/* * Copyright (c) 2010 Jakub Jermar * All rights reserved. * * 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. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ /** @addtogroup kernel_generic_mm * @{ */ /** @file */ #ifndef KERN_AS_H_ #define KERN_AS_H_ #include #include #include #include #include #include #include #include #include #include #include #include #include #define AS CURRENT->as /** * Defined to be true if user address space and kernel address space shadow each * other. * */ #define KERNEL_ADDRESS_SPACE_SHADOWED KERNEL_ADDRESS_SPACE_SHADOWED_ARCH #define KERNEL_ADDRESS_SPACE_START KERNEL_ADDRESS_SPACE_START_ARCH #define KERNEL_ADDRESS_SPACE_END KERNEL_ADDRESS_SPACE_END_ARCH #define USER_ADDRESS_SPACE_START USER_ADDRESS_SPACE_START_ARCH #define USER_ADDRESS_SPACE_END USER_ADDRESS_SPACE_END_ARCH /** Kernel address space. */ #define FLAG_AS_KERNEL (1 << 0) /* Address space area attributes. */ #define AS_AREA_ATTR_NONE 0 #define AS_AREA_ATTR_PARTIAL 1 /**< Not fully initialized area. */ /** The page fault was resolved by as_page_fault(). */ #define AS_PF_OK 0 /** The page fault was caused by memcpy_from_uspace() or memcpy_to_uspace(). */ #define AS_PF_DEFER 1 /** The page fault was not resolved by as_page_fault(). */ #define AS_PF_FAULT 2 /** The page fault was not resolved by as_page_fault(). Non-verbose version. */ #define AS_PF_SILENT 3 /** Address space structure. * * as_t contains the list of as_areas of userspace accessible * pages for one or more tasks. Ranges of kernel memory pages are not * supposed to figure in the list as they are shared by all tasks and * set up during system initialization. * */ typedef struct as { /** Protected by asidlock. */ link_t inactive_as_with_asid_link; /** * Number of processors on which this * address space is active. Protected by * asidlock. */ size_t cpu_refcount; /** Address space identifier. * * Constant on architectures that do not * support ASIDs. Protected by asidlock. * */ asid_t asid; /** Number of references (i.e. tasks that reference this as). */ atomic_refcount_t refcount; mutex_t lock; /** Address space areas in this address space by base address. * * Members are of type as_area_t. */ odict_t as_areas; /** Non-generic content. */ as_genarch_t genarch; /** Architecture specific content. */ as_arch_t arch; } as_t; typedef struct { pte_t *(*page_table_create)(unsigned int); void (*page_table_destroy)(pte_t *); void (*page_table_lock)(as_t *, bool); void (*page_table_unlock)(as_t *, bool); bool (*page_table_locked)(as_t *); } as_operations_t; /** Single anonymous page mapping. */ typedef struct { /** Containing pagemap structure */ struct as_pagemap *pagemap; /** Link to @c shinfo->pagemap ordered dictionary */ odlink_t lpagemap; /** Virtual address */ uintptr_t vaddr; /** Physical frame address */ uintptr_t frame; } as_page_mapping_t; /** Map of anonymous pages in a shared area. */ typedef struct as_pagemap { /** * Dictionary ordered by virtual address. Members are of type * as_page_mapping_t */ odict_t map; } as_pagemap_t; /** Used space interval */ typedef struct { /** Containing used_space structure */ struct used_space *used_space; /** Link to @c used_space->ivals */ odlink_t lused_space; /** First page address */ uintptr_t page; /** Count of pages */ size_t count; } used_space_ival_t; /** Map of used space in an address space area */ typedef struct used_space { /** * Dictionary of intervals by start address. * Members are of type @c used_space_ival_t. */ odict_t ivals; /** Total number of used pages. */ size_t pages; } used_space_t; /** * This structure contains information associated with the shared address space * area. * */ typedef struct { /** This lock must be acquired only when the as_area lock is held. */ mutex_t lock; /** This structure can be deallocated if refcount drops to 0. */ size_t refcount; /** True if the area has been ever shared. */ bool shared; /** Complete map of anonymous pages of the shared area. */ as_pagemap_t pagemap; /** Address space area backend. */ struct mem_backend *backend; /** Address space area shared data. */ void *backend_shared_data; } share_info_t; /** Page fault access type. */ typedef enum { PF_ACCESS_READ, PF_ACCESS_WRITE, PF_ACCESS_EXEC, PF_ACCESS_UNKNOWN } pf_access_t; struct mem_backend; /** Backend data stored in address space area. */ typedef union mem_backend_data { /* anon_backend members */ struct { }; /** elf_backend members */ struct { uintptr_t elf_base; elf_header_t *elf; elf_segment_header_t *segment; }; /** phys_backend members */ struct { uintptr_t base; size_t frames; bool anonymous; }; /** user_backend members */ struct { as_area_pager_info_t pager_info; }; } mem_backend_data_t; /** Address space area structure. * * Each as_area_t structure describes one contiguous area of virtual memory. * */ typedef struct { mutex_t lock; /** Containing address space. */ as_t *as; /** Link to @c as->as_areas */ odlink_t las_areas; /** Memory flags. */ unsigned int flags; /** Address space area attributes. */ unsigned int attributes; /** Number of pages in the area. */ size_t pages; /** Base address of this area. */ uintptr_t base; /** Map of used space. */ used_space_t used_space; /** * If the address space area is shared. this is * a reference to the share info structure. */ share_info_t *sh_info; /** Memory backend backing this address space area. */ struct mem_backend *backend; /** Data to be used by the backend. */ mem_backend_data_t backend_data; } as_area_t; /** Address space area backend structure. */ typedef struct mem_backend { bool (*create)(as_area_t *); bool (*resize)(as_area_t *, size_t); void (*share)(as_area_t *); void (*destroy)(as_area_t *); bool (*is_resizable)(as_area_t *); bool (*is_shareable)(as_area_t *); int (*page_fault)(as_area_t *, uintptr_t, pf_access_t); void (*frame_free)(as_area_t *, uintptr_t, uintptr_t); bool (*create_shared_data)(as_area_t *); void (*destroy_shared_data)(void *); } mem_backend_t; extern as_t *AS_KERNEL; extern as_operations_t *as_operations; extern list_t inactive_as_with_asid_list; extern void as_init(void); extern as_t *as_create(unsigned int); extern void as_hold(as_t *); extern void as_release(as_t *); extern void as_switch(as_t *, as_t *); extern int as_page_fault(uintptr_t, pf_access_t, istate_t *); extern as_area_t *as_area_create(as_t *, unsigned int, size_t, unsigned int, mem_backend_t *, mem_backend_data_t *, uintptr_t *, uintptr_t); extern errno_t as_area_destroy(as_t *, uintptr_t); extern errno_t as_area_resize(as_t *, uintptr_t, size_t, unsigned int); extern errno_t as_area_share(as_t *, uintptr_t, size_t, as_t *, unsigned int, uintptr_t *, uintptr_t); extern errno_t as_area_change_flags(as_t *, unsigned int, uintptr_t); extern as_area_t *as_area_first(as_t *); extern as_area_t *as_area_next(as_area_t *); extern void as_pagemap_initialize(as_pagemap_t *); extern void as_pagemap_finalize(as_pagemap_t *); extern as_page_mapping_t *as_pagemap_first(as_pagemap_t *); extern as_page_mapping_t *as_pagemap_next(as_page_mapping_t *); extern errno_t as_pagemap_find(as_pagemap_t *, uintptr_t, uintptr_t *); extern void as_pagemap_insert(as_pagemap_t *, uintptr_t, uintptr_t); extern void as_pagemap_remove(as_page_mapping_t *); extern unsigned int as_area_get_flags(as_area_t *); extern bool as_area_check_access(as_area_t *, pf_access_t); extern size_t as_area_get_size(uintptr_t); extern used_space_ival_t *used_space_first(used_space_t *); extern used_space_ival_t *used_space_next(used_space_ival_t *); extern used_space_ival_t *used_space_find_gteq(used_space_t *, uintptr_t); extern bool used_space_insert(used_space_t *, uintptr_t, size_t); /* Interface to be implemented by architectures. */ #ifndef as_constructor_arch extern errno_t as_constructor_arch(as_t *, unsigned int); #endif /* !def as_constructor_arch */ #ifndef as_destructor_arch extern int as_destructor_arch(as_t *); #endif /* !def as_destructor_arch */ #ifndef as_create_arch extern errno_t as_create_arch(as_t *, unsigned int); #endif /* !def as_create_arch */ #ifndef as_install_arch extern void as_install_arch(as_t *); #endif /* !def as_install_arch */ #ifndef as_deinstall_arch extern void as_deinstall_arch(as_t *); #endif /* !def as_deinstall_arch */ /* Backend declarations and functions. */ extern mem_backend_t anon_backend; extern mem_backend_t elf_backend; extern mem_backend_t phys_backend; extern mem_backend_t user_backend; /* Address space area related syscalls. */ extern sysarg_t sys_as_area_create(uintptr_t, size_t, unsigned int, uintptr_t, as_area_pager_info_t *); extern sys_errno_t sys_as_area_resize(uintptr_t, size_t, unsigned int); extern sys_errno_t sys_as_area_change_flags(uintptr_t, unsigned int); extern sys_errno_t sys_as_area_get_info(uintptr_t, as_area_info_t *); extern sys_errno_t sys_as_area_destroy(uintptr_t); /* Introspection functions. */ extern as_area_info_t *as_get_area_info(as_t *, size_t *); extern void as_print(as_t *); #endif /** @} */