// SPDX-License-Identifier: GPL-2.0-or-later/* * Core IEEE1394 transaction logic * * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net> */ #include <linux/bug.h>#include <linux/completion.h>#include <linux/device.h>#include <linux/errno.h>#include <linux/firewire.h>#include <linux/firewire-constants.h>#include <linux/fs.h>#include <linux/init.h>#include <linux/jiffies.h>#include <linux/kernel.h>#include <linux/list.h>#include <linux/module.h>#include <linux/rculist.h>#include <linux/slab.h>#include <linux/spinlock.h>#include <linux/string.h>#include <linux/timer.h>#include <linux/types.h>#include <linux/workqueue.h> #include <asm/byteorder.h> #include "core.h"#include "packet-header-definitions.h"#include "phy-packet-definitions.h"#include <trace/events/firewire.h> #define HEADER_DESTINATION_IS_BROADCAST(header) \ ((async_header_get_destination(header) & 0x3f) == 0x3f) /* returns 0 if the split timeout handler is already running */static int try_cancel_split_timeout(struct fw_transaction *t){ if (t->is_split_transaction) return timer_delete(&t->split_timeout_timer); else return 1;} // card->transactions.lock must be acquired in advance.static void remove_transaction_entry(struct fw_card *card, struct fw_transaction *entry){ list_del_init(&entry->link); card->transactions.tlabel_mask &= ~(1ULL << entry->tlabel);} // Must be called without holding card->transactions.lock.void fw_cancel_pending_transactions(struct fw_card *card){ struct fw_transaction *t, *tmp; LIST_HEAD(pending_list); // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) { list_for_each_entry_safe(t, tmp, &card->transactions.list, link) { if (try_cancel_split_timeout(t)) list_move(&t->link, &pending_list); } } list_for_each_entry_safe(t, tmp, &pending_list, link) { list_del(&t->link); if (!t->with_tstamp) { t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp, 0, NULL, 0, t->callback_data); } }} // card->transactions.lock must be acquired in advance.#define find_and_pop_transaction_entry(card, condition) \({ \ struct fw_transaction *iter, *t = NULL; \ list_for_each_entry(iter, &card->transactions.list, link) { \ if (condition) { \ t = iter; \ break; \ } \ } \ if (t && try_cancel_split_timeout(t)) \ remove_transaction_entry(card, t); \ t; \}) static int close_transaction(struct fw_transaction *transaction, struct fw_card *card, int rcode, u32 response_tstamp){ struct fw_transaction *t; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) { t = find_and_pop_transaction_entry(card, iter == transaction); if (!t) return -ENOENT; } if (!t->with_tstamp) { t->callback.without_tstamp(card, rcode, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, rcode, t->packet.timestamp, response_tstamp, NULL, 0, t->callback_data); } return 0;} /* * Only valid for transactions that are potentially pending (ie have * been sent). */int fw_cancel_transaction(struct fw_card *card, struct fw_transaction *transaction){ u32 tstamp; /* * Cancel the packet transmission if it's still queued. That * will call the packet transmission callback which cancels * the transaction. */ if (card->driver->cancel_packet(card, &transaction->packet) == 0) return 0; /* * If the request packet has already been sent, we need to see * if the transaction is still pending and remove it in that case. */ if (transaction->packet.ack == 0) { // The timestamp is reused since it was just read now. tstamp = transaction->packet.timestamp; } else { u32 curr_cycle_time = 0; (void)fw_card_read_cycle_time(card, &curr_cycle_time); tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time); } return close_transaction(transaction, card, RCODE_CANCELLED, tstamp);}EXPORT_SYMBOL(fw_cancel_transaction); static void split_transaction_timeout_callback(struct timer_list *timer){ struct fw_transaction *t = timer_container_of(t, timer, split_timeout_timer); struct fw_card *card = t->card; scoped_guard(spinlock_irqsave, &card->transactions.lock) { if (list_empty(&t->link)) return; remove_transaction_entry(card, t); } if (!t->with_tstamp) { t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp, t->split_timeout_cycle, NULL, 0, t->callback_data); }} // card->transactions.lock should be acquired in advance for the linked list.static void start_split_transaction_timeout(struct fw_transaction *t, unsigned int delta){ if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) return; t->is_split_transaction = true; mod_timer(&t->split_timeout_timer, jiffies + delta);} static u32 compute_split_timeout_timestamp(struct fw_card *card, u32 request_timestamp); static void transmit_complete_callback(struct fw_packet *packet, struct fw_card *card, int status){ struct fw_transaction *t = container_of(packet, struct fw_transaction, packet); trace_async_request_outbound_complete((uintptr_t)t, card->index, packet->generation, packet->speed, status, packet->timestamp); switch (status) { case ACK_COMPLETE: close_transaction(t, card, RCODE_COMPLETE, packet->timestamp); break; case ACK_PENDING: { unsigned int delta; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->split_timeout.lock) { t->split_timeout_cycle = compute_split_timeout_timestamp(card, packet->timestamp) & 0xffff; delta = card->split_timeout.jiffies; } // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) start_split_transaction_timeout(t, delta); break; } case ACK_BUSY_X: case ACK_BUSY_A: case ACK_BUSY_B: close_transaction(t, card, RCODE_BUSY, packet->timestamp); break; case ACK_DATA_ERROR: close_transaction(t, card, RCODE_DATA_ERROR, packet->timestamp); break; case ACK_TYPE_ERROR: close_transaction(t, card, RCODE_TYPE_ERROR, packet->timestamp); break; default: /* * In this case the ack is really a juju specific * rcode, so just forward that to the callback. */ close_transaction(t, card, status, packet->timestamp); break; }} static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel, int destination_id, int source_id, int generation, int speed, unsigned long long offset, void *payload, size_t length){ int ext_tcode; if (tcode == TCODE_STREAM_DATA) { // The value of destination_id argument should include tag, channel, and sy fields // as isochronous packet header has. packet->header[0] = destination_id; isoc_header_set_data_length(packet->header, length); isoc_header_set_tcode(packet->header, TCODE_STREAM_DATA); packet->header_length = 4; packet->payload = payload; packet->payload_length = length; goto common; } if (tcode > 0x10) { ext_tcode = tcode & ~0x10; tcode = TCODE_LOCK_REQUEST; } else ext_tcode = 0; async_header_set_retry(packet->header, RETRY_X); async_header_set_tlabel(packet->header, tlabel); async_header_set_tcode(packet->header, tcode); async_header_set_destination(packet->header, destination_id); async_header_set_source(packet->header, source_id); async_header_set_offset(packet->header, offset); switch (tcode) { case TCODE_WRITE_QUADLET_REQUEST: async_header_set_quadlet_data(packet->header, *(u32 *)payload); packet->header_length = 16; packet->payload_length = 0; break; case TCODE_LOCK_REQUEST: case TCODE_WRITE_BLOCK_REQUEST: async_header_set_data_length(packet->header, length); async_header_set_extended_tcode(packet->header, ext_tcode); packet->header_length = 16; packet->payload = payload; packet->payload_length = length; break; case TCODE_READ_QUADLET_REQUEST: packet->header_length = 12; packet->payload_length = 0; break; case TCODE_READ_BLOCK_REQUEST: async_header_set_data_length(packet->header, length); async_header_set_extended_tcode(packet->header, ext_tcode); packet->header_length = 16; packet->payload_length = 0; break; default: WARN(1, "wrong tcode %d\n", tcode); } common: packet->speed = speed; packet->generation = generation; packet->ack = 0; packet->payload_mapped = false;} static int allocate_tlabel(struct fw_card *card)__must_hold(&card->transactions.lock){ int tlabel; lockdep_assert_held(&card->transactions.lock); tlabel = card->transactions.current_tlabel; while (card->transactions.tlabel_mask & (1ULL << tlabel)) { tlabel = (tlabel + 1) & 0x3f; if (tlabel == card->transactions.current_tlabel) return -EBUSY; } card->transactions.current_tlabel = (tlabel + 1) & 0x3f; card->transactions.tlabel_mask |= 1ULL << tlabel; return tlabel;} /** * __fw_send_request() - submit a request packet for transmission to generate callback for response * subaction with or without time stamp. * @card: interface to send the request at * @t: transaction instance to which the request belongs * @tcode: transaction code * @destination_id: destination node ID, consisting of bus_ID and phy_ID * @generation: bus generation in which request and response are valid * @speed: transmission speed * @offset: 48bit wide offset into destination's address space * @payload: data payload for the request subaction * @length: length of the payload, in bytes * @callback: union of two functions whether to receive time stamp or not for response * subaction. * @with_tstamp: Whether to receive time stamp or not for response subaction. * @callback_data: data to be passed to the transaction completion callback * * Submit a request packet into the asynchronous request transmission queue. * Can be called from atomic context. If you prefer a blocking API, use * fw_run_transaction() in a context that can sleep. * * In case of lock requests, specify one of the firewire-core specific %TCODE_ * constants instead of %TCODE_LOCK_REQUEST in @tcode. * * Make sure that the value in @destination_id is not older than the one in * @generation. Otherwise the request is in danger to be sent to a wrong node. * * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller * needs to synthesize @destination_id with fw_stream_packet_destination_id(). * It will contain tag, channel, and sy data instead of a node ID then. * * The payload buffer at @data is going to be DMA-mapped except in case of * @length <= 8 or of local (loopback) requests. Hence make sure that the * buffer complies with the restrictions of the streaming DMA mapping API. * @payload must not be freed before the @callback is called. * * In case of request types without payload, @data is NULL and @length is 0. * * After the transaction is completed successfully or unsuccessfully, the * @callback will be called. Among its parameters is the response code which * is either one of the rcodes per IEEE 1394 or, in case of internal errors, * the firewire-core specific %RCODE_SEND_ERROR. The other firewire-core * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION, * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request * generation, or missing ACK respectively. * * Note some timing corner cases: fw_send_request() may complete much earlier * than when the request packet actually hits the wire. On the other hand, * transaction completion and hence execution of @callback may happen even * before fw_send_request() returns. */void __fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode, int destination_id, int generation, int speed, unsigned long long offset, void *payload, size_t length, union fw_transaction_callback callback, bool with_tstamp, void *callback_data){ int tlabel; /* * Allocate tlabel from the bitmap and put the transaction on * the list while holding the card spinlock. */ // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) tlabel = allocate_tlabel(card); if (tlabel < 0) { if (!with_tstamp) { callback.without_tstamp(card, RCODE_SEND_ERROR, NULL, 0, callback_data); } else { // Timestamping on behalf of hardware. u32 curr_cycle_time = 0; u32 tstamp; (void)fw_card_read_cycle_time(card, &curr_cycle_time); tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time); callback.with_tstamp(card, RCODE_SEND_ERROR, tstamp, tstamp, NULL, 0, callback_data); } return; } t->node_id = destination_id; t->tlabel = tlabel; t->card = card; t->is_split_transaction = false; timer_setup(&t->split_timeout_timer, split_transaction_timeout_callback, 0); t->callback = callback; t->with_tstamp = with_tstamp; t->callback_data = callback_data; t->packet.callback = transmit_complete_callback; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->lock) { // The node_id field of fw_card can be updated when handling SelfIDComplete. fw_fill_request(&t->packet, tcode, t->tlabel, destination_id, card->node_id, generation, speed, offset, payload, length); } // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) list_add_tail(&t->link, &card->transactions.list); // Safe with no lock, since the index field of fw_card is immutable once assigned. trace_async_request_outbound_initiate((uintptr_t)t, card->index, generation, speed, t->packet.header, payload, tcode_is_read_request(tcode) ? 0 : length / 4); card->driver->send_request(card, &t->packet);}EXPORT_SYMBOL_GPL(__fw_send_request); struct transaction_callback_data { struct completion done; void *payload; int rcode;}; static void transaction_callback(struct fw_card *card, int rcode, void *payload, size_t length, void *data){ struct transaction_callback_data *d = data; if (rcode == RCODE_COMPLETE) memcpy(d->payload, payload, length); d->rcode = rcode; complete(&d->done);} /** * fw_run_transaction() - send request and sleep until transaction is completed * @card: card interface for this request * @tcode: transaction code * @destination_id: destination node ID, consisting of bus_ID and phy_ID * @generation: bus generation in which request and response are valid * @speed: transmission speed * @offset: 48bit wide offset into destination's address space * @payload: data payload for the request subaction * @length: length of the payload, in bytes * * Returns the RCODE. See fw_send_request() for parameter documentation. * Unlike fw_send_request(), @data points to the payload of the request or/and * to the payload of the response. DMA mapping restrictions apply to outbound * request payloads of >= 8 bytes but not to inbound response payloads. */int fw_run_transaction(struct fw_card *card, int tcode, int destination_id, int generation, int speed, unsigned long long offset, void *payload, size_t length){ struct transaction_callback_data d; struct fw_transaction t; timer_setup_on_stack(&t.split_timeout_timer, NULL, 0); init_completion(&d.done); d.payload = payload; fw_send_request(card, &t, tcode, destination_id, generation, speed, offset, payload, length, transaction_callback, &d); wait_for_completion(&d.done); timer_destroy_on_stack(&t.split_timeout_timer); return d.rcode;}EXPORT_SYMBOL(fw_run_transaction); static DEFINE_MUTEX(phy_config_mutex);static DECLARE_COMPLETION(phy_config_done);Lines 1–500 of 1508. Load more
// SPDX-License-Identifier: GPL-2.0-or-later /* * Core IEEE1394 transaction logic * * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net> */ #include <linux/bug.h> #include <linux/completion.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/firewire.h> #include <linux/firewire-constants.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/jiffies.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> #include <linux/rculist.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/timer.h> #include <linux/types.h> #include <linux/workqueue.h> #include <asm/byteorder.h> #include "core.h" #include "packet-header-definitions.h" #include "phy-packet-definitions.h" #include <trace/events/firewire.h> #define HEADER_DESTINATION_IS_BROADCAST(header) \ ((async_header_get_destination(header) & 0x3f) == 0x3f) /* returns 0 if the split timeout handler is already running */ static int try_cancel_split_timeout(struct fw_transaction *t) { if (t->is_split_transaction) return timer_delete(&t->split_timeout_timer); else return 1; } // card->transactions.lock must be acquired in advance. static void remove_transaction_entry(struct fw_card *card, struct fw_transaction *entry) { list_del_init(&entry->link); card->transactions.tlabel_mask &= ~(1ULL << entry->tlabel); } // Must be called without holding card->transactions.lock. void fw_cancel_pending_transactions(struct fw_card *card) { struct fw_transaction *t, *tmp; LIST_HEAD(pending_list); // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) { list_for_each_entry_safe(t, tmp, &card->transactions.list, link) { if (try_cancel_split_timeout(t)) list_move(&t->link, &pending_list); } } list_for_each_entry_safe(t, tmp, &pending_list, link) { list_del(&t->link); if (!t->with_tstamp) { t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp, 0, NULL, 0, t->callback_data); } } } // card->transactions.lock must be acquired in advance. #define find_and_pop_transaction_entry(card, condition) \ ({ \ struct fw_transaction *iter, *t = NULL; \ list_for_each_entry(iter, &card->transactions.list, link) { \ if (condition) { \ t = iter; \ break; \ } \ } \ if (t && try_cancel_split_timeout(t)) \ remove_transaction_entry(card, t); \ t; \ }) static int close_transaction(struct fw_transaction *transaction, struct fw_card *card, int rcode, u32 response_tstamp) { struct fw_transaction *t; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) { t = find_and_pop_transaction_entry(card, iter == transaction); if (!t) return -ENOENT; } if (!t->with_tstamp) { t->callback.without_tstamp(card, rcode, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, rcode, t->packet.timestamp, response_tstamp, NULL, 0, t->callback_data); } return 0; } /* * Only valid for transactions that are potentially pending (ie have * been sent). */ int fw_cancel_transaction(struct fw_card *card, struct fw_transaction *transaction) { u32 tstamp; /* * Cancel the packet transmission if it's still queued. That * will call the packet transmission callback which cancels * the transaction. */ if (card->driver->cancel_packet(card, &transaction->packet) == 0) return 0; /* * If the request packet has already been sent, we need to see * if the transaction is still pending and remove it in that case. */ if (transaction->packet.ack == 0) { // The timestamp is reused since it was just read now. tstamp = transaction->packet.timestamp; } else { u32 curr_cycle_time = 0; (void)fw_card_read_cycle_time(card, &curr_cycle_time); tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time); } return close_transaction(transaction, card, RCODE_CANCELLED, tstamp); } EXPORT_SYMBOL(fw_cancel_transaction); static void split_transaction_timeout_callback(struct timer_list *timer) { struct fw_transaction *t = timer_container_of(t, timer, split_timeout_timer); struct fw_card *card = t->card; scoped_guard(spinlock_irqsave, &card->transactions.lock) { if (list_empty(&t->link)) return; remove_transaction_entry(card, t); } if (!t->with_tstamp) { t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data); } else { t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp, t->split_timeout_cycle, NULL, 0, t->callback_data); } } // card->transactions.lock should be acquired in advance for the linked list. static void start_split_transaction_timeout(struct fw_transaction *t, unsigned int delta) { if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) return; t->is_split_transaction = true; mod_timer(&t->split_timeout_timer, jiffies + delta); } static u32 compute_split_timeout_timestamp(struct fw_card *card, u32 request_timestamp); static void transmit_complete_callback(struct fw_packet *packet, struct fw_card *card, int status) { struct fw_transaction *t = container_of(packet, struct fw_transaction, packet); trace_async_request_outbound_complete((uintptr_t)t, card->index, packet->generation, packet->speed, status, packet->timestamp); switch (status) { case ACK_COMPLETE: close_transaction(t, card, RCODE_COMPLETE, packet->timestamp); break; case ACK_PENDING: { unsigned int delta; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->split_timeout.lock) { t->split_timeout_cycle = compute_split_timeout_timestamp(card, packet->timestamp) & 0xffff; delta = card->split_timeout.jiffies; } // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) start_split_transaction_timeout(t, delta); break; } case ACK_BUSY_X: case ACK_BUSY_A: case ACK_BUSY_B: close_transaction(t, card, RCODE_BUSY, packet->timestamp); break; case ACK_DATA_ERROR: close_transaction(t, card, RCODE_DATA_ERROR, packet->timestamp); break; case ACK_TYPE_ERROR: close_transaction(t, card, RCODE_TYPE_ERROR, packet->timestamp); break; default: /* * In this case the ack is really a juju specific * rcode, so just forward that to the callback. */ close_transaction(t, card, status, packet->timestamp); break; } } static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel, int destination_id, int source_id, int generation, int speed, unsigned long long offset, void *payload, size_t length) { int ext_tcode; if (tcode == TCODE_STREAM_DATA) { // The value of destination_id argument should include tag, channel, and sy fields // as isochronous packet header has. packet->header[0] = destination_id; isoc_header_set_data_length(packet->header, length); isoc_header_set_tcode(packet->header, TCODE_STREAM_DATA); packet->header_length = 4; packet->payload = payload; packet->payload_length = length; goto common; } if (tcode > 0x10) { ext_tcode = tcode & ~0x10; tcode = TCODE_LOCK_REQUEST; } else ext_tcode = 0; async_header_set_retry(packet->header, RETRY_X); async_header_set_tlabel(packet->header, tlabel); async_header_set_tcode(packet->header, tcode); async_header_set_destination(packet->header, destination_id); async_header_set_source(packet->header, source_id); async_header_set_offset(packet->header, offset); switch (tcode) { case TCODE_WRITE_QUADLET_REQUEST: async_header_set_quadlet_data(packet->header, *(u32 *)payload); packet->header_length = 16; packet->payload_length = 0; break; case TCODE_LOCK_REQUEST: case TCODE_WRITE_BLOCK_REQUEST: async_header_set_data_length(packet->header, length); async_header_set_extended_tcode(packet->header, ext_tcode); packet->header_length = 16; packet->payload = payload; packet->payload_length = length; break; case TCODE_READ_QUADLET_REQUEST: packet->header_length = 12; packet->payload_length = 0; break; case TCODE_READ_BLOCK_REQUEST: async_header_set_data_length(packet->header, length); async_header_set_extended_tcode(packet->header, ext_tcode); packet->header_length = 16; packet->payload_length = 0; break; default: WARN(1, "wrong tcode %d\n", tcode); } common: packet->speed = speed; packet->generation = generation; packet->ack = 0; packet->payload_mapped = false; } static int allocate_tlabel(struct fw_card *card) __must_hold(&card->transactions.lock) { int tlabel; lockdep_assert_held(&card->transactions.lock); tlabel = card->transactions.current_tlabel; while (card->transactions.tlabel_mask & (1ULL << tlabel)) { tlabel = (tlabel + 1) & 0x3f; if (tlabel == card->transactions.current_tlabel) return -EBUSY; } card->transactions.current_tlabel = (tlabel + 1) & 0x3f; card->transactions.tlabel_mask |= 1ULL << tlabel; return tlabel; } /** * __fw_send_request() - submit a request packet for transmission to generate callback for response * subaction with or without time stamp. * @card: interface to send the request at * @t: transaction instance to which the request belongs * @tcode: transaction code * @destination_id: destination node ID, consisting of bus_ID and phy_ID * @generation: bus generation in which request and response are valid * @speed: transmission speed * @offset: 48bit wide offset into destination's address space * @payload: data payload for the request subaction * @length: length of the payload, in bytes * @callback: union of two functions whether to receive time stamp or not for response * subaction. * @with_tstamp: Whether to receive time stamp or not for response subaction. * @callback_data: data to be passed to the transaction completion callback * * Submit a request packet into the asynchronous request transmission queue. * Can be called from atomic context. If you prefer a blocking API, use * fw_run_transaction() in a context that can sleep. * * In case of lock requests, specify one of the firewire-core specific %TCODE_ * constants instead of %TCODE_LOCK_REQUEST in @tcode. * * Make sure that the value in @destination_id is not older than the one in * @generation. Otherwise the request is in danger to be sent to a wrong node. * * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller * needs to synthesize @destination_id with fw_stream_packet_destination_id(). * It will contain tag, channel, and sy data instead of a node ID then. * * The payload buffer at @data is going to be DMA-mapped except in case of * @length <= 8 or of local (loopback) requests. Hence make sure that the * buffer complies with the restrictions of the streaming DMA mapping API. * @payload must not be freed before the @callback is called. * * In case of request types without payload, @data is NULL and @length is 0. * * After the transaction is completed successfully or unsuccessfully, the * @callback will be called. Among its parameters is the response code which * is either one of the rcodes per IEEE 1394 or, in case of internal errors, * the firewire-core specific %RCODE_SEND_ERROR. The other firewire-core * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION, * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request * generation, or missing ACK respectively. * * Note some timing corner cases: fw_send_request() may complete much earlier * than when the request packet actually hits the wire. On the other hand, * transaction completion and hence execution of @callback may happen even * before fw_send_request() returns. */ void __fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode, int destination_id, int generation, int speed, unsigned long long offset, void *payload, size_t length, union fw_transaction_callback callback, bool with_tstamp, void *callback_data) { int tlabel; /* * Allocate tlabel from the bitmap and put the transaction on * the list while holding the card spinlock. */ // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) tlabel = allocate_tlabel(card); if (tlabel < 0) { if (!with_tstamp) { callback.without_tstamp(card, RCODE_SEND_ERROR, NULL, 0, callback_data); } else { // Timestamping on behalf of hardware. u32 curr_cycle_time = 0; u32 tstamp; (void)fw_card_read_cycle_time(card, &curr_cycle_time); tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time); callback.with_tstamp(card, RCODE_SEND_ERROR, tstamp, tstamp, NULL, 0, callback_data); } return; } t->node_id = destination_id; t->tlabel = tlabel; t->card = card; t->is_split_transaction = false; timer_setup(&t->split_timeout_timer, split_transaction_timeout_callback, 0); t->callback = callback; t->with_tstamp = with_tstamp; t->callback_data = callback_data; t->packet.callback = transmit_complete_callback; // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->lock) { // The node_id field of fw_card can be updated when handling SelfIDComplete. fw_fill_request(&t->packet, tcode, t->tlabel, destination_id, card->node_id, generation, speed, offset, payload, length); } // NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for // local destination never runs in any type of IRQ context. scoped_guard(spinlock_irqsave, &card->transactions.lock) list_add_tail(&t->link, &card->transactions.list); // Safe with no lock, since the index field of fw_card is immutable once assigned. trace_async_request_outbound_initiate((uintptr_t)t, card->index, generation, speed, t->packet.header, payload, tcode_is_read_request(tcode) ? 0 : length / 4); card->driver->send_request(card, &t->packet); } EXPORT_SYMBOL_GPL(__fw_send_request); struct transaction_callback_data { struct completion done; void *payload; int rcode; }; static void transaction_callback(struct fw_card *card, int rcode, void *payload, size_t length, void *data) { struct transaction_callback_data *d = data; if (rcode == RCODE_COMPLETE) memcpy(d->payload, payload, length); d->rcode = rcode; complete(&d->done); } /** * fw_run_transaction() - send request and sleep until transaction is completed * @card: card interface for this request * @tcode: transaction code * @destination_id: destination node ID, consisting of bus_ID and phy_ID * @generation: bus generation in which request and response are valid * @speed: transmission speed * @offset: 48bit wide offset into destination's address space * @payload: data payload for the request subaction * @length: length of the payload, in bytes * * Returns the RCODE. See fw_send_request() for parameter documentation. * Unlike fw_send_request(), @data points to the payload of the request or/and * to the payload of the response. DMA mapping restrictions apply to outbound * request payloads of >= 8 bytes but not to inbound response payloads. */ int fw_run_transaction(struct fw_card *card, int tcode, int destination_id, int generation, int speed, unsigned long long offset, void *payload, size_t length) { struct transaction_callback_data d; struct fw_transaction t; timer_setup_on_stack(&t.split_timeout_timer, NULL, 0); init_completion(&d.done); d.payload = payload; fw_send_request(card, &t, tcode, destination_id, generation, speed, offset, payload, length, transaction_callback, &d); wait_for_completion(&d.done); timer_destroy_on_stack(&t.split_timeout_timer); return d.rcode; } EXPORT_SYMBOL(fw_run_transaction); static DEFINE_MUTEX(phy_config_mutex); static DECLARE_COMPLETION(phy_config_done);