Commit 1af1e8a3 authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: move fixmap and kmap just above the KSEG 



The virtual address space between the page table and the VMALLOC region
is big enough to host KASAN shadow map and there's enough space between
the VMALLOC area and KSEG for the fixmap and kmap.
Move fixmap and kmap to the gap between VMALLOC area and KSEG, just
above the KSEG. Reorder entries in the kernel memory layout printing
code. Drop duplicate PGTABLE_START definition, use
XCHAL_PAGE_TABLE_VADDR instead.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent d4e337fe

Documentation/xtensa/mmu.txt

+36 −36
Original line number Diff line number Diff line
@@ -69,19 +69,8 @@ Default MMUv2-compatible layout. 
| Userspace        |                           0x00000000  TASK_SIZE

+------------------+                           0x40000000

+------------------+

| Page table       |                           0x80000000

+------------------+                           0x80400000

| Page table       |  XCHAL_PAGE_TABLE_VADDR   0x80000000  XCHAL_PAGE_TABLE_SIZE

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0xbffff000

+------------------+

| VMALLOC area     |  VMALLOC_START            0xc0000000  128MB - 64KB

+------------------+  VMALLOC_END
@@ -92,6 +81,17 @@ Default MMUv2-compatible layout. 
| remap area 2     |

+------------------+

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0xcffff000

+------------------+

| Cached KSEG      |  XCHAL_KSEG_CACHED_VADDR  0xd0000000  128MB

+------------------+

| Uncached KSEG    |  XCHAL_KSEG_BYPASS_VADDR  0xd8000000  128MB
@@ -109,19 +109,8 @@ Default MMUv2-compatible layout. 
| Userspace        |                           0x00000000  TASK_SIZE

+------------------+                           0x40000000

+------------------+

| Page table       |                           0x80000000

+------------------+                           0x80400000

| Page table       |  XCHAL_PAGE_TABLE_VADDR   0x80000000  XCHAL_PAGE_TABLE_SIZE

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0x9ffff000

+------------------+

| VMALLOC area     |  VMALLOC_START            0xa0000000  128MB - 64KB

+------------------+  VMALLOC_END
@@ -132,6 +121,17 @@ Default MMUv2-compatible layout. 
| remap area 2     |

+------------------+

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0xaffff000

+------------------+

| Cached KSEG      |  XCHAL_KSEG_CACHED_VADDR  0xb0000000  256MB

+------------------+

| Uncached KSEG    |  XCHAL_KSEG_BYPASS_VADDR  0xc0000000  256MB
@@ -150,19 +150,8 @@ Default MMUv2-compatible layout. 
| Userspace        |                           0x00000000  TASK_SIZE

+------------------+                           0x40000000

+------------------+

| Page table       |                           0x80000000

+------------------+                           0x80400000

| Page table       |  XCHAL_PAGE_TABLE_VADDR   0x80000000  XCHAL_PAGE_TABLE_SIZE

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0x8ffff000

+------------------+

| VMALLOC area     |  VMALLOC_START            0x90000000  128MB - 64KB

+------------------+  VMALLOC_END
@@ -173,6 +162,17 @@ Default MMUv2-compatible layout. 
| remap area 2     |

+------------------+

+------------------+

| KMAP area        |  PKMAP_BASE                           PTRS_PER_PTE *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

|                  |                                       (4MB * DCACHE_N_COLORS)

+------------------+

| Atomic KMAP area |  FIXADDR_START                        KM_TYPE_NR *

|                  |                                       NR_CPUS *

|                  |                                       DCACHE_N_COLORS *

|                  |                                       PAGE_SIZE

+------------------+  FIXADDR_TOP              0x9ffff000

+------------------+

| Cached KSEG      |  XCHAL_KSEG_CACHED_VADDR  0xa0000000  512MB

+------------------+

| Uncached KSEG    |  XCHAL_KSEG_BYPASS_VADDR  0xc0000000  512MB

arch/xtensa/include/asm/fixmap.h

+2 −2
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ enum fixed_addresses { 
	__end_of_fixed_addresses

};



#define FIXADDR_TOP     (VMALLOC_START - PAGE_SIZE)

#define FIXADDR_TOP     (XCHAL_KSEG_CACHED_VADDR - PAGE_SIZE)

#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)

#define FIXADDR_START	((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK)
@@ -63,7 +63,7 @@ static __always_inline unsigned long fix_to_virt(const unsigned int idx) 
	 * table.

	 */

	BUILD_BUG_ON(FIXADDR_START <

		     XCHAL_PAGE_TABLE_VADDR + XCHAL_PAGE_TABLE_SIZE);

		     TLBTEMP_BASE_1 + TLBTEMP_SIZE);

	BUILD_BUG_ON(idx >= __end_of_fixed_addresses);

	return __fix_to_virt(idx);

}

arch/xtensa/include/asm/highmem.h

+1 −1
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ static inline void *kmap(struct page *page) 
	 * page table.

	 */

	BUILD_BUG_ON(PKMAP_BASE <

		     XCHAL_PAGE_TABLE_VADDR + XCHAL_PAGE_TABLE_SIZE);

		     TLBTEMP_BASE_1 + TLBTEMP_SIZE);

	BUG_ON(in_interrupt());

	if (!PageHighMem(page))

		return page_address(page);

arch/xtensa/include/asm/page.h

+0 −2
Original line number Diff line number Diff line
@@ -36,8 +36,6 @@ 
#define MAX_LOW_PFN	PHYS_PFN(0xfffffffful)

#endif



#define PGTABLE_START	0x80000000



/*

 * Cache aliasing:

 *

arch/xtensa/mm/init.c

+6 −6
Original line number Diff line number Diff line
@@ -100,23 +100,23 @@ void __init mem_init(void) 


	mem_init_print_info(NULL);

	pr_info("virtual kernel memory layout:\n"

#ifdef CONFIG_MMU

		"    vmalloc : 0x%08lx - 0x%08lx  (%5lu MB)\n"

#endif

#ifdef CONFIG_HIGHMEM

		"    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"

		"    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"

#endif

#ifdef CONFIG_MMU

		"    vmalloc : 0x%08lx - 0x%08lx  (%5lu MB)\n"

#endif

		"    lowmem  : 0x%08lx - 0x%08lx  (%5lu MB)\n",

#ifdef CONFIG_MMU

		VMALLOC_START, VMALLOC_END,

		(VMALLOC_END - VMALLOC_START) >> 20,

#ifdef CONFIG_HIGHMEM

		PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,

		(LAST_PKMAP*PAGE_SIZE) >> 10,

		FIXADDR_START, FIXADDR_TOP,

		(FIXADDR_TOP - FIXADDR_START) >> 10,

#endif

#ifdef CONFIG_MMU

		VMALLOC_START, VMALLOC_END,

		(VMALLOC_END - VMALLOC_START) >> 20,

		PAGE_OFFSET, PAGE_OFFSET +

		(max_low_pfn - min_low_pfn) * PAGE_SIZE,

#else

CRA Git | Maintained and supported by SUSTech CRA and CCSE