diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c index 7e9657e9c3..04c9a557b6 100644 --- a/hw/scsi/esp.c +++ b/hw/scsi/esp.c @@ -197,39 +197,9 @@ static uint8_t esp_fifo_pop(ESPState *s) return val; } -static uint32_t esp_fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest, int maxlen) -{ - const uint8_t *buf; - uint32_t n, n2; - int len; - - if (maxlen == 0) { - return 0; - } - - len = maxlen; - buf = fifo8_pop_bufptr(fifo, len, &n); - if (dest) { - memcpy(dest, buf, n); - } - - /* Add FIFO wraparound if needed */ - len -= n; - len = MIN(len, fifo8_num_used(fifo)); - if (len) { - buf = fifo8_pop_bufptr(fifo, len, &n2); - if (dest) { - memcpy(&dest[n], buf, n2); - } - n += n2; - } - - return n; -} - static uint32_t esp_fifo_pop_buf(ESPState *s, uint8_t *dest, int maxlen) { - uint32_t len = esp_fifo8_pop_buf(&s->fifo, dest, maxlen); + uint32_t len = fifo8_pop_buf(&s->fifo, dest, maxlen); esp_update_drq(s); return len; @@ -335,7 +305,7 @@ static void do_command_phase(ESPState *s) if (!cmdlen || !s->current_dev) { return; } - esp_fifo8_pop_buf(&s->cmdfifo, buf, cmdlen); + fifo8_pop_buf(&s->cmdfifo, buf, cmdlen); current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun); if (!current_lun) { @@ -381,7 +351,7 @@ static void do_message_phase(ESPState *s) /* Ignore extended messages for now */ if (s->cmdfifo_cdb_offset) { int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo)); - esp_fifo8_pop_buf(&s->cmdfifo, NULL, len); + fifo8_pop_buf(&s->cmdfifo, NULL, len); s->cmdfifo_cdb_offset = 0; } } diff --git a/include/qemu/fifo8.h b/include/qemu/fifo8.h index a30220c8e9..bca6da306f 100644 --- a/include/qemu/fifo8.h +++ b/include/qemu/fifo8.h @@ -62,12 +62,28 @@ void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num); */ uint8_t fifo8_pop(Fifo8 *fifo); +/** + * fifo8_pop_buf: + * @fifo: FIFO to pop from + * @dest: the buffer to write the data into (can be NULL) + * @destlen: size of @dest and maximum number of bytes to pop + * + * Pop a number of elements from the FIFO up to a maximum of @destlen. + * The popped data is copied into the @dest buffer. + * Care is taken when the data wraps around in the ring buffer. + * + * Returns: number of bytes popped. + */ +uint32_t fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen); + /** * fifo8_pop_bufptr: * @fifo: FIFO to pop from * @max: maximum number of bytes to pop * @numptr: pointer filled with number of bytes returned (can be NULL) * + * New code should prefer to use fifo8_pop_buf() instead of fifo8_pop_bufptr(). + * * Pop a number of elements from the FIFO up to a maximum of @max. The buffer * containing the popped data is returned. This buffer points directly into * the internal FIFO backing store and data (without checking for overflow!) diff --git a/util/fifo8.c b/util/fifo8.c index 5bbb6150b6..a250ea9f80 100644 --- a/util/fifo8.c +++ b/util/fifo8.c @@ -102,6 +102,35 @@ const uint8_t *fifo8_pop_bufptr(Fifo8 *fifo, uint32_t max, uint32_t *numptr) return fifo8_peekpop_buf(fifo, max, numptr, true); } +uint32_t fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen) +{ + const uint8_t *buf; + uint32_t n1, n2 = 0; + uint32_t len; + + if (destlen == 0) { + return 0; + } + + len = destlen; + buf = fifo8_pop_bufptr(fifo, len, &n1); + if (dest) { + memcpy(dest, buf, n1); + } + + /* Add FIFO wraparound if needed */ + len -= n1; + len = MIN(len, fifo8_num_used(fifo)); + if (len) { + buf = fifo8_pop_bufptr(fifo, len, &n2); + if (dest) { + memcpy(&dest[n1], buf, n2); + } + } + + return n1 + n2; +} + bool fifo8_is_empty(Fifo8 *fifo) { return (fifo->num == 0);