diff options
Diffstat (limited to 'sys/vm/vm_map.c')
| -rw-r--r-- | sys/vm/vm_map.c | 540 |
1 files changed, 0 insertions, 540 deletions
diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c deleted file mode 100644 index ca1d18a..0000000 --- a/sys/vm/vm_map.c +++ /dev/null @@ -1,540 +0,0 @@ -/* - * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team. - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are met: - * - * 1. Redistributions of source code must retain the above copyright notice, - * this list of conditions and the following disclaimer. - * 2. 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. - * 3. Neither the name of Hyra nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER OR CONTRIBUTORS 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. - */ - -#include <vm/map.h> -#include <vm/vm.h> -#include <vm/pmap.h> -#include <vm/physseg.h> -#include <vm/dynalloc.h> -#include <vm/pager.h> -#include <sys/types.h> -#include <sys/filedesc.h> -#include <sys/cdefs.h> -#include <sys/panic.h> -#include <sys/sched.h> -#include <lib/assert.h> - -#define ALLOC_MAPPING() dynalloc(sizeof(struct vm_mapping)) -#define DESTROY_MAPPING(MAPPING) dynfree(MAPPING) -#define MMAP_DEFAULT_OFF 0x3000000 - -static size_t -vm_hash_vaddr(vaddr_t va) { - va = (va ^ (va >> 30)) * (size_t)0xBF58476D1CE4E5B9; - va = (va ^ (va >> 27)) * (size_t)0x94D049BB133111EB; - va = va ^ (va >> 31); - return va; -} - -/* - * Fetches a suitable offset to be added to an - * address that will be mapped with mmap() to - * avoid clobbering the address space. - */ -static uintptr_t -vm_get_mapoff(struct proc *td) -{ - /* - * FIXME: For now we are adding a fixed offset to the - * address to be mapped. - * - * It would be best to ensure that it isn't in - * range of the process *just in case*. - */ - (void)td; - return MMAP_DEFAULT_OFF; -} - -/* - * Destroy a map queue. - */ -void -vm_free_mapq(vm_mapq_t *mapq) -{ - struct vm_mapping *map; - size_t map_pages, granule; - - granule = vm_get_page_size(); - TAILQ_FOREACH(map, mapq, link) { - map_pages = (map->range.end - map->range.start) / granule; - vm_free_pageframe(map->range.start, map_pages); - } - dynfree(map); -} - -/* - * Remove a mapping from a mapspace. - * - * @ms: Mapspace. - * @mapping: Mapping to remove. - */ -void -vm_mapspace_remove(struct vm_mapspace *ms, struct vm_mapping *mapping) -{ - size_t vhash; - vm_mapq_t *mapq; - - if (ms == NULL) - return; - - vhash = vm_hash_vaddr(mapping->range.start); - mapq = &ms->mtab[vhash % MTAB_ENTRIES]; - TAILQ_REMOVE(mapq, mapping, link); - --ms->map_count; -} - -/* - * Fetch a mapping from a mapspace. - * - * @ms: Mapspace. - * @va: Virtual address. - */ -struct vm_mapping * -vm_mapping_fetch(struct vm_mapspace *ms, vaddr_t va) -{ - size_t vhash; - const vm_mapq_t *mapq; - struct vm_mapping *map; - - if (ms == NULL) - return NULL; - - vhash = vm_hash_vaddr(va); - mapq = &ms->mtab[vhash % MTAB_ENTRIES]; - - TAILQ_FOREACH(map, mapq, link) { - if (map->vhash == vhash) { - return map; - } - } - - return NULL; -} - -/* - * Insert a mapping into a mapspace. - * - * @ms: Target mapspace. - * @mapping: Mapping to insert. - */ -void -vm_mapspace_insert(struct vm_mapspace *ms, struct vm_mapping *mapping) -{ - size_t vhash; - vm_mapq_t *q; - - if (mapping == NULL || ms == NULL) - return; - - vhash = vm_hash_vaddr(mapping->range.start); - mapping->vhash = vhash; - - q = &ms->mtab[vhash % MTAB_ENTRIES]; - TAILQ_INSERT_HEAD(q, mapping, link); - ++ms->map_count; -} - -/* - * Create a mapping (internal helper) - * - * @addr: Address to map. - * @physmem: Physical address, set to 0 to alloc one here - * @prot: Protection flags. - * - * Returns zero on failure. - */ -static paddr_t -vm_map(void *addr, paddr_t physmem, vm_prot_t prot, size_t len) -{ - struct proc *td = this_td(); - const size_t GRANULE = vm_get_page_size(); - - int status; - - /* Allocate the physical memory if needed */ - if (physmem == 0) - physmem = vm_alloc_pageframe(len / GRANULE); - - if (physmem == 0) - return 0; - - /* - * XXX: There is no need to worry about alignment yet - * as vm_map_create() handles that internally. - */ - prot |= PROT_USER; - status = vm_map_create(td->addrsp, (vaddr_t)addr, physmem, prot, len); - if (status != 0) { - vm_free_pageframe(physmem, len / GRANULE); - return 0; - } - - return physmem; -} - -/* - * Create a mapping backed by a file. - * - * @addr: Address to map. - * @prot: Protection flags. - * @len: Length of mapping. - * @off: Offset. - * @fd: File descriptor. - */ -static paddr_t -vm_fd_map(void *addr, vm_prot_t prot, size_t len, off_t off, int fd, - struct vm_mapping *mapping) -{ - paddr_t physmem = 0; - - int oflag; - struct filedesc *filedes; - struct vnode *vp; - - struct proc *td = this_td(); - struct vm_page pg = {0}; - - /* Attempt to get the vnode */ - filedes = fd_from_fdnum(td, fd); - if (filedes == NULL) - return 0; - if ((vp = filedes->vnode) == NULL) - return 0; - - /* Check the perms of the filedes */ - oflag = filedes->oflag; - if (__TEST(prot, PROT_WRITE) && oflag == O_RDONLY) - return 0; - if (!__TEST(prot, PROT_WRITE) && oflag == O_WRONLY) - return 0; - - /* Try to create the virtual memory object */ - if (vm_obj_init(&vp->vmobj, vp) != 0) - return 0; - - mapping->vmobj = vp->vmobj; - vm_object_ref(vp->vmobj); - - /* Try to fetch a physical address */ - if (vm_pager_paddr(vp->vmobj, &physmem, prot) != 0) { - vm_obj_destroy(vp->vmobj); - return 0; - } - - /* - * If the pager found a physical address for the object to - * be mapped to, then we start off with an anonymous mapping - * then connect it to the physical address (creates a shared mapping) - */ - if (physmem != 0) { - vm_map(addr, physmem, prot, len); - return physmem; - } - - /* - * If the pager could not find a physical address for - * the object to be mapped to, start of with just a plain - * anonymous mapping then page-in from whatever filesystem - * (creates a shared mapping) - */ - physmem = vm_map(addr, 0, prot, len); - pg.physaddr = physmem; - - if (vm_pager_get(vp->vmobj, off, len, &pg) != 0) { - vm_obj_destroy(vp->vmobj); - return 0; - } - - return physmem; -} - -static int -munmap(void *addr, size_t len) -{ - struct proc *td = this_td(); - struct vm_mapping *mapping; - struct vm_object *obj; - - struct vm_mapspace *ms; - size_t map_len, granule; - vaddr_t map_start, map_end; - - ms = &td->mapspace; - - granule = vm_get_page_size(); - mapping = vm_mapping_fetch(ms, (vaddr_t)addr); - if (mapping == NULL) { - return -1; - } - - spinlock_acquire(&td->mapspace_lock); - map_start = mapping->range.start; - map_end = mapping->range.end; - map_len = map_end - map_start; - - /* Try to release any virtual memory objects */ - if ((obj = mapping->vmobj) != NULL) { - /* - * Drop our ref and try to cleanup. If the refcount - * is > 0, something is still holding it and we can't - * do much. - */ - vm_object_unref(obj); - if (obj->ref == 0) { - vm_obj_destroy(obj); - } - } - - /* Release the mapping */ - vm_map_destroy(td->addrsp, map_start, map_len); - vm_free_pageframe(mapping->range.start, map_len / granule); - - /* Destroy the mapping descriptor */ - vm_mapspace_remove(ms, mapping); - dynfree(mapping); - spinlock_release(&td->mapspace_lock); - return 0; -} - -static void * -mmap(void *addr, size_t len, int prot, int flags, int fildes, off_t off) -{ - const int PROT_MASK = PROT_WRITE | PROT_EXEC; - const size_t GRANULE = vm_get_page_size(); - uintptr_t map_end, map_start; - - struct proc *td = this_td(); - struct vm_mapping *mapping; - struct vm_object *vmobj; - - size_t misalign = ((vaddr_t)addr) & (GRANULE - 1); - off_t mapoff = vm_get_mapoff(td); - - paddr_t physmem = 0; - vaddr_t va = (vaddr_t)addr + mapoff; - - /* Ensure of valid prot flags */ - if ((prot & ~PROT_MASK) != 0) - return MAP_FAILED; - - /* Try to allocate a mapping */ - mapping = ALLOC_MAPPING(); - if (mapping == NULL) - return MAP_FAILED; - - /* Setup prot and mapping start */ - mapping->prot = prot | PROT_USER; - map_start = __ALIGN_DOWN(va, GRANULE); - - /* Ensure the length is aligned */ - len = __ALIGN_UP(len + misalign, GRANULE); - - /* - * Now we check what type of map request - * this is. - */ - if (__TEST(flags, MAP_ANONYMOUS)) { - /* Try to create a virtual memory object */ - if (vm_obj_init(&vmobj, NULL) != 0) - goto fail; - - /* - * If 'addr' is NULL, we'll just allocate physical - * memory right away. - */ - if (addr == NULL) - physmem = vm_alloc_pageframe(len / GRANULE); - - /* - * Enable demand paging for this object if - * `addr` is not NULL. - */ - if (addr != NULL) { - vmobj->is_anon = 1; - vmobj->demand = 1; - - mapping->vmobj = vmobj; - mapping->physmem_base = 0; - } else if (addr == NULL && physmem != 0) { - map_start = physmem + mapoff; - vm_map((void *)map_start, physmem, prot, len); - addr = (void *)physmem; - - vmobj->is_anon = 1; - vmobj->demand = 0; - mapping->vmobj = vmobj; - mapping->physmem_base = physmem; - } - - /* Did this work? */ - if (physmem == 0 && addr == NULL) { - goto fail; - } - } else if (__TEST(flags, MAP_SHARED)) { - physmem = vm_fd_map((void *)map_start, prot, len, off, fildes, mapping); - if (physmem == 0) { - goto fail; - } - } - - /* Setup map_end and map ranges */ - map_end = map_start + len; - mapping->range.start = map_start; - mapping->range.end = map_end; - mapping->physmem_base = physmem; - - /* Add to mapspace */ - spinlock_acquire(&td->mapspace_lock); - vm_mapspace_insert(&td->mapspace, mapping); - spinlock_release(&td->mapspace_lock); - return (void *)map_start; -fail: - DESTROY_MAPPING(mapping); - return MAP_FAILED; -} - -/* - * Internal routine for cleaning up. - * - * @va: VA to start unmapping at. - * @bytes_aligned: Amount of bytes to unmap. - * - * XXX DANGER!!: `bytes_aligned' is expected to be aligned by the - * machine's page granule. If this is not so, - * undefined behaviour will occur. This will - * be enforced via a panic. - */ -static void -vm_map_cleanup(struct vas vas, struct vm_ctx *ctx, vaddr_t va, - size_t bytes_aligned, size_t granule) -{ - __assert(bytes_aligned != 0); - __assert((bytes_aligned & (granule - 1)) == 0); - - for (size_t i = 0; i < bytes_aligned; i += 0x1000) { - if (pmap_unmap(ctx, vas, va + i) != 0) { - /* - * XXX: This shouldn't happen... If it somehow does, - * then this should be handled. - */ - panic("Could not cleanup!!!\n"); - } - } -} - -/* - * Create a virtual memory mappings in the current - * address space. - * - * @va: Virtual address. - * @pa: Physical address. - * @prot: Protection flags. - * @bytes: Amount of bytes to be mapped. This is aligned by the - * machine's page granule, typically a 4k boundary. - */ -int -vm_map_create(struct vas vas, vaddr_t va, paddr_t pa, vm_prot_t prot, size_t bytes) -{ - size_t granule = vm_get_page_size(); - size_t misalign = va & (granule - 1); - int s; - - struct vm_ctx *ctx = vm_get_ctx(); - - /* - * The amount of bytes to be mapped should fully span pages, - * so we ensure it is aligned by the page granularity. - */ - bytes = __ALIGN_UP(bytes + misalign, granule); - - /* Align VA/PA by granule */ - va = __ALIGN_DOWN(va, granule); - pa = __ALIGN_DOWN(pa, granule); - - if (bytes == 0) { - /* You can't map 0 pages, silly! */ - return -1; - } - - for (uintptr_t i = 0; i < bytes; i += granule) { - s = pmap_map(ctx, vas, va + i, pa + i, prot); - if (s != 0) { - /* Something went a bit wrong here, cleanup */ - vm_map_cleanup(vas, ctx, va, i, bytes); - return -1; - } - } - - return 0; -} - -/* - * Destroy a virtual memory mapping in the current - * address space. - */ -int -vm_map_destroy(struct vas vas, vaddr_t va, size_t bytes) -{ - struct vm_ctx *ctx = vm_get_ctx(); - size_t granule = vm_get_page_size(); - size_t misalign = va & (granule - 1); - int s; - - /* We want bytes to be aligned by the granule */ - bytes = __ALIGN_UP(bytes + misalign, granule); - - /* Align VA by granule */ - va = __ALIGN_DOWN(va, granule); - - if (bytes == 0) { - return -1; - } - - for (uintptr_t i = 0; i < bytes; i += granule) { - s = pmap_unmap(ctx, vas, va + i); - if (s != 0) { - return -1; - } - } - - return 0; -} - -uint64_t -sys_mmap(struct syscall_args *args) -{ - return (uintptr_t)mmap((void *)args->arg0, args->arg1, args->arg2, - args->arg3, args->arg4, args->arg5); -} - -uint64_t -sys_munmap(struct syscall_args *args) -{ - return munmap((void *)args->arg0, args->arg1); -} |