1fd7f0d66SPaolo Bonzini /* 2fd7f0d66SPaolo Bonzini * Generic FIFO component, implemented as a circular buffer. 3fd7f0d66SPaolo Bonzini * 4fd7f0d66SPaolo Bonzini * Copyright (c) 2012 Peter A. G. Crosthwaite 5fd7f0d66SPaolo Bonzini * 6fd7f0d66SPaolo Bonzini * This program is free software; you can redistribute it and/or 7fd7f0d66SPaolo Bonzini * modify it under the terms of the GNU General Public License 8fd7f0d66SPaolo Bonzini * as published by the Free Software Foundation; either version 9fd7f0d66SPaolo Bonzini * 2 of the License, or (at your option) any later version. 10fd7f0d66SPaolo Bonzini * 11fd7f0d66SPaolo Bonzini * You should have received a copy of the GNU General Public License along 12fd7f0d66SPaolo Bonzini * with this program; if not, see <http://www.gnu.org/licenses/>. 13fd7f0d66SPaolo Bonzini */ 14fd7f0d66SPaolo Bonzini 15aafd7584SPeter Maydell #include "qemu/osdep.h" 16*d6454270SMarkus Armbruster #include "migration/vmstate.h" 17fd7f0d66SPaolo Bonzini #include "qemu/fifo8.h" 18fd7f0d66SPaolo Bonzini 19fd7f0d66SPaolo Bonzini void fifo8_create(Fifo8 *fifo, uint32_t capacity) 20fd7f0d66SPaolo Bonzini { 21fd7f0d66SPaolo Bonzini fifo->data = g_new(uint8_t, capacity); 22fd7f0d66SPaolo Bonzini fifo->capacity = capacity; 23fd7f0d66SPaolo Bonzini fifo->head = 0; 24fd7f0d66SPaolo Bonzini fifo->num = 0; 25fd7f0d66SPaolo Bonzini } 26fd7f0d66SPaolo Bonzini 27fd7f0d66SPaolo Bonzini void fifo8_destroy(Fifo8 *fifo) 28fd7f0d66SPaolo Bonzini { 29fd7f0d66SPaolo Bonzini g_free(fifo->data); 30fd7f0d66SPaolo Bonzini } 31fd7f0d66SPaolo Bonzini 32fd7f0d66SPaolo Bonzini void fifo8_push(Fifo8 *fifo, uint8_t data) 33fd7f0d66SPaolo Bonzini { 34fd7f0d66SPaolo Bonzini if (fifo->num == fifo->capacity) { 35fd7f0d66SPaolo Bonzini abort(); 36fd7f0d66SPaolo Bonzini } 37fd7f0d66SPaolo Bonzini fifo->data[(fifo->head + fifo->num) % fifo->capacity] = data; 38fd7f0d66SPaolo Bonzini fifo->num++; 39fd7f0d66SPaolo Bonzini } 40fd7f0d66SPaolo Bonzini 41c4e57af8SBeniamino Galvani void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num) 42c4e57af8SBeniamino Galvani { 43c4e57af8SBeniamino Galvani uint32_t start, avail; 44c4e57af8SBeniamino Galvani 45c4e57af8SBeniamino Galvani if (fifo->num + num > fifo->capacity) { 46c4e57af8SBeniamino Galvani abort(); 47c4e57af8SBeniamino Galvani } 48c4e57af8SBeniamino Galvani 49c4e57af8SBeniamino Galvani start = (fifo->head + fifo->num) % fifo->capacity; 50c4e57af8SBeniamino Galvani 51c4e57af8SBeniamino Galvani if (start + num <= fifo->capacity) { 52c4e57af8SBeniamino Galvani memcpy(&fifo->data[start], data, num); 53c4e57af8SBeniamino Galvani } else { 54c4e57af8SBeniamino Galvani avail = fifo->capacity - start; 55c4e57af8SBeniamino Galvani memcpy(&fifo->data[start], data, avail); 56c4e57af8SBeniamino Galvani memcpy(&fifo->data[0], &data[avail], num - avail); 57c4e57af8SBeniamino Galvani } 58c4e57af8SBeniamino Galvani 59c4e57af8SBeniamino Galvani fifo->num += num; 60c4e57af8SBeniamino Galvani } 61c4e57af8SBeniamino Galvani 62fd7f0d66SPaolo Bonzini uint8_t fifo8_pop(Fifo8 *fifo) 63fd7f0d66SPaolo Bonzini { 64fd7f0d66SPaolo Bonzini uint8_t ret; 65fd7f0d66SPaolo Bonzini 66fd7f0d66SPaolo Bonzini if (fifo->num == 0) { 67fd7f0d66SPaolo Bonzini abort(); 68fd7f0d66SPaolo Bonzini } 69fd7f0d66SPaolo Bonzini ret = fifo->data[fifo->head++]; 70fd7f0d66SPaolo Bonzini fifo->head %= fifo->capacity; 71fd7f0d66SPaolo Bonzini fifo->num--; 72fd7f0d66SPaolo Bonzini return ret; 73fd7f0d66SPaolo Bonzini } 74fd7f0d66SPaolo Bonzini 75c4e57af8SBeniamino Galvani const uint8_t *fifo8_pop_buf(Fifo8 *fifo, uint32_t max, uint32_t *num) 76c4e57af8SBeniamino Galvani { 77c4e57af8SBeniamino Galvani uint8_t *ret; 78c4e57af8SBeniamino Galvani 79c4e57af8SBeniamino Galvani if (max == 0 || max > fifo->num) { 80c4e57af8SBeniamino Galvani abort(); 81c4e57af8SBeniamino Galvani } 82c4e57af8SBeniamino Galvani *num = MIN(fifo->capacity - fifo->head, max); 83c4e57af8SBeniamino Galvani ret = &fifo->data[fifo->head]; 84c4e57af8SBeniamino Galvani fifo->head += *num; 85c4e57af8SBeniamino Galvani fifo->head %= fifo->capacity; 86c4e57af8SBeniamino Galvani fifo->num -= *num; 87c4e57af8SBeniamino Galvani return ret; 88c4e57af8SBeniamino Galvani } 89c4e57af8SBeniamino Galvani 90fd7f0d66SPaolo Bonzini void fifo8_reset(Fifo8 *fifo) 91fd7f0d66SPaolo Bonzini { 92fd7f0d66SPaolo Bonzini fifo->num = 0; 9358892d47SBeniamino Galvani fifo->head = 0; 94fd7f0d66SPaolo Bonzini } 95fd7f0d66SPaolo Bonzini 96fd7f0d66SPaolo Bonzini bool fifo8_is_empty(Fifo8 *fifo) 97fd7f0d66SPaolo Bonzini { 98fd7f0d66SPaolo Bonzini return (fifo->num == 0); 99fd7f0d66SPaolo Bonzini } 100fd7f0d66SPaolo Bonzini 101fd7f0d66SPaolo Bonzini bool fifo8_is_full(Fifo8 *fifo) 102fd7f0d66SPaolo Bonzini { 103fd7f0d66SPaolo Bonzini return (fifo->num == fifo->capacity); 104fd7f0d66SPaolo Bonzini } 105fd7f0d66SPaolo Bonzini 106c4e57af8SBeniamino Galvani uint32_t fifo8_num_free(Fifo8 *fifo) 107c4e57af8SBeniamino Galvani { 108c4e57af8SBeniamino Galvani return fifo->capacity - fifo->num; 109c4e57af8SBeniamino Galvani } 110c4e57af8SBeniamino Galvani 111c4e57af8SBeniamino Galvani uint32_t fifo8_num_used(Fifo8 *fifo) 112c4e57af8SBeniamino Galvani { 113c4e57af8SBeniamino Galvani return fifo->num; 114c4e57af8SBeniamino Galvani } 115c4e57af8SBeniamino Galvani 116fd7f0d66SPaolo Bonzini const VMStateDescription vmstate_fifo8 = { 117fd7f0d66SPaolo Bonzini .name = "Fifo8", 118fd7f0d66SPaolo Bonzini .version_id = 1, 119fd7f0d66SPaolo Bonzini .minimum_version_id = 1, 120fd7f0d66SPaolo Bonzini .fields = (VMStateField[]) { 12159046ec2SHalil Pasic VMSTATE_VBUFFER_UINT32(data, Fifo8, 1, NULL, capacity), 122fd7f0d66SPaolo Bonzini VMSTATE_UINT32(head, Fifo8), 123fd7f0d66SPaolo Bonzini VMSTATE_UINT32(num, Fifo8), 124fd7f0d66SPaolo Bonzini VMSTATE_END_OF_LIST() 125fd7f0d66SPaolo Bonzini } 126fd7f0d66SPaolo Bonzini }; 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