123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333 |
- /* SPDX-License-Identifier: GPL-2.0 */
- /*
- * KMSAN API for subsystems.
- *
- * Copyright (C) 2017-2022 Google LLC
- * Author: Alexander Potapenko <[email protected]>
- *
- */
- #ifndef _LINUX_KMSAN_H
- #define _LINUX_KMSAN_H
- #include <linux/dma-direction.h>
- #include <linux/gfp.h>
- #include <linux/kmsan-checks.h>
- #include <linux/types.h>
- struct page;
- struct kmem_cache;
- struct task_struct;
- struct scatterlist;
- struct urb;
- #ifdef CONFIG_KMSAN
- /**
- * kmsan_task_create() - Initialize KMSAN state for the task.
- * @task: task to initialize.
- */
- void kmsan_task_create(struct task_struct *task);
- /**
- * kmsan_task_exit() - Notify KMSAN that a task has exited.
- * @task: task about to finish.
- */
- void kmsan_task_exit(struct task_struct *task);
- /**
- * kmsan_init_shadow() - Initialize KMSAN shadow at boot time.
- *
- * Allocate and initialize KMSAN metadata for early allocations.
- */
- void __init kmsan_init_shadow(void);
- /**
- * kmsan_init_runtime() - Initialize KMSAN state and enable KMSAN.
- */
- void __init kmsan_init_runtime(void);
- /**
- * kmsan_memblock_free_pages() - handle freeing of memblock pages.
- * @page: struct page to free.
- * @order: order of @page.
- *
- * Freed pages are either returned to buddy allocator or held back to be used
- * as metadata pages.
- */
- bool __init kmsan_memblock_free_pages(struct page *page, unsigned int order);
- /**
- * kmsan_alloc_page() - Notify KMSAN about an alloc_pages() call.
- * @page: struct page pointer returned by alloc_pages().
- * @order: order of allocated struct page.
- * @flags: GFP flags used by alloc_pages()
- *
- * KMSAN marks 1<<@order pages starting at @page as uninitialized, unless
- * @flags contain __GFP_ZERO.
- */
- void kmsan_alloc_page(struct page *page, unsigned int order, gfp_t flags);
- /**
- * kmsan_free_page() - Notify KMSAN about a free_pages() call.
- * @page: struct page pointer passed to free_pages().
- * @order: order of deallocated struct page.
- *
- * KMSAN marks freed memory as uninitialized.
- */
- void kmsan_free_page(struct page *page, unsigned int order);
- /**
- * kmsan_copy_page_meta() - Copy KMSAN metadata between two pages.
- * @dst: destination page.
- * @src: source page.
- *
- * KMSAN copies the contents of metadata pages for @src into the metadata pages
- * for @dst. If @dst has no associated metadata pages, nothing happens.
- * If @src has no associated metadata pages, @dst metadata pages are unpoisoned.
- */
- void kmsan_copy_page_meta(struct page *dst, struct page *src);
- /**
- * kmsan_slab_alloc() - Notify KMSAN about a slab allocation.
- * @s: slab cache the object belongs to.
- * @object: object pointer.
- * @flags: GFP flags passed to the allocator.
- *
- * Depending on cache flags and GFP flags, KMSAN sets up the metadata of the
- * newly created object, marking it as initialized or uninitialized.
- */
- void kmsan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags);
- /**
- * kmsan_slab_free() - Notify KMSAN about a slab deallocation.
- * @s: slab cache the object belongs to.
- * @object: object pointer.
- *
- * KMSAN marks the freed object as uninitialized.
- */
- void kmsan_slab_free(struct kmem_cache *s, void *object);
- /**
- * kmsan_kmalloc_large() - Notify KMSAN about a large slab allocation.
- * @ptr: object pointer.
- * @size: object size.
- * @flags: GFP flags passed to the allocator.
- *
- * Similar to kmsan_slab_alloc(), but for large allocations.
- */
- void kmsan_kmalloc_large(const void *ptr, size_t size, gfp_t flags);
- /**
- * kmsan_kfree_large() - Notify KMSAN about a large slab deallocation.
- * @ptr: object pointer.
- *
- * Similar to kmsan_slab_free(), but for large allocations.
- */
- void kmsan_kfree_large(const void *ptr);
- /**
- * kmsan_map_kernel_range_noflush() - Notify KMSAN about a vmap.
- * @start: start of vmapped range.
- * @end: end of vmapped range.
- * @prot: page protection flags used for vmap.
- * @pages: array of pages.
- * @page_shift: page_shift passed to vmap_range_noflush().
- *
- * KMSAN maps shadow and origin pages of @pages into contiguous ranges in
- * vmalloc metadata address range. Returns 0 on success, callers must check
- * for non-zero return value.
- */
- int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
- pgprot_t prot, struct page **pages,
- unsigned int page_shift);
- /**
- * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap.
- * @start: start of vunmapped range.
- * @end: end of vunmapped range.
- *
- * KMSAN unmaps the contiguous metadata ranges created by
- * kmsan_map_kernel_range_noflush().
- */
- void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end);
- /**
- * kmsan_ioremap_page_range() - Notify KMSAN about a ioremap_page_range() call.
- * @addr: range start.
- * @end: range end.
- * @phys_addr: physical range start.
- * @prot: page protection flags used for ioremap_page_range().
- * @page_shift: page_shift argument passed to vmap_range_noflush().
- *
- * KMSAN creates new metadata pages for the physical pages mapped into the
- * virtual memory. Returns 0 on success, callers must check for non-zero return
- * value.
- */
- int kmsan_ioremap_page_range(unsigned long addr, unsigned long end,
- phys_addr_t phys_addr, pgprot_t prot,
- unsigned int page_shift);
- /**
- * kmsan_iounmap_page_range() - Notify KMSAN about a iounmap_page_range() call.
- * @start: range start.
- * @end: range end.
- *
- * KMSAN unmaps the metadata pages for the given range and, unlike for
- * vunmap_page_range(), also deallocates them.
- */
- void kmsan_iounmap_page_range(unsigned long start, unsigned long end);
- /**
- * kmsan_handle_dma() - Handle a DMA data transfer.
- * @page: first page of the buffer.
- * @offset: offset of the buffer within the first page.
- * @size: buffer size.
- * @dir: one of possible dma_data_direction values.
- *
- * Depending on @direction, KMSAN:
- * * checks the buffer, if it is copied to device;
- * * initializes the buffer, if it is copied from device;
- * * does both, if this is a DMA_BIDIRECTIONAL transfer.
- */
- void kmsan_handle_dma(struct page *page, size_t offset, size_t size,
- enum dma_data_direction dir);
- /**
- * kmsan_handle_dma_sg() - Handle a DMA transfer using scatterlist.
- * @sg: scatterlist holding DMA buffers.
- * @nents: number of scatterlist entries.
- * @dir: one of possible dma_data_direction values.
- *
- * Depending on @direction, KMSAN:
- * * checks the buffers in the scatterlist, if they are copied to device;
- * * initializes the buffers, if they are copied from device;
- * * does both, if this is a DMA_BIDIRECTIONAL transfer.
- */
- void kmsan_handle_dma_sg(struct scatterlist *sg, int nents,
- enum dma_data_direction dir);
- /**
- * kmsan_handle_urb() - Handle a USB data transfer.
- * @urb: struct urb pointer.
- * @is_out: data transfer direction (true means output to hardware).
- *
- * If @is_out is true, KMSAN checks the transfer buffer of @urb. Otherwise,
- * KMSAN initializes the transfer buffer.
- */
- void kmsan_handle_urb(const struct urb *urb, bool is_out);
- /**
- * kmsan_unpoison_entry_regs() - Handle pt_regs in low-level entry code.
- * @regs: struct pt_regs pointer received from assembly code.
- *
- * KMSAN unpoisons the contents of the passed pt_regs, preventing potential
- * false positive reports. Unlike kmsan_unpoison_memory(),
- * kmsan_unpoison_entry_regs() can be called from the regions where
- * kmsan_in_runtime() returns true, which is the case in early entry code.
- */
- void kmsan_unpoison_entry_regs(const struct pt_regs *regs);
- #else
- static inline void kmsan_init_shadow(void)
- {
- }
- static inline void kmsan_init_runtime(void)
- {
- }
- static inline bool kmsan_memblock_free_pages(struct page *page,
- unsigned int order)
- {
- return true;
- }
- static inline void kmsan_task_create(struct task_struct *task)
- {
- }
- static inline void kmsan_task_exit(struct task_struct *task)
- {
- }
- static inline int kmsan_alloc_page(struct page *page, unsigned int order,
- gfp_t flags)
- {
- return 0;
- }
- static inline void kmsan_free_page(struct page *page, unsigned int order)
- {
- }
- static inline void kmsan_copy_page_meta(struct page *dst, struct page *src)
- {
- }
- static inline void kmsan_slab_alloc(struct kmem_cache *s, void *object,
- gfp_t flags)
- {
- }
- static inline void kmsan_slab_free(struct kmem_cache *s, void *object)
- {
- }
- static inline void kmsan_kmalloc_large(const void *ptr, size_t size,
- gfp_t flags)
- {
- }
- static inline void kmsan_kfree_large(const void *ptr)
- {
- }
- static inline int kmsan_vmap_pages_range_noflush(unsigned long start,
- unsigned long end,
- pgprot_t prot,
- struct page **pages,
- unsigned int page_shift)
- {
- return 0;
- }
- static inline void kmsan_vunmap_range_noflush(unsigned long start,
- unsigned long end)
- {
- }
- static inline int kmsan_ioremap_page_range(unsigned long start,
- unsigned long end,
- phys_addr_t phys_addr, pgprot_t prot,
- unsigned int page_shift)
- {
- return 0;
- }
- static inline void kmsan_iounmap_page_range(unsigned long start,
- unsigned long end)
- {
- }
- static inline void kmsan_handle_dma(struct page *page, size_t offset,
- size_t size, enum dma_data_direction dir)
- {
- }
- static inline void kmsan_handle_dma_sg(struct scatterlist *sg, int nents,
- enum dma_data_direction dir)
- {
- }
- static inline void kmsan_handle_urb(const struct urb *urb, bool is_out)
- {
- }
- static inline void kmsan_unpoison_entry_regs(const struct pt_regs *regs)
- {
- }
- #endif
- #endif /* _LINUX_KMSAN_H */
|