| /* |
| * Copyright (c) 2016-2020, Intel Corporation |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * * Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * * Neither the name of Intel Corporation nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef PT_IMAGE_SECTION_CACHE_H |
| #define PT_IMAGE_SECTION_CACHE_H |
| |
| #include <stdint.h> |
| |
| #if defined(FEATURE_THREADS) |
| # include <threads.h> |
| #endif /* defined(FEATURE_THREADS) */ |
| |
| struct pt_section; |
| |
| |
| /* An image section cache entry. */ |
| struct pt_iscache_entry { |
| /* The section object. |
| * |
| * We hold a reference to the section - put it when the section is |
| * removed from the cache. |
| */ |
| struct pt_section *section; |
| |
| /* The base address at which @section has been loaded. */ |
| uint64_t laddr; |
| }; |
| |
| /* A cache of image sections and their load addresses. |
| * |
| * We combine the section with its load address to reduce the amount of |
| * information we need to store in order to read from a cached section by |
| * virtual address. |
| * |
| * Internally, the section object will be shared if it is loaded at different |
| * addresses in the cache. |
| * |
| * The cache does not consider the address-space the section is mapped into. |
| * This is not relevant for reading from the section. |
| */ |
| struct pt_image_section_cache { |
| /* The optional name of the cache; NULL if not named. */ |
| char *name; |
| |
| /* An array of @nentries cached sections. */ |
| struct pt_iscache_entry *entries; |
| |
| #if defined(FEATURE_THREADS) |
| /* A lock protecting this image section cache. */ |
| mtx_t lock; |
| #endif /* defined(FEATURE_THREADS) */ |
| |
| /* The capacity of the @entries array. |
| * |
| * Cached sections are identified by a positive integer, the image |
| * section identifier (isid), which is derived from their index into the |
| * @entries array. |
| * |
| * We can't expand the section cache capacity beyond INT_MAX. |
| */ |
| uint16_t capacity; |
| |
| /* The current size of the cache in number of entries. |
| * |
| * This is smaller than @capacity if there is still room in the @entries |
| * array; equal to @capacity if the @entries array is full and needs to |
| * be reallocated. |
| */ |
| uint16_t size; |
| }; |
| |
| |
| /* Initialize an image section cache. */ |
| extern int pt_iscache_init(struct pt_image_section_cache *iscache, |
| const char *name); |
| |
| /* Finalize an image section cache. */ |
| extern void pt_iscache_fini(struct pt_image_section_cache *iscache); |
| |
| /* Add a section to the cache. |
| * |
| * Adds @section at @laddr to @iscache and returns its isid. If a similar |
| * section is already cached, returns that section's isid, instead. |
| * |
| * We take a full section rather than its filename and range in that file to |
| * avoid the dependency to pt_section.h. Callers are expected to query the |
| * cache before creating the section, so we should only see unnecessary section |
| * creation/destruction on insertion races. |
| * |
| * Returns zero on success, a negative error code otherwise. |
| * Returns -pte_internal if @iscache or @section is NULL. |
| * Returns -pte_internal if @section's filename is NULL. |
| */ |
| extern int pt_iscache_add(struct pt_image_section_cache *iscache, |
| struct pt_section *section, uint64_t laddr); |
| |
| /* Find a section in the cache. |
| * |
| * Returns a positive isid if a section matching @filename, @offset, @size |
| * loaded at @laddr is found in @iscache. |
| * Returns zero if no such section is found. |
| * Returns a negative error code otherwise. |
| * Returns -pte_internal if @iscache or @filename is NULL. |
| */ |
| extern int pt_iscache_find(struct pt_image_section_cache *iscache, |
| const char *filename, uint64_t offset, |
| uint64_t size, uint64_t laddr); |
| |
| /* Lookup the section identified by its isid. |
| * |
| * Provides a reference to the section in @section and its load address in |
| * @laddr on success. The caller is expected to put the returned section after |
| * use. |
| * |
| * Returns zero on success, a negative error code otherwise. |
| * Returns -pte_internal if @iscache, @section, or @laddr is NULL. |
| * Returns -pte_bad_image if @iscache does not contain @isid. |
| */ |
| extern int pt_iscache_lookup(struct pt_image_section_cache *iscache, |
| struct pt_section **section, uint64_t *laddr, |
| int isid); |
| |
| /* Clear an image section cache. */ |
| extern int pt_iscache_clear(struct pt_image_section_cache *iscache); |
| |
| #endif /* PT_IMAGE_SECTION_CACHE_H */ |