diff options
author | Ingo Molnar <mingo@kernel.org> | 2020-01-10 18:53:14 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2020-01-10 18:53:14 +0100 |
commit | 57ad87ddce79b6d54f8e442d0ecf4b5bbe8c5a9e (patch) | |
tree | eaa43171e82737e8b33239e2e9bc3b4de67b7ddd /arch/x86/mm | |
parent | 02df083201272c0c2e061b18d9c20635974abf6d (diff) | |
parent | 186525bd6b83efc592672e2d6185e4d7c810d2b4 (diff) |
Merge branch 'x86/mm' into efi/core, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/mm')
-rw-r--r-- | arch/x86/mm/Makefile | 8 | ||||
-rw-r--r-- | arch/x86/mm/fault.c | 1 | ||||
-rw-r--r-- | arch/x86/mm/init_32.c | 1 | ||||
-rw-r--r-- | arch/x86/mm/iomap_32.c | 6 | ||||
-rw-r--r-- | arch/x86/mm/ioremap.c | 12 | ||||
-rw-r--r-- | arch/x86/mm/pat/Makefile | 5 | ||||
-rw-r--r-- | arch/x86/mm/pat/cpa-test.c (renamed from arch/x86/mm/pageattr-test.c) | 0 | ||||
-rw-r--r-- | arch/x86/mm/pat/memtype.c (renamed from arch/x86/mm/pat.c) | 203 | ||||
-rw-r--r-- | arch/x86/mm/pat/memtype.h (renamed from arch/x86/mm/pat_internal.h) | 12 | ||||
-rw-r--r-- | arch/x86/mm/pat/memtype_interval.c | 194 | ||||
-rw-r--r-- | arch/x86/mm/pat/set_memory.c (renamed from arch/x86/mm/pageattr.c) | 24 | ||||
-rw-r--r-- | arch/x86/mm/pat_interval.c | 185 | ||||
-rw-r--r-- | arch/x86/mm/pgtable_32.c | 1 | ||||
-rw-r--r-- | arch/x86/mm/physaddr.c | 1 |
14 files changed, 353 insertions, 300 deletions
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index 3b89c201ac26..345848f270e3 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -12,8 +12,10 @@ CFLAGS_REMOVE_mem_encrypt.o = -pg CFLAGS_REMOVE_mem_encrypt_identity.o = -pg endif -obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \ - pat.o pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o +obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \ + pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o + +obj-y += pat/ # Make sure __phys_addr has no stackprotector nostackp := $(call cc-option, -fno-stack-protector) @@ -23,8 +25,6 @@ CFLAGS_mem_encrypt_identity.o := $(nostackp) CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace -obj-$(CONFIG_X86_PAT) += pat_interval.o - obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 304d31d8cbbc..c9c8523a3a48 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -29,6 +29,7 @@ #include <asm/efi.h> /* efi_recover_from_page_fault()*/ #include <asm/desc.h> /* store_idt(), ... */ #include <asm/cpu_entry_area.h> /* exception stack */ +#include <asm/pgtable_areas.h> /* VMALLOC_START, ... */ #define CREATE_TRACE_POINTS #include <asm/trace/exceptions.h> diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 0a74407ef92e..8d29ae8d3eb7 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -52,6 +52,7 @@ #include <asm/page_types.h> #include <asm/cpu_entry_area.h> #include <asm/init.h> +#include <asm/pgtable_areas.h> #include "mm_internal.h" diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c index 6748b4c2baff..f60398aeb644 100644 --- a/arch/x86/mm/iomap_32.c +++ b/arch/x86/mm/iomap_32.c @@ -4,7 +4,7 @@ */ #include <asm/iomap.h> -#include <asm/pat.h> +#include <asm/memtype.h> #include <linux/export.h> #include <linux/highmem.h> @@ -26,7 +26,7 @@ int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot) if (!is_io_mapping_possible(base, size)) return -EINVAL; - ret = io_reserve_memtype(base, base + size, &pcm); + ret = memtype_reserve_io(base, base + size, &pcm); if (ret) return ret; @@ -40,7 +40,7 @@ EXPORT_SYMBOL_GPL(iomap_create_wc); void iomap_free(resource_size_t base, unsigned long size) { - io_free_memtype(base, base + size); + memtype_free_io(base, base + size); } EXPORT_SYMBOL_GPL(iomap_free); diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index b3a2936377b5..44e4beb4239f 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -24,7 +24,7 @@ #include <asm/pgtable.h> #include <asm/tlbflush.h> #include <asm/pgalloc.h> -#include <asm/pat.h> +#include <asm/memtype.h> #include <asm/setup.h> #include "physaddr.h" @@ -196,10 +196,10 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size, phys_addr &= PHYSICAL_PAGE_MASK; size = PAGE_ALIGN(last_addr+1) - phys_addr; - retval = reserve_memtype(phys_addr, (u64)phys_addr + size, + retval = memtype_reserve(phys_addr, (u64)phys_addr + size, pcm, &new_pcm); if (retval) { - printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval); + printk(KERN_ERR "ioremap memtype_reserve failed %d\n", retval); return NULL; } @@ -255,7 +255,7 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size, area->phys_addr = phys_addr; vaddr = (unsigned long) area->addr; - if (kernel_map_sync_memtype(phys_addr, size, pcm)) + if (memtype_kernel_map_sync(phys_addr, size, pcm)) goto err_free_area; if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) @@ -275,7 +275,7 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size, err_free_area: free_vm_area(area); err_free_memtype: - free_memtype(phys_addr, phys_addr + size); + memtype_free(phys_addr, phys_addr + size); return NULL; } @@ -451,7 +451,7 @@ void iounmap(volatile void __iomem *addr) return; } - free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p)); + memtype_free(p->phys_addr, p->phys_addr + get_vm_area_size(p)); /* Finally remove it */ o = remove_vm_area((void __force *)addr); diff --git a/arch/x86/mm/pat/Makefile b/arch/x86/mm/pat/Makefile new file mode 100644 index 000000000000..ea464c995161 --- /dev/null +++ b/arch/x86/mm/pat/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-y := set_memory.o memtype.o + +obj-$(CONFIG_X86_PAT) += memtype_interval.o diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pat/cpa-test.c index facce271e8b9..facce271e8b9 100644 --- a/arch/x86/mm/pageattr-test.c +++ b/arch/x86/mm/pat/cpa-test.c diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat/memtype.c index 2d758e19ef22..394be8611748 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat/memtype.c @@ -1,11 +1,34 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Handle caching attributes in page tables (PAT) + * Page Attribute Table (PAT) support: handle memory caching attributes in page tables. * * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> * Suresh B Siddha <suresh.b.siddha@intel.com> * * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen. + * + * Basic principles: + * + * PAT is a CPU feature supported by all modern x86 CPUs, to allow the firmware and + * the kernel to set one of a handful of 'caching type' attributes for physical + * memory ranges: uncached, write-combining, write-through, write-protected, + * and the most commonly used and default attribute: write-back caching. + * + * PAT support supercedes and augments MTRR support in a compatible fashion: MTRR is + * a hardware interface to enumerate a limited number of physical memory ranges + * and set their caching attributes explicitly, programmed into the CPU via MSRs. + * Even modern CPUs have MTRRs enabled - but these are typically not touched + * by the kernel or by user-space (such as the X server), we rely on PAT for any + * additional cache attribute logic. + * + * PAT doesn't work via explicit memory ranges, but uses page table entries to add + * cache attribute information to the mapped memory range: there's 3 bits used, + * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT), with the 8 possible values mapped by the + * CPU to actual cache attributes via an MSR loaded into the CPU (MSR_IA32_CR_PAT). + * + * ( There's a metric ton of finer details, such as compatibility with CPU quirks + * that only support 4 types of PAT entries, and interaction with MTRRs, see + * below for details. ) */ #include <linux/seq_file.h> @@ -29,44 +52,48 @@ #include <asm/mtrr.h> #include <asm/page.h> #include <asm/msr.h> -#include <asm/pat.h> +#include <asm/memtype.h> #include <asm/io.h> -#include "pat_internal.h" -#include "mm_internal.h" +#include "memtype.h" +#include "../mm_internal.h" #undef pr_fmt #define pr_fmt(fmt) "" fmt -static bool __read_mostly boot_cpu_done; +static bool __read_mostly pat_bp_initialized; static bool __read_mostly pat_disabled = !IS_ENABLED(CONFIG_X86_PAT); -static bool __read_mostly pat_initialized; -static bool __read_mostly init_cm_done; +static bool __read_mostly pat_bp_enabled; +static bool __read_mostly pat_cm_initialized; -void pat_disable(const char *reason) +/* + * PAT support is enabled by default, but can be disabled for + * various user-requested or hardware-forced reasons: + */ +void pat_disable(const char *msg_reason) { if (pat_disabled) return; - if (boot_cpu_done) { + if (pat_bp_initialized) { WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n"); return; } pat_disabled = true; - pr_info("x86/PAT: %s\n", reason); + pr_info("x86/PAT: %s\n", msg_reason); } static int __init nopat(char *str) { - pat_disable("PAT support disabled."); + pat_disable("PAT support disabled via boot option."); return 0; } early_param("nopat", nopat); bool pat_enabled(void) { - return pat_initialized; + return pat_bp_enabled; } EXPORT_SYMBOL_GPL(pat_enabled); @@ -197,6 +224,8 @@ static void __init_cache_modes(u64 pat) char pat_msg[33]; int i; + WARN_ON_ONCE(pat_cm_initialized); + pat_msg[32] = 0; for (i = 7; i >= 0; i--) { cache = pat_get_cache_mode((pat >> (i * 8)) & 7, @@ -205,28 +234,28 @@ static void __init_cache_modes(u64 pat) } pr_info("x86/PAT: Configuration [0-7]: %s\n", pat_msg); - init_cm_done = true; + pat_cm_initialized = true; } #define PAT(x, y) ((u64)PAT_ ## y << ((x)*8)) -static void pat_bsp_init(u64 pat) +static void pat_bp_init(u64 pat) { u64 tmp_pat; if (!boot_cpu_has(X86_FEATURE_PAT)) { - pat_disable("PAT not supported by CPU."); + pat_disable("PAT not supported by the CPU."); return; } rdmsrl(MSR_IA32_CR_PAT, tmp_pat); if (!tmp_pat) { - pat_disable("PAT MSR is 0, disabled."); + pat_disable("PAT support disabled by the firmware."); return; } wrmsrl(MSR_IA32_CR_PAT, pat); - pat_initialized = true; + pat_bp_enabled = true; __init_cache_modes(pat); } @@ -248,7 +277,7 @@ void init_cache_modes(void) { u64 pat = 0; - if (init_cm_done) + if (pat_cm_initialized) return; if (boot_cpu_has(X86_FEATURE_PAT)) { @@ -291,7 +320,7 @@ void init_cache_modes(void) } /** - * pat_init - Initialize PAT MSR and PAT table + * pat_init - Initialize the PAT MSR and PAT table on the current CPU * * This function initializes PAT MSR and PAT table with an OS-defined value * to enable additional cache attributes, WC, WT and WP. @@ -305,6 +334,10 @@ void pat_init(void) u64 pat; struct cpuinfo_x86 *c = &boot_cpu_data; +#ifndef CONFIG_X86_PAT + pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n"); +#endif + if (pat_disabled) return; @@ -364,9 +397,9 @@ void pat_init(void) PAT(4, WB) | PAT(5, WP) | PAT(6, UC_MINUS) | PAT(7, WT); } - if (!boot_cpu_done) { - pat_bsp_init(pat); - boot_cpu_done = true; + if (!pat_bp_initialized) { + pat_bp_init(pat); + pat_bp_initialized = true; } else { pat_ap_init(pat); } @@ -542,10 +575,10 @@ static u64 sanitize_phys(u64 address) * available type in new_type in case of no error. In case of any error * it will return a negative return value. */ -int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type, +int memtype_reserve(u64 start, u64 end, enum page_cache_mode req_type, enum page_cache_mode *new_type) { - struct memtype *new; + struct memtype *entry_new; enum page_cache_mode actual_type; int is_range_ram; int err = 0; @@ -593,22 +626,22 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type, return -EINVAL; } - new = kzalloc(sizeof(struct memtype), GFP_KERNEL); - if (!new) + entry_new = kzalloc(sizeof(struct memtype), GFP_KERNEL); + if (!entry_new) return -ENOMEM; - new->start = start; - new->end = end; - new->type = actual_type; + entry_new->start = start; + entry_new->end = end; + entry_new->type = actual_type; spin_lock(&memtype_lock); - err = memtype_check_insert(new, new_type); + err = memtype_check_insert(entry_new, new_type); if (err) { - pr_info("x86/PAT: reserve_memtype failed [mem %#010Lx-%#010Lx], track %s, req %s\n", + pr_info("x86/PAT: memtype_reserve failed [mem %#010Lx-%#010Lx], track %s, req %s\n", start, end - 1, - cattr_name(new->type), cattr_name(req_type)); - kfree(new); + cattr_name(entry_new->type), cattr_name(req_type)); + kfree(entry_new); spin_unlock(&memtype_lock); return err; @@ -616,18 +649,17 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type, spin_unlock(&memtype_lock); - dprintk("reserve_memtype added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n", - start, end - 1, cattr_name(new->type), cattr_name(req_type), + dprintk("memtype_reserve added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n", + start, end - 1, cattr_name(entry_new->type), cattr_name(req_type), new_type ? cattr_name(*new_type) : "-"); return err; } -int free_memtype(u64 start, u64 end) +int memtype_free(u64 start, u64 end) { - int err = -EINVAL; int is_range_ram; - struct memtype *entry; + struct memtype *entry_old; if (!pat_enabled()) return 0; @@ -640,28 +672,24 @@ int free_memtype(u64 start, u64 end) return 0; is_range_ram = pat_pagerange_is_ram(start, end); - if (is_range_ram == 1) { - - err = free_ram_pages_type(start, end); - - return err; - } else if (is_range_ram < 0) { + if (is_range_ram == 1) + return free_ram_pages_type(start, end); + if (is_range_ram < 0) return -EINVAL; - } spin_lock(&memtype_lock); - entry = memtype_erase(start, end); + entry_old = memtype_erase(start, end); spin_unlock(&memtype_lock); - if (IS_ERR(entry)) { + if (IS_ERR(entry_old)) { pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n", current->comm, current->pid, start, end - 1); return -EINVAL; } - kfree(entry); + kfree(entry_old); - dprintk("free_memtype request [mem %#010Lx-%#010Lx]\n", start, end - 1); + dprintk("memtype_free request [mem %#010Lx-%#010Lx]\n", start, end - 1); return 0; } @@ -700,6 +728,7 @@ static enum page_cache_mode lookup_memtype(u64 paddr) rettype = _PAGE_CACHE_MODE_UC_MINUS; spin_unlock(&memtype_lock); + return rettype; } @@ -723,7 +752,7 @@ bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn) EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr); /** - * io_reserve_memtype - Request a memory type mapping for a region of memory + * memtype_reserve_io - Request a memory type mapping for a region of memory * @start: start (physical address) of the region * @end: end (physical address) of the region * @type: A pointer to memtype, with requested type. On success, requested @@ -732,7 +761,7 @@ EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr); * On success, returns 0 * On failure, returns non-zero */ -int io_reserve_memtype(resource_size_t start, resource_size_t end, +int memtype_reserve_io(resource_size_t start, resource_size_t end, enum page_cache_mode *type) { resource_size_t size = end - start; @@ -742,47 +771,47 @@ int io_reserve_memtype(resource_size_t start, resource_size_t end, WARN_ON_ONCE(iomem_map_sanity_check(start, size)); - ret = reserve_memtype(start, end, req_type, &new_type); + ret = memtype_reserve(start, end, req_type, &new_type); if (ret) goto out_err; if (!is_new_memtype_allowed(start, size, req_type, new_type)) goto out_free; - if (kernel_map_sync_memtype(start, size, new_type) < 0) + if (memtype_kernel_map_sync(start, size, new_type) < 0) goto out_free; *type = new_type; return 0; out_free: - free_memtype(start, end); + memtype_free(start, end); ret = -EBUSY; out_err: return ret; } /** - * io_free_memtype - Release a memory type mapping for a region of memory + * memtype_free_io - Release a memory type mapping for a region of memory * @start: start (physical address) of the region * @end: end (physical address) of the region */ -void io_free_memtype(resource_size_t start, resource_size_t end) +void memtype_free_io(resource_size_t start, resource_size_t end) { - free_memtype(start, end); + memtype_free(start, end); } int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size) { enum page_cache_mode type = _PAGE_CACHE_MODE_WC; - return io_reserve_memtype(start, start + size, &type); + return memtype_reserve_io(start, start + size, &type); } EXPORT_SYMBOL(arch_io_reserve_memtype_wc); void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size) { - io_free_memtype(start, start + size); + memtype_free_io(start, start + size); } EXPORT_SYMBOL(arch_io_free_memtype_wc); @@ -839,10 +868,10 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, } /* - * Change the memory type for the physial address range in kernel identity + * Change the memory type for the physical address range in kernel identity * mapping space if that range is a part of identity map. */ -int kernel_map_sync_memtype(u64 base, unsigned long size, +int memtype_kernel_map_sync(u64 base, unsigned long size, enum page_cache_mode pcm) { unsigned long id_sz; @@ -851,15 +880,14 @@ int kernel_map_sync_memtype(u64 base, unsigned long size, return 0; /* - * some areas in the middle of the kernel identity range - * are not mapped, like the PCI space. + * Some areas in the middle of the kernel identity range + * are not mapped, for example the PCI space. */ if (!page_is_ram(base >> PAGE_SHIFT)) return 0; id_sz = (__pa(high_memory-1) <= base + size) ? - __pa(high_memory) - base : - size; + __pa(high_memory) - base : size; if (ioremap_change_attr((unsigned long)__va(base), id_sz, pcm) < 0) { pr_info("x86/PAT: %s:%d ioremap_change_attr failed %s for [mem %#010Lx-%#010Lx]\n", @@ -873,7 +901,7 @@ int kernel_map_sync_memtype(u64 base, unsigned long size, /* * Internal interface to reserve a range of physical memory with prot. - * Reserved non RAM regions only and after successful reserve_memtype, + * Reserved non RAM regions only and after successful memtype_reserve, * this func also keeps identity mapping (if any) in sync with this new prot. */ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot, @@ -910,14 +938,14 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot, return 0; } - ret = reserve_memtype(paddr, paddr + size, want_pcm, &pcm); + ret = memtype_reserve(paddr, paddr + size, want_pcm, &pcm); if (ret) return ret; if (pcm != want_pcm) { if (strict_prot || !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) { - free_memtype(paddr, paddr + size); + memtype_free(paddr, paddr + size); pr_err("x86/PAT: %s:%d map pfn expected mapping type %s for [mem %#010Lx-%#010Lx], got %s\n", current->comm, current->pid, cattr_name(want_pcm), @@ -935,8 +963,8 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot, cachemode2protval(pcm)); } - if (kernel_map_sync_memtype(paddr, size, pcm) < 0) { - free_memtype(paddr, paddr + size); + if (memtype_kernel_map_sync(paddr, size, pcm) < 0) { + memtype_free(paddr, paddr + size); return -EINVAL; } return 0; @@ -952,7 +980,7 @@ static void free_pfn_range(u64 paddr, unsigned long size) is_ram = pat_pagerange_is_ram(paddr, paddr + size); if (is_ram == 0) - free_memtype(paddr, paddr + size); + memtype_free(paddr, paddr + size); } /* @@ -1099,25 +1127,30 @@ EXPORT_SYMBOL_GPL(pgprot_writethrough); #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) +/* + * We are allocating a temporary printout-entry to be passed + * between seq_start()/next() and seq_show(): + */ static struct memtype *memtype_get_idx(loff_t pos) { - struct memtype *print_entry; + struct memtype *entry_print; int ret; - print_entry = kzalloc(sizeof(struct memtype), GFP_KERNEL); - if (!print_entry) + entry_print = kzalloc(sizeof(struct memtype), GFP_KERNEL); + if (!entry_print) return NULL; spin_lock(&memtype_lock); - ret = memtype_copy_nth_element(print_entry, pos); + ret = memtype_copy_nth_element(entry_print, pos); spin_unlock(&memtype_lock); - if (!ret) { - return print_entry; - } else { - kfree(print_entry); + /* Free it on error: */ + if (ret) { + kfree(entry_print); return NULL; } + + return entry_print; } static void *memtype_seq_start(struct seq_file *seq, loff_t *pos) @@ -1142,11 +1175,14 @@ static void memtype_seq_stop(struct seq_file *seq, void *v) static int memtype_seq_show(struct seq_file *seq, void *v) { - struct memtype *print_entry = (struct memtype *)v; + struct memtype *entry_print = (struct memtype *)v; + + seq_printf(seq, "PAT: [mem 0x%016Lx-0x%016Lx] %s\n", + entry_print->start, + entry_print->end, + cattr_name(entry_print->type)); - seq_printf(seq, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry->type), - print_entry->start, print_entry->end); - kfree(print_entry); + kfree(entry_print); return 0; } @@ -1178,7 +1214,6 @@ static int __init pat_memtype_list_init(void) } return 0; } - late_initcall(pat_memtype_list_init); #endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */ diff --git a/arch/x86/mm/pat_internal.h b/arch/x86/mm/pat/memtype.h index 79a06684349e..cacecdbceb55 100644 --- a/arch/x86/mm/pat_internal.h +++ b/arch/x86/mm/pat/memtype.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ -#ifndef __PAT_INTERNAL_H_ -#define __PAT_INTERNAL_H_ +#ifndef __MEMTYPE_H_ +#define __MEMTYPE_H_ extern int pat_debug_enable; @@ -29,13 +29,13 @@ static inline char *cattr_name(enum page_cache_mode pcm) } #ifdef CONFIG_X86_PAT -extern int memtype_check_insert(struct memtype *new, +extern int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *new_type); extern struct memtype *memtype_erase(u64 start, u64 end); extern struct memtype *memtype_lookup(u64 addr); -extern int memtype_copy_nth_element(struct memtype *out, loff_t pos); +extern int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos); #else -static inline int memtype_check_insert(struct memtype *new, +static inline int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *new_type) { return 0; } static inline struct memtype *memtype_erase(u64 start, u64 end) @@ -46,4 +46,4 @@ static inline int memtype_copy_nth_element(struct memtype *out, loff_t pos) { return 0; } #endif -#endif /* __PAT_INTERNAL_H_ */ +#endif /* __MEMTYPE_H_ */ diff --git a/arch/x86/mm/pat/memtype_interval.c b/arch/x86/mm/pat/memtype_interval.c new file mode 100644 index 000000000000..a07e4882bf36 --- /dev/null +++ b/arch/x86/mm/pat/memtype_interval.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Handle caching attributes in page tables (PAT) + * + * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> + * Suresh B Siddha <suresh.b.siddha@intel.com> + * + * Interval tree used to store the PAT memory type reservations. + */ + +#include <linux/seq_file.h> +#include <linux/debugfs.h> +#include <linux/kernel.h> +#include <linux/interval_tree_generic.h> +#include <linux/sched.h> +#include <linux/gfp.h> + +#include <asm/pgtable.h> +#include <asm/memtype.h> + +#include "memtype.h" + +/* + * The memtype tree keeps track of memory type for specific + * physical memory areas. Without proper tracking, conflicting memory + * types in different mappings can cause CPU cache corruption. + * + * The tree is an interval tree (augmented rbtree) which tree is ordered + * by the starting address. The tree can contain multiple entries for + * different regions which overlap. All the aliases have the same + * cache attributes of course, as enforced by the PAT logic. + * + * memtype_lock protects the rbtree. + */ + +static inline u64 interval_start(struct memtype *entry) +{ + return entry->start; +} + +static inline u64 interval_end(struct memtype *entry) +{ + return entry->end - 1; +} + +INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end, + interval_start, interval_end, + static, interval) + +static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED; + +enum { + MEMTYPE_EXACT_MATCH = 0, + MEMTYPE_END_MATCH = 1 +}; + +static struct memtype *memtype_match(u64 start, u64 end, int match_type) +{ + struct memtype *entry_match; + + entry_match = interval_iter_first(&memtype_rbroot, start, end-1); + + while (entry_match != NULL && entry_match->start < end) { + if ((match_type == MEMTYPE_EXACT_MATCH) && + (entry_match->start == start) && (entry_match->end == end)) + return entry_match; + + if ((match_type == MEMTYPE_END_MATCH) && + (entry_match->start < start) && (entry_match->end == end)) + return entry_match; + + entry_match = interval_iter_next(entry_match, start, end-1); + } + + return NULL; /* Returns NULL if there is no match */ +} + +static int memtype_check_conflict(u64 start, u64 end, + enum page_cache_mode reqtype, + enum page_cache_mode *newtype) +{ + struct memtype *entry_match; + enum page_cache_mode found_type = reqtype; + + entry_match = interval_iter_first(&memtype_rbroot, start, end-1); + if (entry_match == NULL) + goto success; + + if (entry_match->type != found_type && newtype == NULL) + goto failure; + + dprintk("Overlap at 0x%Lx-0x%Lx\n", entry_match->start, entry_match->end); + found_type = entry_match->type; + + entry_match = interval_iter_next(entry_match, start, end-1); + while (entry_match) { + if (entry_match->type != found_type) + goto failure; + + entry_match = interval_iter_next(entry_match, start, end-1); + } +success: + if (newtype) + *newtype = found_type; + + return 0; + +failure: + pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n", + current->comm, current->pid, start, end, + cattr_name(found_type), cattr_name(entry_match->type)); + + return -EBUSY; +} + +int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_type) +{ + int err = 0; + + err = memtype_check_conflict(entry_new->start, entry_new->end, entry_new->type, ret_type); + if (err) + return err; + + if (ret_type) + entry_new->type = *ret_type; + + interval_insert(entry_new, &memtype_rbroot); + return 0; +} + +struct memtype *memtype_erase(u64 start, u64 end) +{ + struct memtype *entry_old; + + /* + * Since the memtype_rbroot tree allows overlapping ranges, + * memtype_erase() checks with EXACT_MATCH first, i.e. free + * a whole node for the munmap case. If no such entry is found, + * it then checks with END_MATCH, i.e. shrink the size of a node + * from the end for the mremap case. + */ + entry_old = memtype_match(start, end, MEMTYPE_EXACT_MATCH); + if (!entry_old) { + entry_old = memtype_match(start, end, MEMTYPE_END_MATCH); + if (!entry_old) + return ERR_PTR(-EINVAL); + } + + if (entry_old->start == start) { + /* munmap: erase this node */ + interval_remove(entry_old, &memtype_rbroot); + } else { + /* mremap: update the end value of this node */ + interval_remove(entry_old, &memtype_rbroot); + entry_old->end = start; + interval_insert(entry_old, &memtype_rbroot); + + return NULL; + } + + return entry_old; +} + +struct memtype *memtype_lookup(u64 addr) +{ + return interval_iter_first(&memtype_rbroot, addr, addr + PAGE_SIZE-1); +} + +/* + * Debugging helper, copy the Nth entry of the tree into a + * a copy for printout. This allows us to print out the tree + * via debugfs, without holding the memtype_lock too long: + */ +#ifdef CONFIG_DEBUG_FS +int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos) +{ + struct memtype *entry_match; + int i = 1; + + entry_match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX); + + while (entry_match && pos != i) { + entry_match = interval_iter_next(entry_match, 0, ULONG_MAX); + i++; + } + + if (entry_match) { /* pos == i */ + *entry_out = *entry_match; + return 0; + } else { + return 1; + } +} +#endif diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pat/set_memory.c index 1b99ad05b117..20823392f4f2 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pat/set_memory.c @@ -24,10 +24,10 @@ #include <linux/uaccess.h> #include <asm/pgalloc.h> #include <asm/proto.h> -#include <asm/pat.h> +#include <asm/memtype.h> #include <asm/set_memory.h> -#include "mm_internal.h" +#include "../mm_internal.h" /* * The current flushing context - we pass it instead of 5 arguments: @@ -331,7 +331,7 @@ static void cpa_flush_all(unsigned long cache) on_each_cpu(__cpa_flush_all, (void *) cache, 1); } -void __cpa_flush_tlb(void *data) +static void __cpa_flush_tlb(void *data) { struct cpa_data *cpa = data; unsigned int i; @@ -1801,7 +1801,7 @@ int set_memory_uc(unsigned long addr, int numpages) /* * for now UC MINUS. see comments in ioremap() */ - ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, + ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, _PAGE_CACHE_MODE_UC_MINUS, NULL); if (ret) goto out_err; @@ -1813,7 +1813,7 @@ int set_memory_uc(unsigned long addr, int numpages) return 0; out_free: - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); + memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); out_err: return ret; } @@ -1839,14 +1839,14 @@ int set_memory_wc(unsigned long addr, int numpages) { int ret; - ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, + ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, _PAGE_CACHE_MODE_WC, NULL); if (ret) return ret; ret = _set_memory_wc(addr, numpages); if (ret) - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); + memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); return ret; } @@ -1873,7 +1873,7 @@ int set_memory_wb(unsigned long addr, int numpages) if (ret) return ret; - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); + memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); return 0; } EXPORT_SYMBOL(set_memory_wb); @@ -2014,7 +2014,7 @@ static int _set_pages_array(struct page **pages, int numpages, continue; start = page_to_pfn(pages[i]) << PAGE_SHIFT; end = start + PAGE_SIZE; - if (reserve_memtype(start, end, new_type, NULL)) + if (memtype_reserve(start, end, new_type, NULL)) goto err_out; } @@ -2040,7 +2040,7 @@ err_out: continue; start = page_to_pfn(pages[i]) << PAGE_SHIFT; end = start + PAGE_SIZE; - free_memtype(start, end); + memtype_free(start, end); } |