| 0,0 → 1,271 |
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| /* |
| * Copyright (c) 2006 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 genericddi |
| * @{ |
| */ |
| |
| /** |
| * @file |
| * @brief Device Driver Interface functions. |
| * |
| * This file contains functions that comprise the Device Driver Interface. |
| * These are the functions for mapping physical memory and enabling I/O |
| * space to tasks. |
| */ |
| |
| #include <ddi/ddi.h> |
| #include <ddi/ddi_arg.h> |
| #include <proc/task.h> |
| #include <security/cap.h> |
| #include <mm/frame.h> |
| #include <mm/as.h> |
| #include <synch/spinlock.h> |
| #include <syscall/copy.h> |
| #include <adt/btree.h> |
| #include <arch.h> |
| #include <align.h> |
| #include <errno.h> |
| |
| /** This lock protects the parea_btree. */ |
| SPINLOCK_INITIALIZE(parea_lock); |
| |
| /** B+tree with enabled physical memory areas. */ |
| static btree_t parea_btree; |
| |
| /** Initialize DDI. */ |
| void ddi_init(void) |
| { |
| btree_create(&parea_btree); |
| } |
| |
| /** Enable piece of physical memory for mapping by physmem_map(). |
| * |
| * @param parea Pointer to physical area structure. |
| * |
| * @todo This function doesn't check for overlaps. It depends on the kernel to |
| * create disjunct physical memory areas. |
| */ |
| void ddi_parea_register(parea_t *parea) |
| { |
| ipl_t ipl; |
| |
| ipl = interrupts_disable(); |
| spinlock_lock(&parea_lock); |
| |
| /* |
| * TODO: we should really check for overlaps here. |
| * However, we should be safe because the kernel is pretty sane and |
| * memory of different devices doesn't overlap. |
| */ |
| btree_insert(&parea_btree, (btree_key_t) parea->pbase, parea, NULL); |
| |
| spinlock_unlock(&parea_lock); |
| interrupts_restore(ipl); |
| } |
| |
| /** Map piece of physical memory into virtual address space of current task. |
| * |
| * @param pf Physical address of the starting frame. |
| * @param vp Virtual address of the starting page. |
| * @param pages Number of pages to map. |
| * @param flags Address space area flags for the mapping. |
| * |
| * @return 0 on success, EPERM if the caller lacks capabilities to use this |
| * syscall, ENOENT if there is no task matching the specified ID or the |
| * physical address space is not enabled for mapping and ENOMEM if there |
| * was a problem in creating address space area. |
| */ |
| static int ddi_physmem_map(uintptr_t pf, uintptr_t vp, count_t pages, int flags) |
| { |
| ipl_t ipl; |
| cap_t caps; |
| mem_backend_data_t backend_data; |
| |
| backend_data.base = pf; |
| backend_data.frames = pages; |
| |
| /* |
| * Make sure the caller is authorised to make this syscall. |
| */ |
| caps = cap_get(TASK); |
| if (!(caps & CAP_MEM_MANAGER)) |
| return EPERM; |
| |
| ipl = interrupts_disable(); |
| |
| /* |
| * Check if the physical memory area is enabled for mapping. |
| * If the architecture supports virtually indexed caches, intercept |
| * attempts to create an illegal address alias. |
| */ |
| spinlock_lock(&parea_lock); |
| parea_t *parea; |
| btree_node_t *nodep; |
| parea = (parea_t *) btree_search(&parea_btree, (btree_key_t) pf, &nodep); |
| if (!parea || parea->frames < pages || ((flags & AS_AREA_CACHEABLE) && |
| !parea->cacheable) || (!(flags & AS_AREA_CACHEABLE) && |
| parea->cacheable)) { |
| /* |
| * This physical memory area cannot be mapped. |
| */ |
| spinlock_unlock(&parea_lock); |
| interrupts_restore(ipl); |
| return ENOENT; |
| } |
| spinlock_unlock(&parea_lock); |
| |
| spinlock_lock(&TASK->lock); |
| |
| if (!as_area_create(TASK->as, flags, pages * PAGE_SIZE, vp, AS_AREA_ATTR_NONE, |
| &phys_backend, &backend_data)) { |
| /* |
| * The address space area could not have been created. |
| * We report it using ENOMEM. |
| */ |
| spinlock_unlock(&TASK->lock); |
| interrupts_restore(ipl); |
| return ENOMEM; |
| } |
| |
| /* |
| * Mapping is created on-demand during page fault. |
| */ |
| |
| spinlock_unlock(&TASK->lock); |
| interrupts_restore(ipl); |
| return 0; |
| } |
| |
| /** Enable range of I/O space for task. |
| * |
| * @param id Task ID of the destination task. |
| * @param ioaddr Starting I/O address. |
| * @param size Size of the enabled I/O space.. |
| * |
| * @return 0 on success, EPERM if the caller lacks capabilities to use this |
| * syscall, ENOENT if there is no task matching the specified ID. |
| */ |
| static int ddi_iospace_enable(task_id_t id, uintptr_t ioaddr, size_t size) |
| { |
| ipl_t ipl; |
| cap_t caps; |
| task_t *t; |
| int rc; |
| |
| /* |
| * Make sure the caller is authorised to make this syscall. |
| */ |
| caps = cap_get(TASK); |
| if (!(caps & CAP_IO_MANAGER)) |
| return EPERM; |
| |
| ipl = interrupts_disable(); |
| spinlock_lock(&tasks_lock); |
| |
| t = task_find_by_id(id); |
| |
| if ((!t) || (!context_check(CONTEXT, t->context))) { |
| /* |
| * There is no task with the specified ID |
| * or the task belongs to a different security |
| * context. |
| */ |
| spinlock_unlock(&tasks_lock); |
| interrupts_restore(ipl); |
| return ENOENT; |
| } |
| |
| /* Lock the task and release the lock protecting tasks_btree. */ |
| spinlock_lock(&t->lock); |
| spinlock_unlock(&tasks_lock); |
| |
| rc = ddi_iospace_enable_arch(t, ioaddr, size); |
| |
| spinlock_unlock(&t->lock); |
| interrupts_restore(ipl); |
| return rc; |
| } |
| |
| /** Wrapper for SYS_PHYSMEM_MAP syscall. |
| * |
| * @param phys_base Physical base address to map |
| * @param virt_base Destination virtual address |
| * @param pages Number of pages |
| * @param flags Flags of newly mapped pages |
| * |
| * @return 0 on success, otherwise it returns error code found in errno.h |
| */ |
| unative_t sys_physmem_map(unative_t phys_base, unative_t virt_base, |
| unative_t pages, unative_t flags) |
| { |
| return (unative_t) ddi_physmem_map(ALIGN_DOWN((uintptr_t) phys_base, |
| FRAME_SIZE), ALIGN_DOWN((uintptr_t) virt_base, PAGE_SIZE), |
| (count_t) pages, (int) flags); |
| } |
| |
| /** Wrapper for SYS_ENABLE_IOSPACE syscall. |
| * |
| * @param uspace_io_arg User space address of DDI argument structure. |
| * |
| * @return 0 on success, otherwise it returns error code found in errno.h |
| */ |
| unative_t sys_iospace_enable(ddi_ioarg_t *uspace_io_arg) |
| { |
| ddi_ioarg_t arg; |
| int rc; |
| |
| rc = copy_from_uspace(&arg, uspace_io_arg, sizeof(ddi_ioarg_t)); |
| if (rc != 0) |
| return (unative_t) rc; |
| |
| return (unative_t) ddi_iospace_enable((task_id_t) arg.task_id, |
| (uintptr_t) arg.ioaddr, (size_t) arg.size); |
| } |
| |
| /** Disable or enable preemption. |
| * |
| * @param enable If non-zero, the preemption counter will be decremented, |
| * leading to potential enabling of preemption. Otherwise the preemption |
| * counter will be incremented, preventing preemption from occurring. |
| * |
| * @return Zero on success or EPERM if callers capabilities are not sufficient. |
| */ |
| unative_t sys_preempt_control(int enable) |
| { |
| if (!cap_get(TASK) & CAP_PREEMPT_CONTROL) |
| return EPERM; |
| if (enable) |
| preemption_enable(); |
| else |
| preemption_disable(); |
| return 0; |
| } |
| |
| /** @} |
| */ |