[PATCH 4/5] mm/vmalloc: remove unmap_kernel_range
From: Nicholas Piggin <npiggin@gmail.com>
Date: 2021-01-26 23:17:34
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Subsystem:
arm64 port (aarch64 architecture), documentation, linux for powerpc (32-bit and 64-bit), memory management, memory management - core, pci subsystem, per-cpu memory allocator, the rest, vmalloc · Maintainers:
Catalin Marinas, Will Deacon, Jonathan Corbet, Madhavan Srinivasan, Michael Ellerman, Andrew Morton, David Hildenbrand, Bjorn Helgaas, Dennis Zhou, Tejun Heo, Christoph Lameter, Linus Torvalds, Uladzislau Rezki
This is a shim around vunmap_range, get rid of it. Move the main API comment from the _noflush variant to the normal variant, and make _noflush internal to mm/. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- Documentation/core-api/cachetlb.rst | 2 +- arch/arm64/mm/init.c | 2 +- arch/powerpc/kernel/isa-bridge.c | 4 +- arch/powerpc/kernel/pci_64.c | 2 +- arch/powerpc/mm/ioremap.c | 2 +- drivers/pci/pci.c | 2 +- include/linux/vmalloc.h | 8 +--- mm/internal.h | 1 + mm/percpu-vm.c | 2 +- mm/vmalloc.c | 59 ++++++++++++++--------------- 10 files changed, 38 insertions(+), 46 deletions(-)
diff --git a/Documentation/core-api/cachetlb.rst b/Documentation/core-api/cachetlb.rst
index 756f7bcf8191..fe4290e26729 100644
--- a/Documentation/core-api/cachetlb.rst
+++ b/Documentation/core-api/cachetlb.rst@@ -215,7 +215,7 @@ Here are the routines, one by one: The first of these two routines is invoked after vmap_range() has installed the page table entries. The second is invoked - before unmap_kernel_range() deletes the page table entries. + before vunmap_range() deletes the page table entries. There exists another whole class of cpu cache issues which currently require a whole different set of interfaces to handle properly.
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 709d98fea90c..7fe0a5074205 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c@@ -498,7 +498,7 @@ void free_initmem(void) * prevents the region from being reused for kernel modules, which * is not supported by kallsyms. */ - unmap_kernel_range((u64)__init_begin, (u64)(__init_end - __init_begin)); + vunmap_range((u64)__init_begin, (u64)__init_end); } void dump_mem_limit(void)
diff --git a/arch/powerpc/kernel/isa-bridge.c b/arch/powerpc/kernel/isa-bridge.c
index 2257d24e6a26..39c625737c09 100644
--- a/arch/powerpc/kernel/isa-bridge.c
+++ b/arch/powerpc/kernel/isa-bridge.c@@ -48,7 +48,7 @@ static void remap_isa_base(phys_addr_t pa, unsigned long size) if (slab_is_available()) { if (ioremap_page_range(ISA_IO_BASE, ISA_IO_BASE + size, pa, pgprot_noncached(PAGE_KERNEL))) - unmap_kernel_range(ISA_IO_BASE, size); + vunmap_range(ISA_IO_BASE, ISA_IO_BASE + size); } else { early_ioremap_range(ISA_IO_BASE, pa, size, pgprot_noncached(PAGE_KERNEL));
@@ -311,7 +311,7 @@ static void isa_bridge_remove(void) isa_bridge_pcidev = NULL; /* Unmap the ISA area */ - unmap_kernel_range(ISA_IO_BASE, 0x10000); + vunmap_range(ISA_IO_BASE, ISA_IO_BASE + 0x10000); } /**
diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
index 9312e6eda7ff..3fb7e572abed 100644
--- a/arch/powerpc/kernel/pci_64.c
+++ b/arch/powerpc/kernel/pci_64.c@@ -140,7 +140,7 @@ void __iomem *ioremap_phb(phys_addr_t paddr, unsigned long size) addr = (unsigned long)area->addr; if (ioremap_page_range(addr, addr + size, paddr, pgprot_noncached(PAGE_KERNEL))) { - unmap_kernel_range(addr, size); + vunmap_range(addr, addr + size); return NULL; }
diff --git a/arch/powerpc/mm/ioremap.c b/arch/powerpc/mm/ioremap.c
index b1a0aebe8c48..57342154d2b0 100644
--- a/arch/powerpc/mm/ioremap.c
+++ b/arch/powerpc/mm/ioremap.c@@ -93,7 +93,7 @@ void __iomem *do_ioremap(phys_addr_t pa, phys_addr_t offset, unsigned long size, if (!ret) return (void __iomem *)area->addr + offset; - unmap_kernel_range(va, size); + vunmap_range(va, va + size); free_vm_area(area); return NULL;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index b9fecc25d213..d1e5ee09b381 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c@@ -4107,7 +4107,7 @@ void pci_unmap_iospace(struct resource *res) #if defined(PCI_IOBASE) && defined(CONFIG_MMU) unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start; - unmap_kernel_range(vaddr, resource_size(res)); + vunmap_range(vaddr, vaddr + resource_size(res)); #endif } EXPORT_SYMBOL(pci_unmap_iospace);
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 913c9d4f5e03..b569a13c9960 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h@@ -217,8 +217,7 @@ static inline bool is_vm_area_hugepages(const void *addr) int vmap_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, unsigned int max_page_shift); -extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size); -extern void unmap_kernel_range(unsigned long addr, unsigned long size); +void vunmap_range(unsigned long addr, unsigned long end); static inline void set_vm_flush_reset_perms(void *addr) { struct vm_struct *vm = find_vm_area(addr);
@@ -228,11 +227,6 @@ static inline void set_vm_flush_reset_perms(void *addr) } #else -static inline void -unmap_kernel_range_noflush(unsigned long addr, unsigned long size) -{ -} -#define unmap_kernel_range unmap_kernel_range_noflush static inline void set_vm_flush_reset_perms(void *addr) { }
diff --git a/mm/internal.h b/mm/internal.h
index 3ce246945882..3d4449f79582 100644
--- a/mm/internal.h
+++ b/mm/internal.h@@ -628,5 +628,6 @@ struct migration_target_control { */ int vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift); +void vunmap_range_noflush(unsigned long start, unsigned long end); #endif /* __MM_INTERNAL_H */
diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c
index 88a53eb68a94..8d3844bc0c7c 100644
--- a/mm/percpu-vm.c
+++ b/mm/percpu-vm.c@@ -134,7 +134,7 @@ static void pcpu_pre_unmap_flush(struct pcpu_chunk *chunk, static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) { - unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT); + vunmap_range_noflush(addr, addr + (nr_pages << PAGE_SHIFT)); } /**
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 78dc3ec457ef..5ff190590fe4 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c@@ -378,22 +378,20 @@ static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, } while (p4d++, addr = next, addr != end); } -/** - * unmap_kernel_range_noflush - unmap kernel VM area - * @start: start of the VM area to unmap - * @size: size of the VM area to unmap +/* + * vunmap_range_noflush is similar to vunmap_range, but does not + * flush caches or TLBs. * - * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size specify - * should have been allocated using get_vm_area() and its friends. + * The caller is responsible for calling flush_cache_vmap() before calling + * this function, and flush_tlb_kernel_range after it has returned + * successfully (and before the addresses are expected to cause a page fault + * or be re-mapped for something else, if TLB flushes are being delayed or + * coalesced). * - * NOTE: - * This function does NOT do any cache flushing. The caller is responsible - * for calling flush_cache_vunmap() on to-be-mapped areas before calling this - * function and flush_tlb_kernel_range() after. + * This is an internal function only. Do not use outside mm/. */ -void unmap_kernel_range_noflush(unsigned long start, unsigned long size) +void vunmap_range_noflush(unsigned long start, unsigned long end) { - unsigned long end = start + size; unsigned long next; pgd_t *pgd; unsigned long addr = start;
@@ -414,6 +412,22 @@ void unmap_kernel_range_noflush(unsigned long start, unsigned long size) arch_sync_kernel_mappings(start, end); } +/** + * vunmap_range_noflush - unmap kernel virtual addresses + * @addr: start of the VM area to unmap + * @end: end of the VM area to unmap (non-inclusive) + * + * Clears any present PTEs in the virtual address range, flushes TLBs and + * caches. Any subsequent access to the address before it has been re-mapped + * is a kernel bug. + */ +void vunmap_range(unsigned long addr, unsigned long end) +{ + flush_cache_vunmap(addr, end); + vunmap_range_noflush(addr, end); + flush_tlb_kernel_range(addr, end); +} + static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, int *nr, pgtbl_mod_mask *mask)
@@ -1712,7 +1726,7 @@ static void free_vmap_area_noflush(struct vmap_area *va) static void free_unmap_vmap_area(struct vmap_area *va) { flush_cache_vunmap(va->va_start, va->va_end); - unmap_kernel_range_noflush(va->va_start, va->va_end - va->va_start); + vunmap_range_noflush(va->va_start, va->va_end); if (debug_pagealloc_enabled_static()) flush_tlb_kernel_range(va->va_start, va->va_end);
@@ -1990,7 +2004,7 @@ static void vb_free(unsigned long addr, unsigned long size) offset = (addr & (VMAP_BLOCK_SIZE - 1)) >> PAGE_SHIFT; vb = xa_load(&vmap_blocks, addr_to_vb_idx(addr)); - unmap_kernel_range_noflush(addr, size); + vunmap_range_noflush(addr, addr + size); if (debug_pagealloc_enabled_static()) flush_tlb_kernel_range(addr, addr + size);
@@ -2307,23 +2321,6 @@ void __init vmalloc_init(void) vmap_initialized = true; } -/** - * unmap_kernel_range - unmap kernel VM area and flush cache and TLB - * @addr: start of the VM area to unmap - * @size: size of the VM area to unmap - * - * Similar to unmap_kernel_range_noflush() but flushes vcache before - * the unmapping and tlb after. - */ -void unmap_kernel_range(unsigned long addr, unsigned long size) -{ - unsigned long end = addr + size; - - flush_cache_vunmap(addr, end); - unmap_kernel_range_noflush(addr, size); - flush_tlb_kernel_range(addr, end); -} - static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, struct vmap_area *va, unsigned long flags, const void *caller) {
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2.23.0