/* * Copyright (c) 2015-2019 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <svm/ssvm.h> #include <svm/svm_common.h> typedef int (*init_fn) (ssvm_private_t *); typedef void (*delete_fn) (ssvm_private_t *); static init_fn server_init_fns[SSVM_N_SEGMENT_TYPES] = { ssvm_server_init_shm, ssvm_server_init_memfd, ssvm_server_init_private }; static init_fn client_init_fns[SSVM_N_SEGMENT_TYPES] = { ssvm_client_init_shm, ssvm_client_init_memfd, ssvm_client_init_private }; static delete_fn delete_fns[SSVM_N_SEGMENT_TYPES] = { ssvm_delete_shm, ssvm_delete_memfd, ssvm_delete_private }; int ssvm_server_init_shm (ssvm_private_t * ssvm) { int ssvm_fd; u8 junk = 0, *ssvm_filename; ssvm_shared_header_t *sh; uword page_size, requested_va = 0; void *oldheap; if (ssvm->ssvm_size == 0) return SSVM_API_ERROR_NO_SIZE; if (CLIB_DEBUG > 1) clib_warning ("[%d] creating segment '%s'", getpid (), ssvm->name); ASSERT (vec_c_string_is_terminated (ssvm->name)); ssvm_filename = format (0, "/dev/shm/%s%c", ssvm->name, 0); unlink ((char *) ssvm_filename); vec_free (ssvm_filename); ssvm_fd = shm_open ((char *) ssvm->name, O_RDWR | O_CREAT | O_EXCL, 0777); if (ssvm_fd < 0) { clib_unix_warning ("create segment '%s'", ssvm->name); return SSVM_API_ERROR_CREATE_FAILURE; } if (fchmod (ssvm_fd, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP) < 0) clib_unix_warning ("ssvm segment chmod"); if (svm_get_root_rp ()) { /* TODO: is this really needed? */ svm_main_region_t *smr = svm_get_root_rp ()->data_base; if (fchown (ssvm_fd, smr->uid, smr->gid) < 0) clib_unix_warning ("ssvm segment chown"); } if (lseek (ssvm_fd, ssvm->ssvm_size, SEEK_SET) < 0) { clib_unix_warning ("lseek"); close (ssvm_fd); return SSVM_API_ERROR_SET_SIZE; } if (write (ssvm_fd, &junk, 1) != 1) { clib_unix_warning ("set ssvm size"); close (ssvm_fd); return SSVM_API_ERROR_SET_SIZE; } page_size = clib_mem_get_fd_page_size (ssvm_fd); if (ssvm->requested_va) { requested_va = ssvm->requested_va; clib_mem_vm_randomize_va (&requested_va, min_log2 (page_size)); } sh = clib_mem_vm_map_shared (uword_to_pointer (requested_va, void *), ssvm->ssvm_size, ssvm_fd, 0, (char *) ssvm->name); if (sh == CLIB_MEM_VM_MAP_FAILED) { clib_unix_warning ("mmap"); close (ssvm_fd); return SSVM_API_ERROR_MMAP; } close (ssvm_fd); CLIB_MEM_UNPOISON (sh, sizeof (*sh)); sh->server_pid = ssvm->my_pid; sh->ssvm_size = ssvm->ssvm_size; sh->ssvm_va = pointer_to_uword (sh); sh->type = SSVM_SEGMENT_SHM; sh->heap = clib_mem_create_heap (((u8 *) sh) + page_size, ssvm->ssvm_size - page_size, 1 /* locked */ , "ssvm server shm"); oldheap = ssvm_push_heap (sh); sh->name = format (0, "%s", ssvm->name, 0); ssvm_pop_heap (oldheap); ssvm->sh = sh; ssvm->my_pid = getpid (); ssvm->is_server = 1; /* The application has to set set sh->ready... */ return 0; } int ssvm_client_init_shm (ssvm_private_t * ssvm) { struct stat stat; int ssvm_fd = -1; ssvm_shared_header_t *sh; ASSERT (vec_c_string_is_terminated (ssvm->name)); ssvm->is_server = 0; while (ssvm->attach_timeout-- > 0) { if (ssvm_fd < 0) ssvm_fd = shm_open ((char *) ssvm->name, O_RDWR, 0777); if (ssvm_fd < 0) { sleep (1); continue; } if (fstat (ssvm_fd, &stat) < 0) { sleep (1); continue; } if (stat.st_size > 0) goto map_it; } clib_warning ("client timeout"); return SSVM_API_ERROR_CLIENT_TIMEOUT; map_it: sh = (void *) mmap (0, MMAP_PAGESIZE, PROT_READ | PROT_WRITE, MAP_SHARED, ssvm_fd, 0); if (sh == MAP_FAILED) { clib_unix_warning ("client research mmap"); close (ssvm_fd); return SSVM_API_ERROR_MMAP; } while (ssvm->attach_timeout-- > 0) { if (sh->ready) goto re_map_it; } close (ssvm_fd); munmap (sh, MMAP_PAGESIZE); clib_warning ("client timeout 2"); return SSVM_API_ERROR_CLIENT_TIMEOUT; re_map_it: ssvm->requested_va = sh->ssvm_va; ssvm->ssvm_size = sh->ssvm_size; munmap (sh, MMAP_PAGESIZE); sh = ssvm->sh = (void *) mmap ((void *) ssvm->requested_va, ssvm->ssvm_size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, ssvm_fd, 0); if (sh == MAP_FAILED) { clib_unix_warning ("client final mmap"); close (ssvm_fd); return SSVM_API_ERROR_MMAP; } sh->client_pid = getpid (); return 0; } void ssvm_delete_shm (ssvm_private_t * ssvm) { u8 *fn; fn = format (0, "/dev/shm/%s%c", ssvm->name, 0); if (CLIB_DEBUG > 1) clib_warning ("[%d] unlinking ssvm (%s) backing file '%s'", getpid (), ssvm->name, fn); /* Throw away the backing file */ if (unlink ((char *) fn) < 0) clib_unix_warning ("unlink segment '%s'", ssvm->name); vec_free (fn); vec_free (ssvm->name); if (ssvm->is_server) clib_mem_vm_unmap (ssvm->sh); else munmap ((void *) ssvm->sh, ssvm->ssvm_size); } /** * Initialize memfd segment server */ int ssvm_server_init_memfd (ssvm_private_t * memfd) { uword page_size, n_pages; ssvm_shared_header_t *sh; int log2_page_size; void *oldheap; if (memfd->ssvm_size == 0) return SSVM_API_ERROR_NO_SIZE; ASSERT (vec_c_string_is_terminated (memfd->name)); memfd->fd = clib_mem_vm_create_fd (CLIB_MEM_PAGE_SZ_DEFAULT, (char *) memfd->name); if (memfd->fd == CLIB_MEM_ERROR) { clib_unix_warning ("failed to create memfd"); return SSVM_API_ERROR_CREATE_FAILURE; } log2_page_size = clib_mem_get_fd_log2_page_size (memfd->fd); if (log2_page_size == 0) { clib_unix_warning ("cannot determine page size"); return SSVM_API_ERROR_CREATE_FAILURE; } n_pages = ((memfd->ssvm_size - 1) >> log2_page_size) + 1; if ((ftruncate (memfd->fd, n_pages << log2_page_size)) == -1) { clib_unix_warning ("memfd ftruncate failure"); return SSVM_API_ERROR_CREATE_FAILURE; } sh = clib_mem_vm_map_shared (uword_to_pointer (memfd->requested_va, void *), memfd->ssvm_size, memfd->fd, 0, (char *) memfd->name); if (sh == CLIB_MEM_VM_MAP_FAILED) { clib_unix_warning ("memfd map (fd %d)", memfd->fd); close (memfd->fd); return SSVM_API_ERROR_CREATE_FAILURE; } memfd->sh = sh; memfd->my_pid = getpid (); memfd->is_server = 1; sh->server_pid = memfd->my_pid; sh->ssvm_size = memfd->ssvm_size; sh->ssvm_va = pointer_to_uword (sh); sh->type = SSVM_SEGMENT_MEMFD; page_size = 1ULL << log2_page_size; sh->heap = clib_mem_create_heap (((u8 *) sh) + page_size, memfd->ssvm_size - page_size, 1 /* locked */ , "ssvm server memfd"); oldheap = ssvm_push_heap (sh); sh->name = format (0, "%s", memfd->name, 0); ssvm_pop_heap (oldheap); /* The application has to set set sh->ready... */ return 0; } /** * Initialize memfd segment client * * Subtly different than svm_client_init. The caller needs to acquire * a usable file descriptor for the memfd segment e.g. via * vppinfra/socket.c:default_socket_recvmsg */ int ssvm_client_init_memfd (ssvm_private_t * memfd) { int mmap_flags = MAP_SHARED; ssvm_shared_header_t *sh; uword page_size; memfd->is_server = 0; page_size = clib_mem_get_fd_page_size (memfd->fd); if (!page_size) { clib_unix_warning ("page size unknown"); return SSVM_API_ERROR_MMAP; } /* * Map the segment once, to look at the shared header */ sh = (void *) mmap (0, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, memfd->fd, 0); if (sh == MAP_FAILED) { clib_unix_warning ("client research mmap (fd %d)", memfd->fd); close (memfd->fd); return SSVM_API_ERROR_MMAP; } memfd->requested_va = sh->ssvm_va; memfd->ssvm_size = sh->ssvm_size; munmap (sh, page_size); if (memfd->requested_va) mmap_flags |= MAP_FIXED; /* * Remap the segment at the 'right' address */ sh = (void *) mmap (uword_to_pointer (memfd->requested_va, void *), memfd->ssvm_size, PROT_READ | PROT_WRITE, mmap_flags, memfd->fd, 0); if (sh == MAP_FAILED) { clib_unix_warning ("client final mmap"); close (memfd->fd); return SSVM_API_ERROR_MMAP; } sh->client_pid = getpid (); memfd->sh = sh; return 0; } void ssvm_delete_memfd (ssvm_private_t * memfd) { vec_free (memfd->name); if (memfd->is_server) clib_mem_vm_unmap (memfd->sh); else munmap (memfd->sh, memfd->ssvm_size); close (memfd->fd); } /** * Initialize segment in a private heap */ int ssvm_server_init_private (ssvm_private_t * ssvm) { uword page_size, log2_page_size, rnd_size = 0; ssvm_shared_header_t *sh; clib_mem_heap_t *heap, *oldheap; log2_page_size = clib_mem_get_log2_page_size (); if (log2_page_size == 0) { clib_unix_warning ("cannot determine page size"); return SSVM_API_ERROR_CREATE_FAILURE; } page_size = 1ULL << log2_page_size; rnd_size = clib_max (ssvm->ssvm_size + (page_size - 1), ssvm->ssvm_size); rnd_size &= ~(page_size - 1); sh = clib_mem_vm_map (0, rnd_size + page_size, log2_page_size, (char *) ssvm->name); if (sh == CLIB_MEM_VM_MAP_FAILED) { clib_unix_warning ("private map failed"); return SSVM_API_ERROR_CREATE_FAILURE; } heap = clib_mem_create_heap ((u8 *) sh + page_size, rnd_size, 1 /* locked */ , "ssvm server private"); if (heap == 0) { clib_unix_warning ("heap alloc"); return -1; } rnd_size = clib_mem_get_heap_free_space (heap); ssvm->ssvm_size = rnd_size; ssvm->is_server = 1; ssvm->my_pid = getpid (); ssvm->requested_va = ~0; /* First page in allocated memory is set aside for the shared header */ ssvm->sh = sh; clib_memset (sh, 0, sizeof (*sh)); sh->heap = heap; sh->ssvm_size = rnd_size; sh->ssvm_va = pointer_to_uword (sh); sh->type = SSVM_SEGMENT_PRIVATE; oldheap = ssvm_push_heap (sh); sh->name = format (0, "%s", ssvm->name, 0); ssvm_pop_heap (oldheap); return 0; } int ssvm_client_init_private (ssvm_private_t * ssvm) { clib_warning ("BUG: this should not be called!"); return -1; } void ssvm_delete_private (ssvm_private_t * ssvm) { vec_free (ssvm->name); clib_mem_destroy_heap (ssvm->sh->heap); clib_mem_vm_unmap (ssvm->sh); } int ssvm_server_init (ssvm_private_t * ssvm, ssvm_segment_type_t type) { return (server_init_fns[type]) (ssvm); } int ssvm_client_init (ssvm_private_t * ssvm, ssvm_segment_type_t type) { return (client_init_fns[type]) (ssvm); } void ssvm_delete (ssvm_private_t * ssvm) { delete_fns[ssvm->sh->type] (ssvm); } ssvm_segment_type_t ssvm_type (const ssvm_private_t * ssvm) { return ssvm->sh->type; } u8 * ssvm_name (const ssvm_private_t * ssvm) { return ssvm->sh->name; } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */