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Diffstat (limited to 'include/apos/mem_regions.h')
| -rw-r--r-- | include/apos/mem_regions.h | 303 |
1 files changed, 0 insertions, 303 deletions
diff --git a/include/apos/mem_regions.h b/include/apos/mem_regions.h deleted file mode 100644 index 6fdb5b4..0000000 --- a/include/apos/mem_regions.h +++ /dev/null @@ -1,303 +0,0 @@ -/* SPDX-License-Identifier: GPL-3.0-or-later */ -/* Copyright 2021 - 2022, Kim Kuparinen < kimi.h.kuparinen@gmail.com > */ - -#ifndef APOS_MEM_REGIONS_H -#define APOS_MEM_REGIONS_H - -/** - * @file mem_regions.h - * Memory region subsytem. Mainly used by the virtual memory subsytems, i.e. device and - * user memory. - */ - -#include <apos/mem.h> -#include <arch/vmem.h> -#include <apos/types.h> -#include <apos/sp_tree.h> - -/** - * Get \ref mem_region container of \c ptr. - * - * @param ptr Pointer to \c sp_n member in \ref mem_region. - * @return Parent \ref mem_region. - */ -#define mem_container(ptr) container_of(ptr, struct mem_region, sp_n) - -/** - * Check if memory region is used. - * - * @param r Memory region to check. - * @return \c 0 if not used, non-zero otherwise. - */ -#define is_region_used(r) is_set(r->flags, MR_USED) - -/** - * Check if region should be kept during clear. - * - * @param r Memory region to check. - * @return \c 0 if not kept, non-zero otherwise. - */ -#define is_region_kept(r) is_set(r->flags, MR_KEEP) - -/** Root of memory region. */ -struct mem_region_root { - /** Sp-tree of free regions. */ - struct sp_root free_regions; - - /** Sp-tree of used region. */ - struct sp_root used_regions; -}; - -/** - * Memory region. - * Regions can have two states, used or free. There are two sp-trees, which keep - * track of free and used regions, respectively. All regions are chained - * together with a doubly linked list, so that the next region's start address - * should be the current region's end address. - */ -struct mem_region { - /** Sp-tree node slot. */ - struct sp_node sp_n; - - /** Next memory region by start address. */ - struct mem_region *next; - - /** Previous memory region by end address. */ - struct mem_region *prev; - - /** Memory region flags, both access as well as metadata. \see MR_USED, - * MR_SHARED, MR_OWNED, MR_COW, MR_KEEP. */ - vmflags_t flags; - - /** End address of memory region. */ - vm_t end; - - /** Start address of memory region. */ - vm_t start; - - /** In shared regions, mark the other pid that shared the region. */ - id_t pid; - - /** In shared regions, this is the address associated with region in the - * other process. */ - vm_t alt_va; -}; - -/** - * Initialize memory region subsystem instance. - * - * @param r Memory region root to initialize. - * @param start Start of memory arena. - * @param arena_size Size of memory arena. - * @return \ref OK on success. - * \todo Document error codes when I actually implement them properly. - */ -stat_t init_region(struct mem_region_root *r, vm_t start, size_t arena_size); - -/** - * Destroy memory region subsystem instance. - * - * @param r Memory region root to destroy. - * @return \ref OK on success. - */ -stat_t destroy_region(struct mem_region_root *r); - -/** - * Allocate memory region. - * Will allocate region of at least \c size bytes, with best possible location. - * - * @param r Memory region root. - * @param size Size of region to allocate. - * @param actual_size Size of region that was allocated. - * @param flags Memory flags. - * @return Address of allocated region on success, otherwise \c NULL. - */ -vm_t alloc_region(struct mem_region_root *r, size_t size, size_t *actual_size, - vmflags_t flags); - -/** - * Allocate memory region and associate it with some other process. - * Will allocate region of at least \c size bytes, with best possible location. - * - * @param r Memory region root. - * @param size Size of region to allocate. - * @param actual_size Size of region that was allocated. - * @param flags Memory flags. - * @param pid Process to associate with region. - * @return Address of allocated region on success, otherwise \c NULL. - */ -vm_t alloc_shared_region(struct mem_region_root *r, size_t size, - size_t *actual_size, - vmflags_t flags, id_t pid); - -/** - * Allocate fixed memory region. - * Will allocate region that is at least \c size bytes, and includes \c start. - * \note The address returned might not be the address requested, and the caller - * must keep track of which address it was given, so it can cleanly give it to - * \ref free_region() when finished with the allocation. - * - * @param r Memory region root. - * @param start Address that must be within region to allocate. - * @param size Size of region to allocate. - * @param actual_size Size of region that was allocated. - * @param flags Memory flags. - * @return Address of allocated region on success, otherwise \c NULL. - */ -vm_t alloc_fixed_region(struct mem_region_root *r, vm_t start, size_t size, - size_t *actual_size, vmflags_t flags); - -/** - * Free memory region. - * - * @param r Memory region root. - * @param start Address of region to free. - * @return \ref OK on success, \ref ERR_ALIGN if \c start is misaligned and \ref - * ERR_NF if the memory region is not found. - */ -stat_t free_region(struct mem_region_root *r, vm_t start); - -/** - * Free memory region through a direct pointer to the memory region. - * Mainly useful if you look up a region beforehand, do something with it and - * then free it. Skips looking up the start address. - * - * @param r Memory region root. - * @param m Memory region to free. - * @return \ref OK. - * \todo Improve error checking. - */ -stat_t free_known_region(struct mem_region_root *r, struct mem_region *m); - -/** - * Find the memory region with lowest starting address. - * This region will also be the first node in the linked list. - * Useful when you need to iterate over all regions. - * - * @param r Memory region root. - * @return First memory region when succesful, otherwise \c NULL. - */ -struct mem_region *find_first_region(struct mem_region_root *r); - -/** - * Find used memory region at address \c start. - * - * @param r Memory region root. - * @param start Address at which a used region should exist. - * @return Pointer to requested memory region when succesful, \c NULL otherwise. - */ -struct mem_region *find_used_region(struct mem_region_root *r, vm_t start); - -/** - * Find used memory region closest to \c start. - * Useful when you don't necessarily need the exact region, just something close - * by. - * - * @param r Memory region root. - * @param start Address region should be closest to. - * @return Pointer to memory region closest to \c start when succesful, \c NULL - * otherwise. - */ -struct mem_region *find_closest_used_region(struct mem_region_root *r, - vm_t start); - -/** - * Find best region that fulfills requested parameters. - * - * @param r Memory region root. - * @param size Size of free region. - * @param align Recommended offset into this region from where the allocation - * should be carved. - * @return Pointer to suitable \c memory_region when succesful, \c NULL - * otherwise. - */ -struct mem_region *find_free_region(struct mem_region_root *r, size_t size, - size_t *align); - -/** - * Helper functions for converting between memory regions and page - * mappings. Called by \ref map_fill_region(). - * \see map_fill_region() for further explanation. - * - * @param vmem Virtual memory space in which the operation is to be done. - * @param offset Offset from where to start looking for next physical page. \see - * alloc_page(). - * @param vaddr Current virtual address. - * @param flags Virtual memory allocation flags. - * @param order Order of physical page. - * @param data Custom data. - * @return \ref OK if succesful, \c INFO_TRGN if page order should be decreased, - * anything else means error. - */ -typedef stat_t region_callback_t(struct vmem *vmem, pm_t *offset, vm_t vaddr, - vmflags_t flags, enum mm_order order, - void *data); - -/** - * Query flags of region that contains \c va. - * - * @param r Memory region root. - * @param va Address that is within memory region. - * @param flags Memory region flags. - * @return \ref OK when succesful. - * \todo Implement. - */ -stat_t stat_region(struct mem_region_root *r, vm_t va, vmflags_t *flags); - -/** - * Modify flags of region that contains \c va. - * - * @param r Memory region root. - * @param va Address that is within memory region. - * @param flags New flags of region. - * @return \ref OK when succesful. - * \todo Implement. - */ -stat_t mod_region(struct mem_region_root *r, vm_t va, vmflags_t flags); - -/** - * Set alternate virtual address associated with shared memory region in other process. - * - * @param r Memory region root. - * @param va Virtual address in \p r. - * @param alt_va Virtual address in other process. - */ -void set_alt_region_addr(struct mem_region_root *r, vm_t va, vm_t alt_va); - -/** - * Conversion function between abstract memory region and actual page mappings. - * Assumes that pages of some order are mappable at multiples of their size, and - * tries to fit as many and as high order pages as it can into the region. - * Heavily utilizes \c mem_handler, to which it gives a suggestion for how to - * map a page. If this suggestion is accepted and succesfully executed, \c mem_handler - * returns \ref OK. If the suggestion is not possible, for example no higher - * order pages are available, \c mem_handler returns \ref INFO_TRGN to tell \c - * map_fill_region() to give it some other suggestion. Any error value stops the - * conversion. - * - * This 'algorithm' also works quite nicely for freeing a region, but in - * reverse, i.e. it is given a suggestion and checks if that suggestion was - * executed when the region was mapped. If the suggestion was executed, then the - * same suggestion is freed, else \ref INFO_TRGN is returned and a new - * suggestion is requested until all pages have been freed. - * - * There are some more technicalities, for example currently \c - * map_fill_region() gives up trying to map higher order pages as soon as its - * first suggestion is rejected, which gives us quick conversion times but - * probably less than ideal mappings. - * - * @param vmem Virtual memory inside which to map the region. - * @param mem_handler Worker handler callback. - * @param offset Offset at which the physical memory availability map should - * start searching. - * @param start Start address of memory region. - * @param bytes Size of memory region. - * @param flags Memory flags. - * @param data User-specified data. - * @return \c start when succesful, \c 0 otherwise. - */ -vm_t map_fill_region(struct vmem *vmem, region_callback_t *mem_handler, - pm_t offset, vm_t start, size_t bytes, vmflags_t flags, - void *data); - -#endif /* APOS_MEM_REGIONS_H */ |