/* * 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 genericmm * @{ */ /** @file */ #ifndef KERN_AS_H_ #define KERN_AS_H_ #include #include #include #include #include #include #include #include #include #include #include #include /** * 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_t refcount; mutex_t lock; /** B+tree of address space areas. */ btree_t as_area_btree; /** 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; /** * 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; /** * B+tree containing complete map of anonymous pages of the shared area. */ btree_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 { /** elf_backend members */ struct { elf_header_t *elf; elf_segment_header_t *segment; }; /** phys_backend members */ struct { uintptr_t base; size_t frames; bool anonymous; }; } 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; /** Memory flags. */ unsigned int flags; /** Address space area attributes. */ unsigned int attributes; /** Number of pages in the area. */ size_t pages; /** Number of resident pages in the area. */ size_t resident; /** Base address of this area. */ uintptr_t base; /** Map of used space. */ btree_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_destroy(as_t *); 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 int as_area_destroy(as_t *, uintptr_t); extern int as_area_resize(as_t *, uintptr_t, size_t, unsigned int); extern int as_area_share(as_t *, uintptr_t, size_t, as_t *, unsigned int, uintptr_t *, uintptr_t); extern int as_area_change_flags(as_t *, unsigned int, uintptr_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 bool used_space_insert(as_area_t *, uintptr_t, size_t); extern bool used_space_remove(as_area_t *, uintptr_t, size_t); /* Interface to be implemented by architectures. */ #ifndef as_constructor_arch extern int 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 int 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; /* Address space area related syscalls. */ extern sysarg_t sys_as_area_create(uintptr_t, size_t, unsigned int, uintptr_t); extern sysarg_t sys_as_area_resize(uintptr_t, size_t, unsigned int); extern sysarg_t sys_as_area_change_flags(uintptr_t, unsigned int); extern sysarg_t sys_as_area_destroy(uintptr_t); /* Introspection functions. */ extern void as_get_area_info(as_t *, as_area_info_t **, size_t *); extern void as_print(as_t *); #endif /** @} */