_SIZE (FIXADDR_END - FIXADDR_START) > +#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) > > #define FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) > > -#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) > -#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) > +enum fixed_addresses { > + FIX_KMAP_BEGIN, > + FIX_KMAP_END = FIX_KMAP_NR_PTES - 1, > + __end_of_fixed_addresses > +}; > + > +/* > + * Temporary boot-time mappings, used by early_ioremap(), > + * before ioremap() is functional. > + * > + * (P)re-using the last pmd of the FIXADDR region, which is used for > + * highmem later on, and statically aligned to 1MB. > + * Growing down from FIXADDR_TOP > + */ > +#define NR_FIX_BTMAPS 32 > +#define FIX_BTMAPS_SLOTS (PTRS_PER_PTE / NR_FIX_BTMAPS) > +#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) > +#define FIX_BTMAP_END FIX_KMAP_BEGIN > +#define FIX_BTMAP_BEGIN (FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1) > > -extern void __this_fixmap_does_not_exist(void); > +#define FIXMAP_PAGE_NORMAL (L_PTE_MT_WRITEBACK | L_PTE_YOUNG | L_PTE_PRESENT) > +#define FIXMAP_PAGE_IO (L_PTE_MT_DEV_NONSHARED | L_PTE_YOUNG | L_PTE_PRESENT) > > -static inline unsigned long fix_to_virt(const unsigned int idx) > -{ > - if (idx >= FIX_KMAP_NR_PTES) > - __this_fixmap_does_not_exist(); > - return __fix_to_virt(idx); > -} > +extern void __early_set_fixmap(enum fixed_addresses idx, > + phys_addr_t phys, pgprot_t flags); > > -static inline unsigned int virt_to_fix(const unsigned long vaddr) > -{ > - BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); > - return __virt_to_fix(vaddr); > -} > +#include <asm-generic/fixmap.h> > > #endif > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c > index 45aeaac..3c59cdf 100644 > --- a/arch/arm/mm/highmem.c > +++ b/arch/arm/mm/highmem.c > @@ -20,16 +20,19 @@ > > pte_t *fixmap_page_table; > > +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) FIX_KMAP_END - (x) ? > +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __fix_to_virt(x)) shouldn't this use __virt_to_fix(x)? > + > static inline void set_fixmap_pte(int idx, pte_t pte) > { > - unsigned long vaddr = __fix_to_virt(idx); > + unsigned long vaddr = __kmap_fix_to_virt(idx); > set_pte_ext(fixmap_page_table + idx, pte, 0); > local_flush_tlb_kernel_page(vaddr); > } > > static inline pte_t get_fixmap_pte(unsigned long vaddr) > { > - unsigned long idx = __virt_to_fix(vaddr); > + unsigned long idx = __kmap_virt_to_fix(vaddr); > return *(fixmap_page_table + idx); > } > > @@ -78,7 +81,7 @@ void *kmap_atomic(struct page *page) > type = kmap_atomic_idx_push(); > > idx = type + KM_TYPE_NR * smp_processor_id(); > - vaddr = __fix_to_virt(idx); > + vaddr = __kmap_fix_to_virt(idx); > #ifdef CONFIG_DEBUG_HIGHMEM > /* > * With debugging enabled, kunmap_atomic forces that entry to 0. > @@ -109,7 +112,7 @@ void __kunmap_atomic(void *kvaddr) > if (cache_is_vivt()) > __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); > #ifdef CONFIG_DEBUG_HIGHMEM > - BUG_ON(vaddr != __fix_to_virt(idx)); > + BUG_ON(vaddr != __kmap_fix_to_virt(idx)); > set_fixmap_pte(idx, __pte(0)); > #else > (void) idx; /* to kill a warning */ > @@ -132,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) > > type = kmap_atomic_idx_push(); > idx = type + KM_TYPE_NR * smp_processor_id(); > - vaddr = __fix_to_virt(idx); > + vaddr = __kmap_fix_to_virt(idx); > #ifdef CONFIG_DEBUG_HIGHMEM > BUG_ON(!pte_none(*(fixmap_page_table + idx))); > #endif > diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c > index 659c75d..ad82c05 100644 > --- a/arch/arm/mm/init.c > +++ b/arch/arm/mm/init.c > @@ -570,7 +570,7 @@ void __init mem_init(void) > MLK(DTCM_OFFSET, (unsigned long) dtcm_end), > MLK(ITCM_OFFSET, (unsigned long) itcm_end), > #endif > - MLK(FIXADDR_START, FIXADDR_TOP), > + MLK(FIXADDR_START, FIXADDR_END), > MLM(VMALLOC_START, VMALLOC_END), > MLM(PAGE_OFFSET, (unsigned long)high_memory), > #ifdef CONFIG_HIGHMEM ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 1/2] arm: use generic fixmap.h 2014-07-09 20:49 ` Mark Salter @ 2014-07-18 14:33 ` Leif Lindholm 2014-07-25 19:56 ` Kees Cook 0 siblings, 1 reply; 17+ messages in thread From: Leif Lindholm @ 2014-07-18 14:33 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 04:49:02PM -0400, Mark Salter wrote: > On Wed, 2014-07-09 at 10:39 +0100, Leif Lindholm wrote: > > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c > > index 45aeaac..3c59cdf 100644 > > --- a/arch/arm/mm/highmem.c > > +++ b/arch/arm/mm/highmem.c > > @@ -20,16 +20,19 @@ > > > > pte_t *fixmap_page_table; > > > > +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) > > FIX_KMAP_END - (x) ? > > > +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __fix_to_virt(x)) > > shouldn't this use __virt_to_fix(x)? Err, clearly. Good thing I managed to mess up the end of the interface that actually isn't used anywhere in the kernel(!). Fixed in the below. / Leif >From d0a82cd19000139d32232f415bcf46f476c16561 Mon Sep 17 00:00:00 2001 From: Mark Salter <msalter@redhat.com> Date: Thu, 14 Nov 2013 11:37:32 -0500 Subject: [PATCH 1/2] arm: use generic fixmap.h ARM is different from other architectures in that fixmap pages are indexed with a positive offset from FIXADDR_START. Other architectures index with a negative offset from FIXADDR_TOP. In order to use the generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be inclusive of the useable range. That is, FIXADDR_TOP is the virtual address of the topmost fixed page. The newly defined FIXADDR_END is the first virtual address past the fixed mappings. The patch also introduces local helper macros in highmem.c to reverse the iteration order of fixmap pages. Signed-off-by: Mark Salter <msalter@redhat.com> [Rebased to 3.16-rc4, reverse kmap fixmap traversal] Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> --- arch/arm/include/asm/fixmap.h | 45 ++++++++++++++++++++++++++--------------- arch/arm/mm/highmem.c | 13 +++++++----- arch/arm/mm/init.c | 2 +- 3 files changed, 38 insertions(+), 22 deletions(-) diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h index 74124b0..8992431 100644 --- a/arch/arm/include/asm/fixmap.h +++ b/arch/arm/include/asm/fixmap.h @@ -1,28 +1,41 @@ #ifndef _ASM_FIXMAP_H #define _ASM_FIXMAP_H +#include <asm/pgtable.h> + #define FIXADDR_START 0xffc00000UL -#define FIXADDR_TOP 0xffe00000UL -#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) +#define FIXADDR_END 0xffe00000UL +#define FIXADDR_SIZE (FIXADDR_END - FIXADDR_START) +#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) #define FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) -#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) -#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) +enum fixed_addresses { + FIX_KMAP_BEGIN, + FIX_KMAP_END = FIX_KMAP_NR_PTES - 1, + __end_of_fixed_addresses +}; + +/* + * Temporary boot-time mappings, used by early_ioremap(), + * before ioremap() is functional. + * + * (P)re-using the last pmd of the FIXADDR region, which is used for + * highmem later on, and statically aligned to 1MB. + * Growing down from FIXADDR_TOP + */ +#define NR_FIX_BTMAPS 32 +#define FIX_BTMAPS_SLOTS (PTRS_PER_PTE / NR_FIX_BTMAPS) +#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) +#define FIX_BTMAP_END FIX_KMAP_BEGIN +#define FIX_BTMAP_BEGIN (FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1) -extern void __this_fixmap_does_not_exist(void); +#define FIXMAP_PAGE_NORMAL (L_PTE_MT_WRITEBACK | L_PTE_YOUNG | L_PTE_PRESENT) +#define FIXMAP_PAGE_IO (L_PTE_MT_DEV_NONSHARED | L_PTE_YOUNG | L_PTE_PRESENT) -static inline unsigned long fix_to_virt(const unsigned int idx) -{ - if (idx >= FIX_KMAP_NR_PTES) - __this_fixmap_does_not_exist(); - return __fix_to_virt(idx); -} +extern void __early_set_fixmap(enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags); -static inline unsigned int virt_to_fix(const unsigned long vaddr) -{ - BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); - return __virt_to_fix(vaddr); -} +#include <asm-generic/fixmap.h> #endif diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 45aeaac..2e5b773 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c @@ -20,16 +20,19 @@ pte_t *fixmap_page_table; +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __virt_to_fix(x)) + static inline void set_fixmap_pte(int idx, pte_t pte) { - unsigned long vaddr = __fix_to_virt(idx); + unsigned long vaddr = __kmap_fix_to_virt(idx); set_pte_ext(fixmap_page_table + idx, pte, 0); local_flush_tlb_kernel_page(vaddr); } static inline pte_t get_fixmap_pte(unsigned long vaddr) { - unsigned long idx = __virt_to_fix(vaddr); + unsigned long idx = __kmap_virt_to_fix(vaddr); return *(fixmap_page_table + idx); } @@ -78,7 +81,7 @@ void *kmap_atomic(struct page *page) type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); + vaddr = __kmap_fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM /* * With debugging enabled, kunmap_atomic forces that entry to 0. @@ -109,7 +112,7 @@ void __kunmap_atomic(void *kvaddr) if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); #ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(vaddr != __fix_to_virt(idx)); + BUG_ON(vaddr != __kmap_fix_to_virt(idx)); set_fixmap_pte(idx, __pte(0)); #else (void) idx; /* to kill a warning */ @@ -132,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); - vaddr = __fix_to_virt(idx); + vaddr = __kmap_fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(*(fixmap_page_table + idx))); #endif diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 659c75d..ad82c05 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -570,7 +570,7 @@ void __init mem_init(void) MLK(DTCM_OFFSET, (unsigned long) dtcm_end), MLK(ITCM_OFFSET, (unsigned long) itcm_end), #endif - MLK(FIXADDR_START, FIXADDR_TOP), + MLK(FIXADDR_START, FIXADDR_END), MLM(VMALLOC_START, VMALLOC_END), MLM(PAGE_OFFSET, (unsigned long)high_memory), #ifdef CONFIG_HIGHMEM -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH 1/2] arm: use generic fixmap.h 2014-07-18 14:33 ` Leif Lindholm @ 2014-07-25 19:56 ` Kees Cook 0 siblings, 0 replies; 17+ messages in thread From: Kees Cook @ 2014-07-25 19:56 UTC (permalink / raw) To: linux-arm-kernel On Fri, Jul 18, 2014 at 7:33 AM, Leif Lindholm <leif.lindholm@linaro.org> wrote: > On Wed, Jul 09, 2014 at 04:49:02PM -0400, Mark Salter wrote: >> On Wed, 2014-07-09 at 10:39 +0100, Leif Lindholm wrote: >> > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c >> > index 45aeaac..3c59cdf 100644 >> > --- a/arch/arm/mm/highmem.c >> > +++ b/arch/arm/mm/highmem.c >> > @@ -20,16 +20,19 @@ >> > >> > pte_t *fixmap_page_table; >> > >> > +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) >> >> FIX_KMAP_END - (x) ? >> >> > +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __fix_to_virt(x)) >> >> shouldn't this use __virt_to_fix(x)? > > Err, clearly. > Good thing I managed to mess up the end of the interface that actually > isn't used anywhere in the kernel(!). > > Fixed in the below. > > / > Leif > > From d0a82cd19000139d32232f415bcf46f476c16561 Mon Sep 17 00:00:00 2001 > From: Mark Salter <msalter@redhat.com> > Date: Thu, 14 Nov 2013 11:37:32 -0500 > Subject: [PATCH 1/2] arm: use generic fixmap.h > > ARM is different from other architectures in that fixmap pages are > indexed with a positive offset from FIXADDR_START. Other architectures > index with a negative offset from FIXADDR_TOP. In order to use the > generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be > inclusive of the useable range. That is, FIXADDR_TOP is the virtual > address of the topmost fixed page. The newly defined FIXADDR_END is > the first virtual address past the fixed mappings. > > The patch also introduces local helper macros in highmem.c to reverse > the iteration order of fixmap pages. > > Signed-off-by: Mark Salter <msalter@redhat.com> > [Rebased to 3.16-rc4, reverse kmap fixmap traversal] > Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> > --- > arch/arm/include/asm/fixmap.h | 45 ++++++++++++++++++++++++++--------------- > arch/arm/mm/highmem.c | 13 +++++++----- > arch/arm/mm/init.c | 2 +- > 3 files changed, 38 insertions(+), 22 deletions(-) > > diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h > index 74124b0..8992431 100644 > --- a/arch/arm/include/asm/fixmap.h > +++ b/arch/arm/include/asm/fixmap.h > @@ -1,28 +1,41 @@ > #ifndef _ASM_FIXMAP_H > #define _ASM_FIXMAP_H > > +#include <asm/pgtable.h> > + > #define FIXADDR_START 0xffc00000UL > -#define FIXADDR_TOP 0xffe00000UL > -#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) > +#define FIXADDR_END 0xffe00000UL > +#define FIXADDR_SIZE (FIXADDR_END - FIXADDR_START) > +#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) > > #define FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) > > -#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) > -#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) > +enum fixed_addresses { > + FIX_KMAP_BEGIN, > + FIX_KMAP_END = FIX_KMAP_NR_PTES - 1, > + __end_of_fixed_addresses > +}; > + > +/* > + * Temporary boot-time mappings, used by early_ioremap(), > + * before ioremap() is functional. > + * > + * (P)re-using the last pmd of the FIXADDR region, which is used for > + * highmem later on, and statically aligned to 1MB. > + * Growing down from FIXADDR_TOP > + */ > +#define NR_FIX_BTMAPS 32 > +#define FIX_BTMAPS_SLOTS (PTRS_PER_PTE / NR_FIX_BTMAPS) > +#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) > +#define FIX_BTMAP_END FIX_KMAP_BEGIN > +#define FIX_BTMAP_BEGIN (FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1) > > -extern void __this_fixmap_does_not_exist(void); > +#define FIXMAP_PAGE_NORMAL (L_PTE_MT_WRITEBACK | L_PTE_YOUNG | L_PTE_PRESENT) > +#define FIXMAP_PAGE_IO (L_PTE_MT_DEV_NONSHARED | L_PTE_YOUNG | L_PTE_PRESENT) > > -static inline unsigned long fix_to_virt(const unsigned int idx) > -{ > - if (idx >= FIX_KMAP_NR_PTES) > - __this_fixmap_does_not_exist(); > - return __fix_to_virt(idx); > -} > +extern void __early_set_fixmap(enum fixed_addresses idx, > + phys_addr_t phys, pgprot_t flags); > > -static inline unsigned int virt_to_fix(const unsigned long vaddr) > -{ > - BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); > - return __virt_to_fix(vaddr); > -} > +#include <asm-generic/fixmap.h> > > #endif > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c > index 45aeaac..2e5b773 100644 > --- a/arch/arm/mm/highmem.c > +++ b/arch/arm/mm/highmem.c > @@ -20,16 +20,19 @@ > > pte_t *fixmap_page_table; > > +#define __kmap_fix_to_virt(x) (__fix_to_virt(FIX_KMAP_NR_PTES - 1 - (x))) > +#define __kmap_virt_to_fix(x) (FIX_KMAP_NR_PTES - 1 - __virt_to_fix(x)) > + > static inline void set_fixmap_pte(int idx, pte_t pte) > { > - unsigned long vaddr = __fix_to_virt(idx); > + unsigned long vaddr = __kmap_fix_to_virt(idx); > set_pte_ext(fixmap_page_table + idx, pte, 0); > local_flush_tlb_kernel_page(vaddr); > } > > static inline pte_t get_fixmap_pte(unsigned long vaddr) > { > - unsigned long idx = __virt_to_fix(vaddr); > + unsigned long idx = __kmap_virt_to_fix(vaddr); > return *(fixmap_page_table + idx); > } > > @@ -78,7 +81,7 @@ void *kmap_atomic(struct page *page) > type = kmap_atomic_idx_push(); > > idx = type + KM_TYPE_NR * smp_processor_id(); > - vaddr = __fix_to_virt(idx); > + vaddr = __kmap_fix_to_virt(idx); > #ifdef CONFIG_DEBUG_HIGHMEM > /* > * With debugging enabled, kunmap_atomic forces that entry to 0. > @@ -109,7 +112,7 @@ void __kunmap_atomic(void *kvaddr) > if (cache_is_vivt()) > __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); > #ifdef CONFIG_DEBUG_HIGHMEM > - BUG_ON(vaddr != __fix_to_virt(idx)); > + BUG_ON(vaddr != __kmap_fix_to_virt(idx)); > set_fixmap_pte(idx, __pte(0)); > #else > (void) idx; /* to kill a warning */ > @@ -132,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) > > type = kmap_atomic_idx_push(); > idx = type + KM_TYPE_NR * smp_processor_id(); > - vaddr = __fix_to_virt(idx); > + vaddr = __kmap_fix_to_virt(idx); > #ifdef CONFIG_DEBUG_HIGHMEM > BUG_ON(!pte_none(*(fixmap_page_table + idx))); > #endif > diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c > index 659c75d..ad82c05 100644 > --- a/arch/arm/mm/init.c > +++ b/arch/arm/mm/init.c > @@ -570,7 +570,7 @@ void __init mem_init(void) > MLK(DTCM_OFFSET, (unsigned long) dtcm_end), > MLK(ITCM_OFFSET, (unsigned long) itcm_end), > #endif > - MLK(FIXADDR_START, FIXADDR_TOP), > + MLK(FIXADDR_START, FIXADDR_END), > MLM(VMALLOC_START, VMALLOC_END), > MLM(PAGE_OFFSET, (unsigned long)high_memory), > #ifdef CONFIG_HIGHMEM > -- > 1.7.10.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel I'd like to use this for kernel RO text handling too (kprobes and kgdb). Is this patch alone in good enough shape for landing in -next? I would want this added as well: https://patchwork.kernel.org/patch/3941001/ Thoughts? -Kees -- Kees Cook Chrome OS Security ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 1/2] arm: use generic fixmap.h 2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm 2014-07-09 20:49 ` Mark Salter @ 2014-07-22 16:39 ` Tomasz Figa 1 sibling, 0 replies; 17+ messages in thread From: Tomasz Figa @ 2014-07-22 16:39 UTC (permalink / raw) To: linux-arm-kernel Hi Leif, On 09.07.2014 11:39, Leif Lindholm wrote: > From: Mark Salter <msalter@redhat.com> > > ARM is different from other architectures in that fixmap pages are > indexed with a positive offset from FIXADDR_START. Other architectures > index with a negative offset from FIXADDR_TOP. In order to use the > generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be > inclusive of the useable range. That is, FIXADDR_TOP is the virtual > address of the topmost fixed page. The newly defined FIXADDR_END is > the first virtual address past the fixed mappings. > > The patch also introduces local helper macros in highmem.c to reverse > the iteration order of fixmap pages. > > Signed-off-by: Mark Salter <msalter@redhat.com> > [Rebased to 3.16-rc4, reverse kmap fixmap traversal] > Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> > --- > arch/arm/include/asm/fixmap.h | 45 ++++++++++++++++++++++++++--------------- > arch/arm/mm/highmem.c | 13 +++++++----- > arch/arm/mm/init.c | 2 +- > 3 files changed, 38 insertions(+), 22 deletions(-) > I've tried to use this series to enable earlycon without hardcoded static mappings, but apparently something is not right yet. Please see below. [snip] > -extern void __this_fixmap_does_not_exist(void); > +#define FIXMAP_PAGE_NORMAL (L_PTE_MT_WRITEBACK | L_PTE_YOUNG | L_PTE_PRESENT) > +#define FIXMAP_PAGE_IO (L_PTE_MT_DEV_NONSHARED | L_PTE_YOUNG | L_PTE_PRESENT) This set of flags gives a read-only mapping on the machine I'm testing on (Exynos4412, Cortex A9MPcore). If I use the same set of flags as used in arch/arm/mm/mmu.c for MT_DEVICE_NONSHARED then the mapping works fine. Best regards, Tomasz ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-09 9:39 [PATCH 0/2] arm: add early_ioremap support Leif Lindholm 2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm @ 2014-07-09 9:39 ` Leif Lindholm 2014-07-09 9:49 ` Russell King - ARM Linux 2014-07-22 16:48 ` Tomasz Figa 2014-07-09 9:42 ` [PATCH 0/2] " Russell King - ARM Linux 2014-07-09 9:47 ` Will Deacon 3 siblings, 2 replies; 17+ messages in thread From: Leif Lindholm @ 2014-07-09 9:39 UTC (permalink / raw) To: linux-arm-kernel From: Mark Salter <msalter@redhat.com> This patch uses the generic early_ioremap code to implement early_ioremap for ARM. The ARM-specific bits come mostly from an earlier patch from Leif Lindholm <leif.lindholm@linaro.org> here: https://lkml.org/lkml/2013/10/3/279 Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> CC: linux-arm-kernel at lists.infradead.org CC: Russell King <linux@arm.linux.org.uk> CC: Catalin Marinas <catalin.marinas@arm.com> CC: Will Deacon <will.deacon@arm.com> CC: Arnd Bergmann <arnd@arndb.de> --- arch/arm/Kconfig | 11 ++++++ arch/arm/include/asm/Kbuild | 1 + arch/arm/include/asm/io.h | 1 + arch/arm/kernel/setup.c | 3 ++ arch/arm/mm/Makefile | 1 + arch/arm/mm/early_ioremap.c | 86 +++++++++++++++++++++++++++++++++++++++++++ arch/arm/mm/mmu.c | 2 + 7 files changed, 105 insertions(+) create mode 100644 arch/arm/mm/early_ioremap.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 245058b..04b8f8a 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1800,6 +1800,17 @@ config UACCESS_WITH_MEMCPY However, if the CPU data cache is using a write-allocate mode, this option is unlikely to provide any performance gain. +config EARLY_IOREMAP + depends on MMU + bool "Provide early_ioremap() support for kernel initialization." + select GENERIC_EARLY_IOREMAP + help + Provide a mechanism for kernel initialisation code to temporarily + map, in a highmem-agnostic way, memory pages in before ioremap() + and friends are available (before paging_init() has run). It uses + the same virtual memory range as kmap so all early mappings must + be unmapped before paging_init() is called. + config SECCOMP bool prompt "Enable seccomp to safely compute untrusted bytecode" diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index f5a3576..0bc5a02 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -4,6 +4,7 @@ generic-y += auxvec.h generic-y += bitsperlong.h generic-y += cputime.h generic-y += current.h +generic-y += early_ioremap.h generic-y += emergency-restart.h generic-y += errno.h generic-y += exec.h diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index 3d23418..7b8a981 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -28,6 +28,7 @@ #include <asm/byteorder.h> #include <asm/memory.h> #include <asm-generic/pci_iomap.h> +#include <asm/early_ioremap.h> #include <xen/xen.h> /* diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 8a16ee5..aa2621a 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -36,6 +36,7 @@ #include <asm/cpu.h> #include <asm/cputype.h> #include <asm/elf.h> +#include <asm/io.h> #include <asm/procinfo.h> #include <asm/psci.h> #include <asm/sections.h> @@ -894,6 +895,8 @@ void __init setup_arch(char **cmdline_p) parse_early_param(); + early_ioremap_init(); + early_paging_init(mdesc, lookup_processor_type(read_cpuid_id())); setup_dma_zone(mdesc); sanity_check_meminfo(); diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 91da64d..1c8ce752 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_ARM_PTDUMP) += dump.o obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o +obj-$(CONFIG_EARLY_IOREMAP) += early_ioremap.o obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c new file mode 100644 index 0000000..1013109 --- /dev/null +++ b/arch/arm/mm/early_ioremap.c @@ -0,0 +1,86 @@ +/* + * early_ioremap() support for ARM + * + * Based on existing support in arch/x86/mm/ioremap.c + * + * Restrictions: currently only functional before paging_init() + */ + +#include <linux/init.h> +#include <linux/io.h> + +#include <asm/fixmap.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +#include <asm/mach/map.h> + +static pte_t bm_pte[PTRS_PER_PTE] __aligned(PTE_HWTABLE_SIZE) __initdata; + +static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) +{ + unsigned int index = pgd_index(addr); + pgd_t *pgd = cpu_get_pgd() + index; + pud_t *pud = pud_offset(pgd, addr); + pmd_t *pmd = pmd_offset(pud, addr); + + return pmd; +} + +static inline pte_t * __init early_ioremap_pte(unsigned long addr) +{ + return &bm_pte[pte_index(addr)]; +} + +void __init early_ioremap_init(void) +{ + pmd_t *pmd; + + pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); + pmd_populate_kernel(NULL, pmd, bm_pte); + + if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) { + WARN_ON(1); + pr_warn("pmd %p != %p\n", + pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))); + pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", + fix_to_virt(FIX_BTMAP_BEGIN)); + pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", + fix_to_virt(FIX_BTMAP_END)); + pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); + pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); + } + + early_ioremap_setup(); +} + +void __init __early_set_fixmap(enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags) +{ + unsigned long addr = __fix_to_virt(idx); + pte_t *pte; + u64 desc; + + if (idx > FIX_KMAP_END) { + BUG(); + return; + } + pte = early_ioremap_pte(addr); + + if (pgprot_val(flags)) + set_pte_at(NULL, addr, pte, + pfn_pte(phys >> PAGE_SHIFT, flags)); + else + pte_clear(NULL, addr, pte); + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + desc = *pte; +} + +void __init +early_ioremap_shutdown(void) +{ + pmd_t *pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); + + pmd_clear(pmd); +} diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index ab14b79..608dc36 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -36,6 +36,7 @@ #include <asm/mach/map.h> #include <asm/mach/pci.h> #include <asm/fixmap.h> +#include <asm/early_ioremap.h> #include "mm.h" #include "tcm.h" @@ -1474,6 +1475,7 @@ void __init paging_init(const struct machine_desc *mdesc) { void *zero_page; + early_ioremap_reset(); build_mem_type_table(); prepare_page_table(); map_lowmem(); -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-09 9:39 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm @ 2014-07-09 9:49 ` Russell King - ARM Linux 2014-07-09 11:48 ` Leif Lindholm 2014-07-22 16:48 ` Tomasz Figa 1 sibling, 1 reply; 17+ messages in thread From: Russell King - ARM Linux @ 2014-07-09 9:49 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 10:39:52AM +0100, Leif Lindholm wrote: > +config EARLY_IOREMAP > + depends on MMU > + bool "Provide early_ioremap() support for kernel initialization." > + select GENERIC_EARLY_IOREMAP Nit: please order as bool, then depends, then select. > diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c > index 8a16ee5..aa2621a 100644 > --- a/arch/arm/kernel/setup.c > +++ b/arch/arm/kernel/setup.c > @@ -36,6 +36,7 @@ > #include <asm/cpu.h> > #include <asm/cputype.h> > #include <asm/elf.h> > +#include <asm/io.h> Please always use linux/io.h in preference to asm/io.h. > +static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) > +{ > + unsigned int index = pgd_index(addr); > + pgd_t *pgd = cpu_get_pgd() + index; What is the reasoning for using cpu_get_pgd() ? Is there some specific reason you want to read from the hardware register rather than using the pgd_offset_k() macro here? > +void __init > +early_ioremap_shutdown(void) Nit: should be a single line. The rest of the patch looks fine, thanks. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-09 9:49 ` Russell King - ARM Linux @ 2014-07-09 11:48 ` Leif Lindholm 0 siblings, 0 replies; 17+ messages in thread From: Leif Lindholm @ 2014-07-09 11:48 UTC (permalink / raw) To: linux-arm-kernel Hi Russell, On Wed, Jul 09, 2014 at 10:49:26AM +0100, Russell King - ARM Linux wrote: > On Wed, Jul 09, 2014 at 10:39:52AM +0100, Leif Lindholm wrote: > > +config EARLY_IOREMAP > > + depends on MMU > > + bool "Provide early_ioremap() support for kernel initialization." > > + select GENERIC_EARLY_IOREMAP > > Nit: please order as bool, then depends, then select. Fixed in attached. > > diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c > > index 8a16ee5..aa2621a 100644 > > --- a/arch/arm/kernel/setup.c > > +++ b/arch/arm/kernel/setup.c > > @@ -36,6 +36,7 @@ > > #include <asm/cpu.h> > > #include <asm/cputype.h> > > #include <asm/elf.h> > > +#include <asm/io.h> > > Please always use linux/io.h in preference to asm/io.h. Fixed in attached. > > +static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) > > +{ > > + unsigned int index = pgd_index(addr); > > + pgd_t *pgd = cpu_get_pgd() + index; > > What is the reasoning for using cpu_get_pgd() ? Is there some specific > reason you want to read from the hardware register rather than using > the pgd_offset_k() macro here? No, merely picked the wrong interface, and it seemed to work. Fixed in attached. > > +void __init > > +early_ioremap_shutdown(void) > > Nit: should be a single line. Fixed in attached. > The rest of the patch looks fine, thanks. Thank you for your comments. / Leif >From 6937e88fc0bc62e125d891889334b6659f2efd28 Mon Sep 17 00:00:00 2001 From: Mark Salter <msalter@redhat.com> Date: Wed, 27 Nov 2013 10:21:11 -0500 Subject: [PATCH 2/2] arm: add early_ioremap support This patch uses the generic early_ioremap code to implement early_ioremap for ARM. The ARM-specific bits come mostly from an earlier patch from Leif Lindholm <leif.lindholm@linaro.org> here: https://lkml.org/lkml/2013/10/3/279 Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> CC: linux-arm-kernel at lists.infradead.org CC: Russell King <linux@arm.linux.org.uk> CC: Catalin Marinas <catalin.marinas@arm.com> CC: Will Deacon <will.deacon@arm.com> CC: Arnd Bergmann <arnd@arndb.de> --- arch/arm/Kconfig | 11 ++++++ arch/arm/include/asm/Kbuild | 1 + arch/arm/include/asm/io.h | 1 + arch/arm/kernel/setup.c | 3 ++ arch/arm/mm/Makefile | 1 + arch/arm/mm/early_ioremap.c | 84 +++++++++++++++++++++++++++++++++++++++++++ arch/arm/mm/mmu.c | 2 ++ 7 files changed, 103 insertions(+) create mode 100644 arch/arm/mm/early_ioremap.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 245058b..5ddafaf 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1800,6 +1800,17 @@ config UACCESS_WITH_MEMCPY However, if the CPU data cache is using a write-allocate mode, this option is unlikely to provide any performance gain. +config EARLY_IOREMAP + bool "Provide early_ioremap() support for kernel initialization." + depends on MMU + select GENERIC_EARLY_IOREMAP + help + Provide a mechanism for kernel initialisation code to temporarily + map, in a highmem-agnostic way, memory pages in before ioremap() + and friends are available (before paging_init() has run). It uses + the same virtual memory range as kmap so all early mappings must + be unmapped before paging_init() is called. + config SECCOMP bool prompt "Enable seccomp to safely compute untrusted bytecode" diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index f5a3576..0bc5a02 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -4,6 +4,7 @@ generic-y += auxvec.h generic-y += bitsperlong.h generic-y += cputime.h generic-y += current.h +generic-y += early_ioremap.h generic-y += emergency-restart.h generic-y += errno.h generic-y += exec.h diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index 3d23418..7b8a981 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -28,6 +28,7 @@ #include <asm/byteorder.h> #include <asm/memory.h> #include <asm-generic/pci_iomap.h> +#include <asm/early_ioremap.h> #include <xen/xen.h> /* diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 8a16ee5..b1f397c 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -30,6 +30,7 @@ #include <linux/bug.h> #include <linux/compiler.h> #include <linux/sort.h> +#include <linux/io.h> #include <asm/unified.h> #include <asm/cp15.h> @@ -894,6 +895,8 @@ void __init setup_arch(char **cmdline_p) parse_early_param(); + early_ioremap_init(); + early_paging_init(mdesc, lookup_processor_type(read_cpuid_id())); setup_dma_zone(mdesc); sanity_check_meminfo(); diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 91da64d..1c8ce752 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_ARM_PTDUMP) += dump.o obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o +obj-$(CONFIG_EARLY_IOREMAP) += early_ioremap.o obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c new file mode 100644 index 0000000..6444454 --- /dev/null +++ b/arch/arm/mm/early_ioremap.c @@ -0,0 +1,84 @@ +/* + * early_ioremap() support for ARM + * + * Based on existing support in arch/x86/mm/ioremap.c + * + * Restrictions: currently only functional before paging_init() + */ + +#include <linux/init.h> +#include <linux/io.h> + +#include <asm/fixmap.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +#include <asm/mach/map.h> + +static pte_t bm_pte[PTRS_PER_PTE] __aligned(PTE_HWTABLE_SIZE) __initdata; + +static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) +{ + pgd_t *pgd = pgd_offset_k(addr); + pud_t *pud = pud_offset(pgd, addr); + pmd_t *pmd = pmd_offset(pud, addr); + + return pmd; +} + +static inline pte_t * __init early_ioremap_pte(unsigned long addr) +{ + return &bm_pte[pte_index(addr)]; +} + +void __init early_ioremap_init(void) +{ + pmd_t *pmd; + + pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); + pmd_populate_kernel(NULL, pmd, bm_pte); + + if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) { + WARN_ON(1); + pr_warn("pmd %p != %p\n", + pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))); + pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", + fix_to_virt(FIX_BTMAP_BEGIN)); + pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", + fix_to_virt(FIX_BTMAP_END)); + pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); + pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); + } + + early_ioremap_setup(); +} + +void __init __early_set_fixmap(enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags) +{ + unsigned long addr = __fix_to_virt(idx); + pte_t *pte; + u64 desc; + + if (idx > FIX_KMAP_END) { + BUG(); + return; + } + pte = early_ioremap_pte(addr); + + if (pgprot_val(flags)) + set_pte_at(NULL, addr, pte, + pfn_pte(phys >> PAGE_SHIFT, flags)); + else + pte_clear(NULL, addr, pte); + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + desc = *pte; +} + +void __init early_ioremap_shutdown(void) +{ + pmd_t *pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); + + pmd_clear(pmd); +} diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index ab14b79..608dc36 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -36,6 +36,7 @@ #include <asm/mach/map.h> #include <asm/mach/pci.h> #include <asm/fixmap.h> +#include <asm/early_ioremap.h> #include "mm.h" #include "tcm.h" @@ -1474,6 +1475,7 @@ void __init paging_init(const struct machine_desc *mdesc) { void *zero_page; + early_ioremap_reset(); build_mem_type_table(); prepare_page_table(); map_lowmem(); -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-09 9:39 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm 2014-07-09 9:49 ` Russell King - ARM Linux @ 2014-07-22 16:48 ` Tomasz Figa 2014-07-22 17:11 ` Rob Herring 1 sibling, 1 reply; 17+ messages in thread From: Tomasz Figa @ 2014-07-22 16:48 UTC (permalink / raw) To: linux-arm-kernel Hi Leif, On 09.07.2014 11:39, Leif Lindholm wrote: > From: Mark Salter <msalter@redhat.com> > > This patch uses the generic early_ioremap code to implement > early_ioremap for ARM. The ARM-specific bits come mostly from > an earlier patch from Leif Lindholm <leif.lindholm@linaro.org> > here: > > https://lkml.org/lkml/2013/10/3/279 [snip] > diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c > new file mode 100644 > index 0000000..1013109 > --- /dev/null > +++ b/arch/arm/mm/early_ioremap.c > @@ -0,0 +1,86 @@ > +/* > + * early_ioremap() support for ARM > + * > + * Based on existing support in arch/x86/mm/ioremap.c > + * > + * Restrictions: currently only functional before paging_init() Uhm, that's bad... This would explain why my earlycon code generates a fault as soon as something prints after paging_init(). I'd say this feature would be much more useful if mappings were carried over paging_init(), so that mapped devices are available later as well. I'll see if I can code this on top of your patch, but unfortunately it might end up with -ENOTIME. Best regards, Tomasz ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-22 16:48 ` Tomasz Figa @ 2014-07-22 17:11 ` Rob Herring 2014-07-22 17:27 ` Tomasz Figa 0 siblings, 1 reply; 17+ messages in thread From: Rob Herring @ 2014-07-22 17:11 UTC (permalink / raw) To: linux-arm-kernel On Tue, Jul 22, 2014 at 11:48 AM, Tomasz Figa <t.figa@samsung.com> wrote: > Hi Leif, > > On 09.07.2014 11:39, Leif Lindholm wrote: >> From: Mark Salter <msalter@redhat.com> >> >> This patch uses the generic early_ioremap code to implement >> early_ioremap for ARM. The ARM-specific bits come mostly from >> an earlier patch from Leif Lindholm <leif.lindholm@linaro.org> >> here: >> >> https://lkml.org/lkml/2013/10/3/279 > > [snip] > >> diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c >> new file mode 100644 >> index 0000000..1013109 >> --- /dev/null >> +++ b/arch/arm/mm/early_ioremap.c >> @@ -0,0 +1,86 @@ >> +/* >> + * early_ioremap() support for ARM >> + * >> + * Based on existing support in arch/x86/mm/ioremap.c >> + * >> + * Restrictions: currently only functional before paging_init() > > Uhm, that's bad... This would explain why my earlycon code generates a > fault as soon as something prints after paging_init(). I'd say this > feature would be much more useful if mappings were carried over > paging_init(), so that mapped devices are available later as well. > > I'll see if I can code this on top of your patch, but unfortunately it > might end up with -ENOTIME. I have fixmap support that's needed for earlycon. Here is the branch: git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git fixmap It is based on an earlier version of patchset and not on the latest version from Leif. Unfortunately, I don't have more time to spend on it ATM. Rob ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2014-07-22 17:11 ` Rob Herring @ 2014-07-22 17:27 ` Tomasz Figa 0 siblings, 0 replies; 17+ messages in thread From: Tomasz Figa @ 2014-07-22 17:27 UTC (permalink / raw) To: linux-arm-kernel On 22.07.2014 19:11, Rob Herring wrote: > On Tue, Jul 22, 2014 at 11:48 AM, Tomasz Figa <t.figa@samsung.com> wrote: >> Hi Leif, >> >> On 09.07.2014 11:39, Leif Lindholm wrote: >>> From: Mark Salter <msalter@redhat.com> >>> >>> This patch uses the generic early_ioremap code to implement >>> early_ioremap for ARM. The ARM-specific bits come mostly from >>> an earlier patch from Leif Lindholm <leif.lindholm@linaro.org> >>> here: >>> >>> https://lkml.org/lkml/2013/10/3/279 >> >> [snip] >> >>> diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c >>> new file mode 100644 >>> index 0000000..1013109 >>> --- /dev/null >>> +++ b/arch/arm/mm/early_ioremap.c >>> @@ -0,0 +1,86 @@ >>> +/* >>> + * early_ioremap() support for ARM >>> + * >>> + * Based on existing support in arch/x86/mm/ioremap.c >>> + * >>> + * Restrictions: currently only functional before paging_init() >> >> Uhm, that's bad... This would explain why my earlycon code generates a >> fault as soon as something prints after paging_init(). I'd say this >> feature would be much more useful if mappings were carried over >> paging_init(), so that mapped devices are available later as well. >> >> I'll see if I can code this on top of your patch, but unfortunately it >> might end up with -ENOTIME. > > I have fixmap support that's needed for earlycon. Here is the branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git fixmap > > It is based on an earlier version of patchset and not on the latest > version from Leif. Unfortunately, I don't have more time to spend on > it ATM. Thanks Rob. I'll give it a try. Best regards, Tomasz ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 0/2] arm: add early_ioremap support 2014-07-09 9:39 [PATCH 0/2] arm: add early_ioremap support Leif Lindholm 2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm 2014-07-09 9:39 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm @ 2014-07-09 9:42 ` Russell King - ARM Linux 2014-07-09 9:58 ` Leif Lindholm 2014-07-09 9:47 ` Will Deacon 3 siblings, 1 reply; 17+ messages in thread From: Russell King - ARM Linux @ 2014-07-09 9:42 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 10:39:50AM +0100, Leif Lindholm wrote: > early_ioremap()/early_memremap() create temporary virtual mappings > in the fixmap region during boot time. Part of the support now exists > in core code, but depends on the generic fixmap support. Does this mean that the changes upon which this patch depends are already merged in mainline, or are they queued in some other tree? Thanks. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 0/2] arm: add early_ioremap support 2014-07-09 9:42 ` [PATCH 0/2] " Russell King - ARM Linux @ 2014-07-09 9:58 ` Leif Lindholm 0 siblings, 0 replies; 17+ messages in thread From: Leif Lindholm @ 2014-07-09 9:58 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 10:42:42AM +0100, Russell King - ARM Linux wrote: > On Wed, Jul 09, 2014 at 10:39:50AM +0100, Leif Lindholm wrote: > > early_ioremap()/early_memremap() create temporary virtual mappings > > in the fixmap region during boot time. Part of the support now exists > > in core code, but depends on the generic fixmap support. > > Does this mean that the changes upon which this patch depends are > already merged in mainline, or are they queued in some other tree? Yes, they went into 3.15. / Leif ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 0/2] arm: add early_ioremap support 2014-07-09 9:39 [PATCH 0/2] arm: add early_ioremap support Leif Lindholm ` (2 preceding siblings ...) 2014-07-09 9:42 ` [PATCH 0/2] " Russell King - ARM Linux @ 2014-07-09 9:47 ` Will Deacon 2014-07-09 10:02 ` Leif Lindholm 3 siblings, 1 reply; 17+ messages in thread From: Will Deacon @ 2014-07-09 9:47 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 10:39:50AM +0100, Leif Lindholm wrote: > early_ioremap()/early_memremap() create temporary virtual mappings > in the fixmap region during boot time. Part of the support now exists > in core code, but depends on the generic fixmap support. > > This set converts arm to use the generic fixmap support, and adds the > architecture-specific part of early_ioremap support. > > The fixmap/kmap changes in 3.15 complicated things slightly compared > to previous iterations of these patches - this version works around > that by introducing local macros in arm/mm/highmem.c. > > Tested on TC2 and software models, with/without LPAE. > > Mark Salter (2): > arm: use generic fixmap.h > arm: add early_ioremap support Curious: why are you sending these patches instead of Mark? Will ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 0/2] arm: add early_ioremap support 2014-07-09 9:47 ` Will Deacon @ 2014-07-09 10:02 ` Leif Lindholm 0 siblings, 0 replies; 17+ messages in thread From: Leif Lindholm @ 2014-07-09 10:02 UTC (permalink / raw) To: linux-arm-kernel On Wed, Jul 09, 2014 at 10:47:30AM +0100, Will Deacon wrote: > On Wed, Jul 09, 2014 at 10:39:50AM +0100, Leif Lindholm wrote: > > early_ioremap()/early_memremap() create temporary virtual mappings > > in the fixmap region during boot time. Part of the support now exists > > in core code, but depends on the generic fixmap support. > > > > This set converts arm to use the generic fixmap support, and adds the > > architecture-specific part of early_ioremap support. > > > > The fixmap/kmap changes in 3.15 complicated things slightly compared > > to previous iterations of these patches - this version works around > > that by introducing local macros in arm/mm/highmem.c. > > > > Tested on TC2 and software models, with/without LPAE. > > > > Mark Salter (2): > > arm: use generic fixmap.h > > arm: add early_ioremap support > > Curious: why are you sending these patches instead of Mark? Well, it used to form part of the larger UEFI patchset, which I'm still marshalling the 32-bit parts of (and which will follow later, but I will treat them separately from here on). Also, I did the hacky rework to Mark's original patches for the kmap changes. / Leif ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 0/2] arm: add early_ioremap() support @ 2013-06-25 17:46 Leif Lindholm 2013-06-25 17:46 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm 0 siblings, 1 reply; 17+ messages in thread From: Leif Lindholm @ 2013-06-25 17:46 UTC (permalink / raw) To: linux-arm-kernel x86 and ia64 have the early_ioremap()/early_iounmap() functions, which are useful for supporting things like UEFI, ACPI and SMBIOS, where configuration tables need to be parsed before proper memory management is available, regardless of highmem status. This patchset implements a restricted form of early_ioremap(), available before paging_init() only. Like the x86 code on which it is based, it (p)re-uses the fixmap regions for its virtual mapping range. Up to 7 simultaneous mappings of up to 128KB can be accommodated in the available fixmap space. Leif Lindholm (2): Documentation: arm: early_ioremap arm: add early_ioremap support Documentation/arm/00-INDEX | 2 + Documentation/arm/early_ioremap.txt | 12 ++ arch/arm/Kconfig | 7 + arch/arm/include/asm/fixmap.h | 31 +++- arch/arm/include/asm/io.h | 13 ++ arch/arm/kernel/setup.c | 3 + arch/arm/mm/Makefile | 1 + arch/arm/mm/early_ioremap.c | 273 +++++++++++++++++++++++++++++++++++ arch/arm/mm/mmu.c | 2 + 9 files changed, 342 insertions(+), 2 deletions(-) create mode 100644 Documentation/arm/early_ioremap.txt create mode 100644 arch/arm/mm/early_ioremap.c -- 1.7.10.4 ^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 2/2] arm: add early_ioremap support 2013-06-25 17:46 [PATCH 0/2] arm: add early_ioremap() support Leif Lindholm @ 2013-06-25 17:46 ` Leif Lindholm 0 siblings, 0 replies; 17+ messages in thread From: Leif Lindholm @ 2013-06-25 17:46 UTC (permalink / raw) To: linux-arm-kernel This patch adds support for early_ioremap, based on the existing mechanism in x86. Up to 7 regions of up to 128KB each can be temporarily mapped in before paging_init, regardless of later highmem status. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> --- arch/arm/Kconfig | 7 ++ arch/arm/include/asm/fixmap.h | 31 ++++- arch/arm/include/asm/io.h | 13 ++ arch/arm/kernel/setup.c | 3 + arch/arm/mm/Makefile | 1 + arch/arm/mm/early_ioremap.c | 273 +++++++++++++++++++++++++++++++++++++++++ arch/arm/mm/mmu.c | 2 + 7 files changed, 328 insertions(+), 2 deletions(-) create mode 100644 arch/arm/mm/early_ioremap.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 49d993c..bf8e55d 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1756,6 +1756,13 @@ config UACCESS_WITH_MEMCPY However, if the CPU data cache is using a write-allocate mode, this option is unlikely to provide any performance gain. +config EARLY_IOREMAP + depends on MMU + bool "Provide early_ioremap() support for kernel initialization." + help + Provides a mechanism for kernel initialisation code to temporarily + map, in a highmem-agnostic way, memory pages in before paging_init(). + config SECCOMP bool prompt "Enable seccomp to safely compute untrusted bytecode" diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h index bbae919..a2a5f50 100644 --- a/arch/arm/include/asm/fixmap.h +++ b/arch/arm/include/asm/fixmap.h @@ -1,6 +1,8 @@ #ifndef _ASM_FIXMAP_H #define _ASM_FIXMAP_H +#include <linux/bug.h> + /* * Nothing too fancy for now. * @@ -20,13 +22,38 @@ #define FIX_KMAP_BEGIN 0 #define FIX_KMAP_END (FIXADDR_SIZE >> PAGE_SHIFT) +/* + * 224 temporary boot-time mappings, used by early_ioremap(), + * before ioremap() is functional. + * + * (P)re-using the FIXADDR region, which is used for highmem + * later on, and statically aligned to 1MB. + */ +#define NR_FIX_BTMAPS 32 +#define FIX_BTMAPS_SLOTS 7 +#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) +#define FIX_BTMAP_BEGIN FIX_KMAP_BEGIN +#define FIX_BTMAP_END (FIX_KMAP_END - 1) + +#define clear_fixmap(idx) \ + __set_fixmap(idx, 0, __pgprot(0)) + #define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) #define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) extern void __this_fixmap_does_not_exist(void); -static inline unsigned long fix_to_virt(const unsigned int idx) +static __always_inline unsigned long fix_to_virt(const unsigned int idx) { + /* + * this branch gets completely eliminated after inlining, + * except when someone tries to use fixaddr indices in an + * illegal way. (such as mixing up address types or using + * out-of-range indices). + * + * If it doesn't get removed, the linker will complain + * loudly with a reasonably clear error message.. + */ if (idx >= FIX_KMAP_END) __this_fixmap_does_not_exist(); return __fix_to_virt(idx); @@ -38,4 +65,4 @@ static inline unsigned int virt_to_fix(const unsigned long vaddr) return __virt_to_fix(vaddr); } -#endif +#endif /* _ASM_FIXMAP_H */ diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index 652b560..c8866e3 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -397,5 +397,18 @@ extern int devmem_is_allowed(unsigned long pfn); extern void register_isa_ports(unsigned int mmio, unsigned int io, unsigned int io_shift); +/* + * early_ioremap() and early_iounmap() are for temporary early boot-time + * mappings, before the real ioremap() is functional. + * A boot-time mapping is currently limited to at most 16 pages. + * + * This is all squashed by paging_init(). + */ +extern void early_ioremap_init(void); +extern void early_ioremap_reset(void); +extern void __iomem *early_ioremap(resource_size_t phys_addr, + unsigned long size); +extern void early_iounmap(void __iomem *addr, unsigned long size); + #endif /* __KERNEL__ */ #endif /* __ASM_ARM_IO_H */ diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 1522c7a..290c561 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -36,6 +36,7 @@ #include <asm/cpu.h> #include <asm/cputype.h> #include <asm/elf.h> +#include <asm/io.h> #include <asm/procinfo.h> #include <asm/sections.h> #include <asm/setup.h> @@ -783,6 +784,8 @@ void __init setup_arch(char **cmdline_p) parse_early_param(); + early_ioremap_init(); + sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL); sanity_check_meminfo(); arm_memblock_init(&meminfo, mdesc); diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 9e51be9..ae2c477 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -15,6 +15,7 @@ endif obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o +obj-$(CONFIG_EARLY_IOREMAP) += early_ioremap.o obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_CPU_ABRT_NOMMU) += abort-nommu.o diff --git a/arch/arm/mm/early_ioremap.c b/arch/arm/mm/early_ioremap.c new file mode 100644 index 0000000..b14f58b --- /dev/null +++ b/arch/arm/mm/early_ioremap.c @@ -0,0 +1,273 @@ +/* + * early_ioremap() support for ARM + * + * Based on existing support in arch/x86/mm/ioremap.c + * + * Restrictions: currently only functional before paging_init() + */ + +#include <linux/init.h> +#include <linux/io.h> + +#include <asm/fixmap.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +#include <asm/mach/map.h> + +static int __initdata early_ioremap_debug; + +static int __init early_ioremap_debug_setup(char *str) +{ + early_ioremap_debug = 1; + + return 0; +} +early_param("early_ioremap_debug", early_ioremap_debug_setup); + +static pte_t __initdata bm_pte[PTRS_PER_PTE] __aligned(PTRS_PER_PTE * sizeof(pte_t)); +static __initdata int after_paging_init; + +static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) +{ + unsigned int index = pgd_index(addr); + pgd_t *pgd = cpu_get_pgd() + index; + pud_t *pud = pud_offset(pgd, addr); + pmd_t *pmd = pmd_offset(pud, addr); + + return pmd; +} + +static inline pte_t * __init early_ioremap_pte(unsigned long addr) +{ + return &bm_pte[pte_index(addr)]; +} + +static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata; + +void __init early_ioremap_init(void) +{ + pmd_t *pmd; + int i; + u64 desc; + + if (early_ioremap_debug) + pr_info("early_ioremap_init()\n"); + + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { + slot_virt[i] = __fix_to_virt(FIX_BTMAP_BEGIN + NR_FIX_BTMAPS*i); + if (early_ioremap_debug) + pr_info(" %lu byte slot @ 0x%08x\n", + NR_FIX_BTMAPS * PAGE_SIZE, (u32)slot_virt[i]); + } + + pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); + desc = *pmd; + memset(bm_pte, 0, sizeof(bm_pte)); + + pmd_populate_kernel(NULL, pmd, bm_pte); + desc = *pmd; + + BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) + != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); + + if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) { + WARN_ON(1); + pr_warn("pmd %p != %p\n", + pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))); + pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", + fix_to_virt(FIX_BTMAP_BEGIN)); + pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", + fix_to_virt(FIX_BTMAP_END)); + pr_warn("FIX_BTMAP_END: %lu\n", FIX_BTMAP_END); + pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); + } +} + +void __init early_ioremap_reset(void) +{ + after_paging_init = 1; +} + +static void __init __early_set_fixmap(unsigned long idx, + phys_addr_t phys, pgprot_t flags) +{ + unsigned long addr = __fix_to_virt(idx); + pte_t *pte; + u64 desc; + + if (idx >= FIX_KMAP_END) { + BUG(); + return; + } + pte = early_ioremap_pte(addr); + + if (pgprot_val(flags)) + set_pte_at(NULL, 0xfff00000, pte, + pfn_pte(phys >> PAGE_SHIFT, flags)); + else + pte_clear(NULL, addr, pte); + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + desc = *pte; +} + +static inline void __init early_set_fixmap(unsigned long idx, + phys_addr_t phys, pgprot_t prot) +{ + __early_set_fixmap(idx, phys, prot); +} + +static inline void __init early_clear_fixmap(unsigned long idx) +{ + __early_set_fixmap(idx, 0, __pgprot(0)); +} + +static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata; +static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata; + +static void __init __iomem * +__early_ioremap(resource_size_t phys_addr, unsigned long size, pgprot_t prot) +{ + unsigned long offset; + resource_size_t last_addr; + unsigned int nrpages; + unsigned long idx; + int i, slot; + + slot = -1; + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { + if (!prev_map[i]) { + slot = i; + break; + } + } + + if (slot < 0) { + pr_info("early_iomap(%08llx, %08lx) not found slot\n", + (u64)phys_addr, size); + WARN_ON(1); + return NULL; + } + + if (early_ioremap_debug) { + pr_info("early_ioremap(%08llx, %08lx) [%d] => ", + (u64)phys_addr, size, slot); + } + + /* Don't allow wraparound or zero size */ + last_addr = phys_addr + size - 1; + if (!size || last_addr < phys_addr) { + WARN_ON(1); + return NULL; + } + + prev_size[slot] = size; + /* + * Mappings have to be page-aligned + */ + offset = phys_addr & ~PAGE_MASK; + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(last_addr + 1) - phys_addr; + + /* + * Mappings have to fit in the FIX_BTMAP area. + */ + nrpages = size >> PAGE_SHIFT; + if (nrpages > NR_FIX_BTMAPS) { + WARN_ON(1); + return NULL; + } + + /* + * Ok, go for it.. + */ + idx = FIX_BTMAP_BEGIN + slot * NR_FIX_BTMAPS; + while (nrpages > 0) { + early_set_fixmap(idx, phys_addr, prot); + phys_addr += PAGE_SIZE; + idx++; + --nrpages; + } + if (early_ioremap_debug) + pr_cont("%08lx + %08lx\n", offset, slot_virt[slot]); + + prev_map[slot] = (void __iomem *)(offset + slot_virt[slot]); + return prev_map[slot]; +} + +/* Remap an IO device */ +void __init __iomem * +early_ioremap(resource_size_t phys_addr, unsigned long size) +{ + unsigned long prot; + + if (after_paging_init) { + WARN_ON(1); + return NULL; + } + + /* + * PAGE_KERNEL depends on not-yet-initialised variables. + * We don't care about coherency or executability of early_ioremap + * pages anyway. + */ + prot = L_PTE_YOUNG | L_PTE_PRESENT | L_PTE_MT_DEV_NONSHARED; + return __early_ioremap(phys_addr, size, prot); +} + + +void __init early_iounmap(void __iomem *addr, unsigned long size) +{ + unsigned long virt_addr; + unsigned long offset; + unsigned int nrpages; + unsigned long idx; + int i, slot; + + if (after_paging_init) { + WARN_ON(1); + return; + } + + slot = -1; + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { + if (prev_map[i] == addr) { + slot = i; + break; + } + } + + if (slot < 0) { + pr_info("early_iounmap(%p, %08lx) not found slot\n", + addr, size); + WARN_ON(1); + return; + } + + if (prev_size[slot] != size) { + pr_info("early_iounmap(%p, %08lx) [%d] size not consistent %08lx\n", + addr, size, slot, prev_size[slot]); + WARN_ON(1); + return; + } + + if (early_ioremap_debug) + pr_info("early_iounmap(%p, %08lx) [%d]\n", addr, size, slot); + + virt_addr = (unsigned long)addr; + if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)) { + WARN_ON(1); + return; + } + offset = virt_addr & ~PAGE_MASK; + nrpages = PAGE_ALIGN(offset + size) >> PAGE_SHIFT; + + idx = FIX_BTMAP_BEGIN + slot * NR_FIX_BTMAPS; + while (nrpages > 0) { + early_clear_fixmap(idx); + idx++; + --nrpages; + } + prev_map[slot] = NULL; +} diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index e0d8565..c953b20 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -28,6 +28,7 @@ #include <asm/highmem.h> #include <asm/system_info.h> #include <asm/traps.h> +#include <asm/io.h> #include <asm/mach/arch.h> #include <asm/mach/map.h> @@ -1306,4 +1307,5 @@ void __init paging_init(struct machine_desc *mdesc) empty_zero_page = virt_to_page(zero_page); __flush_dcache_page(NULL, empty_zero_page); + early_ioremap_reset(); } -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 17+ messages in thread
end of thread, other threads:[~2014-07-25 19:56 UTC | newest] Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-07-09 9:39 [PATCH 0/2] arm: add early_ioremap support Leif Lindholm 2014-07-09 9:39 ` [PATCH 1/2] arm: use generic fixmap.h Leif Lindholm 2014-07-09 20:49 ` Mark Salter 2014-07-18 14:33 ` Leif Lindholm 2014-07-25 19:56 ` Kees Cook 2014-07-22 16:39 ` Tomasz Figa 2014-07-09 9:39 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm 2014-07-09 9:49 ` Russell King - ARM Linux 2014-07-09 11:48 ` Leif Lindholm 2014-07-22 16:48 ` Tomasz Figa 2014-07-22 17:11 ` Rob Herring 2014-07-22 17:27 ` Tomasz Figa 2014-07-09 9:42 ` [PATCH 0/2] " Russell King - ARM Linux 2014-07-09 9:58 ` Leif Lindholm 2014-07-09 9:47 ` Will Deacon 2014-07-09 10:02 ` Leif Lindholm -- strict thread matches above, loose matches on Subject: below -- 2013-06-25 17:46 [PATCH 0/2] arm: add early_ioremap() support Leif Lindholm 2013-06-25 17:46 ` [PATCH 2/2] arm: add early_ioremap support Leif Lindholm
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