/* * vmm.h - virtual memory management related operations * * Authors Ghassan Almaless (2008,2009,2010,2011, 2012) * Mohamed Lamine Karaoui (2015) * Alain Greiner (2016,2017) * * Copyright (c) UPMC Sorbonne Universites * * This file is part of ALMOS-MKH. * * ALMOS-MKH is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2.0 of the License. * * ALMOS-MKH is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with ALMOS-MKH; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _VMM_H_ #define _VMM_H_ #include #include #include #include #include #include #include #include /**** Forward declarations ****/ struct process_s; /********************************************************************************************* * This structure defines the STACK allocator used by the VMM to dynamically allocate * STACK vsegs requested or released by the user process. * This allocator handles a fixed size array of fixed size slots stores in the STACK zone. * The stack size and the number of slots are defined by the CONFIG_VMM_STACK_SIZE, and * CONFIG_THREAD * Each slot can contain one user stack vseg. The first page in the slot is not allocated * to detect stack overflow. * The slot index can be computed form the slot base address, and reversely. * All allocation / release operations are registered in the stack_bitmap, that completely * define the STACK zone state. * In this implementation, the max number of slots is 32. ********************************************************************************************/ typedef struct stack_mgr_s { spinlock_t lock; /*! lock protecting STACK allocator */ vpn_t vpn_base; /*! first page of STACK zone */ bitmap_t bitmap; /*! bit bector of allocated stacks */ } stack_mgr_t; /********************************************************************************************* * This structure defines the MMAP allocator used by the VMM to dynamically allocate * MMAP vsegs requested or released by an user process. * This allocator should be only used in the reference cluster. * - allocation policy : all allocated vsegs occupy an integer number of pages that is * power of 2, and are aligned on a page boundary. The requested number of pages is * rounded if required. The first_free_vpn variable defines completely the MMAP zone state. * It is never decremented, as the released vsegs are simply registered in a zombi_list. * The relevant zombi_list is checked first for each allocation request. * - release policy : a released MMAP vseg is registered in an array of zombi_lists. * This array is indexed by ln(number of pages), and each entry contains the root of * a local list of zombi vsegs that have the same size. The physical memory allocated * for a zombi vseg descriptor is not released, to use the "list" field. * This physical memory allocated for MMAP vseg descriptors is actually released * when the VMM is destroyed. ********************************************************************************************/ typedef struct mmap_mgr_s { spinlock_t lock; /*! lock protecting MMAP allocator */ vpn_t vpn_base; /*! first page of MMAP zone */ vpn_t vpn_size; /*! number of pages in MMAP zone */ vpn_t first_free_vpn; /*! first free page in MMAP zone */ list_entry_t zombi_list[32]; /*! array of roots of released vsegs lists */ } mmap_mgr_t; /********************************************************************************************* * This structure defines the Virtual Memory Manager for a given process in a given cluster. * This local VMM provides three main services: * 1) It registers all vsegs statically or dynamically defined in the vseg list, * and in the associated radix-tree. * 2) It allocates virtual memory space for the STACKS and MMAP vsegs, * using dedicated allocators. * 3) It contains the local copy of the generic page table descriptor. ********************************************************************************************/ typedef struct vmm_s { rwlock_t vsegs_lock; /*! lock protecting the vsegs list & radix tree */ list_entry_t vsegs_root; /*! all vsegs in same process and same cluster */ uint32_t vsegs_nr; /*! total number of local vsegs */ grdxt_t grdxt; /*! embedded generic vsegs radix tree (key is vpn) */ gpt_t gpt; /*! embedded generic page table descriptor */ stack_mgr_t stack_mgr; /*! embedded STACK vsegs allocator */ mmap_mgr_t mmap_mgr; /*! embedded MMAP vsegs allocator */ uint32_t pgfault_nr; /*! page fault counter */ uint32_t u_err_nr; /*! TODO ??? [AG] */ uint32_t m_err_nr; /*! TODO ??? [AG] */ vpn_t kent_vpn_base; /*! kentry vseg first page */ vpn_t args_vpn_base; /*! args vseg first page */ vpn_t envs_vpn_base; /*! envs zone first page */ vpn_t heap_vpn_base; /*! envs zone first page */ vpn_t code_vpn_base; /*! code zone first page */ vpn_t data_vpn_base; /*! data zone first page */ intptr_t entry_point; /*! main thread entry point */ vseg_t * heap_vseg; /*! pointer on local heap vseg descriptor */ } vmm_t; /********************************************************************************************* * This structure is used to store the arguments of the mmap() system call. ********************************************************************************************/ typedef struct mmap_attr_s { void * addr; /*! requested virtual address (unused : should be NULL) */ uint32_t length; /*! requested vseg size (bytes) */ uint32_t prot; /*! access modes */ uint32_t flags; /*! only MAP_FILE / MAP_ANON / MAP_PRIVATE / MAP_SHARED */ fdid_t fdid; /*! file descriptor index (if MAP_FILE is set) */ int32_t offset; /*! file offset (if MAP_FILE is set) */ } mmap_attr_t; /********************************************************************************************* * This function initialises the virtual memory manager attached to a process. * - It initializes the VSL (list of vsegs and associated radix tree). * - It initializes the generic page table (empty). * - It initializes the STAK and MMAP allocators. * - It registers the "kentry", "args", "envs" and "heap" vsegs in the vsegs list. * Any error in this function gives a kernel panic. ********************************************************************************************* * @ process : pointer on process descriptor ********************************************************************************************/ void vmm_init( struct process_s * process ); /********************************************************************************************* * This function copies the content of a source VMM to a destination VMM. ********************************************************************************************* * @ dst_process : pointer on destination process descriptor. * @ src_process : pointer on source process descriptor. * @ return 0 if success / return ENOMEM if failure. ********************************************************************************************/ error_t vmm_copy( struct process_s * dst_process, struct process_s * src_process ); /********************************************************************************************* * This function removes all vsegs registered in in a virtual memory manager, * and releases the memory allocated to the local generic page table. ********************************************************************************************* * @ process : pointer on process descriptor. ********************************************************************************************/ void vmm_destroy( struct process_s * process ); /********************************************************************************************* * This function scans the list of vsegs registered in the VMM of a given process descriptor * to check if a given virtual region (defined by a base and size) overlap an existing vseg. ********************************************************************************************* * @ process : pointer on process descriptor. * @ base : region virtual base address. * @ size : region size (bytes). * @ returns NULL if no conflict / return conflicting vseg pointer if conflict. ********************************************************************************************/ vseg_t * vmm_check_conflict( struct process_s * process, vpn_t base, vpn_t size ); /********************************************************************************************* * This function allocates memory for a vseg descriptor, initialises it, and register it * in the VMM of the process. It checks the collision with pre-existing vsegs in VMM. * For STACK and MMAP types vseg, it does not use the base argument, but uses the VMM STACK * and MMAP specific allocators to get a base address in virtual space. * To comply with the "on-demand" paging policy, this function does NOT modify the * page table, and does not allocate physical memory for vseg data. ********************************************************************************************* * @ vmm : pointer on process descriptor. * @ base : vseg base address * @ size : vseg size (bytes) * @ type : vseg type * @ returns pointer on vseg if success / returns NULL if no memory or conflict. ********************************************************************************************/ vseg_t * vmm_create_vseg( struct process_s * process, intptr_t base, intptr_t size, uint32_t type ); /********************************************************************************************* * This function removes a vseg identified by it's pointer from the VMM of the calling process. * - If the vseg has not the STACK or MMAP type, it is removed from the vsegs list, * and the physical memory allocated to vseg descriptor is released to KMEM. * - If the vseg has the STACK type, it is removed from the vsegs list, the physical memory * allocated to vseg descriptor is released to KMEM, and the stack slot is returned to the * VMM STACK allocator. * - If the vseg has the MMAP type, it is removed from the vsegs list and is registered * in the zombi_list of the VMM MMAP allocator for future reuse. The physical memory * allocated to vseg descriptor is NOT released to KMEM. ********************************************************************************************* * @ vseg : pointer on vseg to be removed. ********************************************************************************************/ void vmm_remove_vseg( vseg_t * vseg ); /********************************************************************************************* * This function allocates physical memory from the local cluster to map all PTEs * of a "kernel" vseg (type KCODE , KDATA, or KDEV) in the page table of process_zero. * WARNING : It should not be used for "user" vsegs, that must be mapped using the * "on-demand-paging" policy. ********************************************************************************************* * @ vseg : pointer on the vseg to be mapped. * @ attr : GPT attributes to be set for all vseg pages. * @ returns 0 if success / returns ENOMEM if no memory ********************************************************************************************/ error_t vmm_map_kernel_vseg( vseg_t * vseg, uint32_t attr ); /********************************************************************************************* * This function unmaps all PTEs of a given vseg, in the generic page table associated * to a given process descriptor, and releases the corresponding physical memory. * It can be used for any type of vseg. ********************************************************************************************* * @ process : pointer on process descriptor. * @ vseg : pointer on the vseg to be unmapped. ********************************************************************************************/ void vmm_unmap_vseg( struct process_s * process, vseg_t * vseg ); /********************************************************************************************* * This function removes a given region (defined by a base address and a size) from * the VMM of a given process descriptor. This can modify several vsegs: * (a) if the region is not entirely mapped in an existing vseg, it's an error. * (b) if the region has same base and size as an existing vseg, the vseg is removed. * (c) if the removed region cut the vseg in two parts, it is removed and re-created. * (d) if the removed region cut the vseg in three parts, it is removed, and two are created. * TODO : cases (c) and (d) are not implemented [AG] ********************************************************************************************* * @ process : pointer on process descriptor * @ base : vseg base address * @ size : vseg size (bytes) ********************************************************************************************/ error_t vmm_resize_vseg( struct process_s * process, intptr_t base, intptr_t size ); /********************************************************************************************* * This function searches if a given virtual address is contained in a vseg registered in * the local process VMM and returns the vseg pointer if success. ********************************************************************************************* * @ process : pointer on process descriptor * @ vaddr : virtual address * @ returns the pointer on vseg if success / returns NULL if failure. *********************************************************************************************/ vseg_t * vmm_get_vseg( struct process_s * process, intptr_t vaddr ); /********************************************************************************************* * This function is called by the generic exception handler when a page fault * has been detected in a given cluster. * If the local cluster is not the reference cluster, it send a RPC_VMM_GET_PTE * to the reference cluster to get the missing PTE attributes and PPN, and update * the local page table. If the local cluster is the reference, it call directly * the vmm_get_pte() function. ********************************************************************************************* * @ process : pointer on process descriptor. * @ vseg : pointer on involved vseg. * @ vpn : VPN of the missing PTE. * @ returns 0 if success / returns ENOMEM if no memory. ********************************************************************************************/ error_t vmm_handle_page_fault( struct process_s * process, vseg_t * vseg, vpn_t vpn ); /********************************************************************************************* * This function returns in the "attr" and "ppn" arguments the PTE associated to a given * VPN for a given process. This function must be called by a thread running in the * reference cluster. To get the PTE from another cluster, use the RPC_VMM_GET_PTE. * The vseg containing the searched VPN should be registered in the reference VMM. * If the PTE in the reference page table is unmapped, this function allocates the missing * physical page from the target cluster defined by the vseg type, initilize it, * and update the reference page table. It calls the RPC_PMEM_GET_PAGES to get and * initialize the missing physical page, if the target cluster is not the reference cluster. ********************************************************************************************* * @ process : [in] pointer on process descriptor. * @ vpn : [in] VPN defining the missing PTE. * @ attr : [out] PTE attributes. * @ ppn : [out] PTE ppn. * @ returns 0 if success / returns ENOMEM if error. ********************************************************************************************/ error_t vmm_get_pte( struct process_s * process, vpn_t vpn, uint32_t * attr, ppn_t * ppn ); /********************************************************************************************* * This function is called by the vmm_get_pte() function. * Depending on the vseg type, defined by the argument, it returns the PPN * (Physical Page Number) associated to a missing page defined by the argument. * - For the VSEG_TYPE_FILE, it returns the physical page from the file mapper. * For all other types, it allocates a new physical page from the cluster defined * by the cxy> field, or by the MSB bits for a distributed vseg. * - For the VSEG_TYPE_CODE and VSEG_TYPE_DATA types, the allocated page is initialized * from the .elf file mapper. For others vseg types it is not initialised. ********************************************************************************************* * @ vseg : local pointer on vseg containing the mising page. * @ vpn : Virtual Page Number identifying the missing page. * @ ppn : [out] returned Physical Page Number. ********************************************************************************************/ error_t vmm_get_one_ppn( vseg_t * vseg, vpn_t vpn, ppn_t * ppn ); /********************************************************************************************* * This function makes the virtual to physical address translation, using the calling * process page table. It uses identity mapping if required by the argument. * This address translation is required to configure the peripherals having a DMA * capability, or to implement the software L2/L3 cache cohérence, using the MMC device * synchronisation primitives. * WARNING : the value must be defined by the CONFIG_KERNEL_IDENTITY_MAP parameter. ********************************************************************************************* * @ ident : [in] uses identity mapping if true. * @ ptr : [in] virtual address. * @ paddr : [out] pointer on buffer for physical address. * @ returns 0 if success / returns ENOMEM if error. ********************************************************************************************/ error_t vmm_v2p_translate( bool_t ident, void * ptr, paddr_t * paddr ); /********************************************************************************************* ********************************************************************************************/ int sys_madvise( void * start, uint32_t length, uint32_t advice ); /********************************************************************************************* ********************************************************************************************/ int sys_sbrk( uint32_t current_heap_ptr, uint32_t size ); /********************************************************************************************* ********************************************************************************************/ error_t vmm_sbrk( vmm_t * vmm, uint32_t current, uint32_t size ); /********************************************************************************************* ********************************************************************************************/ error_t vmm_madvise_migrate( vmm_t * vmm, uint32_t start, uint32_t len ); /********************************************************************************************* ********************************************************************************************/ error_t vmm_madvise_willneed( vmm_t * vmm, uint32_t start, uint32_t len ); /********************************************************************************************* ********************************************************************************************/ error_t vmm_set_auto_migrate( vmm_t * vmm, uint32_t start, uint32_t flags ); /********************************************************************************************* * Hypothesis: the region is shared-anon, mapper list is rdlocked, page is locked ********************************************************************************************/ error_t vmm_broadcast_inval( vseg_t * region, page_t * page, page_t ** new ); /********************************************************************************************* * Hypothesis: the region is shared-anon, mapper list is rdlocked, page is locked ********************************************************************************************/ error_t vmm_migrate_shared_page_seq( vseg_t * region, page_t * page, page_t ** new ); #endif /* _VMM_H_ */