From: =?utf-8?q?Kristian_H=C3=B8gsberg?= Subject: [PATCH 3/11] firewire: Implement proper transaction cancelation. Date: Tue, 6 Feb 2007 14:49:32 -0500 Drivers such as fw-sbp2 had no way to properly cancel in-progress transactions, which could leave a pending transaction or an unset packet in the low-level queues after kfree'ing the containing structure. fw_cancel_transaction() lets drivers cancel a submitted transaction. Signed-off-by: Kristian Høgsberg Signed-off-by: Stefan Richter --- drivers/firewire/fw-card.c | 7 +++++ drivers/firewire/fw-ohci.c | 33 ++++++++++++++++++++++ drivers/firewire/fw-sbp2.c | 3 ++ drivers/firewire/fw-transaction.c | 54 ++++++++++++++++++++++++++++++++----- drivers/firewire/fw-transaction.h | 5 +++ 5 files changed, 95 insertions(+), 7 deletions(-) diff --git a/drivers/firewire/fw-card.c b/drivers/firewire/fw-card.c index 7f5dc43..f785b10 100644 --- a/drivers/firewire/fw-card.c +++ b/drivers/firewire/fw-card.c @@ -475,6 +475,12 @@ dummy_send_response(struct fw_card *card, struct fw_packet *packet) } static int +dummy_cancel_packet(struct fw_card *card, struct fw_packet *packet) +{ + return -ENOENT; +} + +static int dummy_enable_phys_dma(struct fw_card *card, int node_id, int generation) { @@ -487,6 +493,7 @@ static struct fw_card_driver dummy_driver = { .update_phy_reg = dummy_update_phy_reg, .set_config_rom = dummy_set_config_rom, .send_request = dummy_send_request, + .cancel_packet = dummy_cancel_packet, .send_response = dummy_send_response, .enable_phys_dma = dummy_enable_phys_dma, }; diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c index 017d3d5..37291e6 100644 --- a/drivers/firewire/fw-ohci.c +++ b/drivers/firewire/fw-ohci.c @@ -79,6 +79,7 @@ struct at_context { struct fw_ohci *ohci; dma_addr_t descriptor_bus; dma_addr_t buffer_bus; + struct fw_packet *current_packet; struct list_head list; @@ -489,6 +490,7 @@ at_context_setup_packet(struct at_context *ctx, struct list_head *list) ctx->descriptor_bus | z); reg_write(ctx->ohci, control_set(ctx->regs), CONTEXT_RUN | CONTEXT_WAKE); + ctx->current_packet = packet; } else { /* We dont return error codes from this function; all * transmission errors are reported through the @@ -524,6 +526,12 @@ static void at_context_tasklet(unsigned long data) at_context_stop(ctx); + /* If the head of the list isn't the packet that just got + * transmitted, the packet got cancelled before we finished + * transmitting it. */ + if (ctx->current_packet != packet) + goto skip_to_next; + if (packet->payload_length > 0) { dma_unmap_single(ohci->card.device, packet->payload_bus, packet->payload_length, DMA_TO_DEVICE); @@ -564,6 +572,7 @@ static void at_context_tasklet(unsigned long data) } else complete_transmission(packet, evt - 16, &list); + skip_to_next: /* If more packets are queued, set up the next one. */ if (!list_empty(&ctx->list)) at_context_setup_packet(ctx, &list); @@ -1012,6 +1021,29 @@ static void ohci_send_response(struct fw_card *card, struct fw_packet *packet) at_context_transmit(&ohci->at_response_ctx, packet); } +static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet) +{ + struct fw_ohci *ohci = fw_ohci(card); + LIST_HEAD(list); + unsigned long flags; + + spin_lock_irqsave(&ohci->lock, flags); + + if (packet->ack == 0) { + fw_notify("cancelling packet %p (header[0]=%08x)\n", + packet, packet->header[0]); + + complete_transmission(packet, RCODE_CANCELLED, &list); + } + + spin_unlock_irqrestore(&ohci->lock, flags); + + do_packet_callbacks(ohci, &list); + + /* Return success if we actually cancelled something. */ + return list_empty(&list) ? -ENOENT : 0; +} + static int ohci_enable_phys_dma(struct fw_card *card, int node_id, int generation) { @@ -1339,6 +1371,7 @@ static const struct fw_card_driver ohci_driver = { .set_config_rom = ohci_set_config_rom, .send_request = ohci_send_request, .send_response = ohci_send_response, + .cancel_packet = ohci_cancel_packet, .enable_phys_dma = ohci_enable_phys_dma, .allocate_iso_context = ohci_allocate_iso_context, diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c index 54cad3a..bb13339 100644 --- a/drivers/firewire/fw-sbp2.c +++ b/drivers/firewire/fw-sbp2.c @@ -348,6 +348,9 @@ static void sbp2_cancel_orbs(struct fw_unit *unit) spin_unlock_irqrestore(&device->card->lock, flags); list_for_each_entry_safe(orb, next, &list, link) { + if (fw_cancel_transaction(device->card, &orb->t) == 0) + continue; + orb->rcode = RCODE_CANCELLED; orb->callback(orb, NULL); } diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c index fb3b77e..5394569 100644 --- a/drivers/firewire/fw-transaction.c +++ b/drivers/firewire/fw-transaction.c @@ -59,20 +59,52 @@ #define phy_config_root_id(node_id) ((((node_id) & 0x3f) << 24) | (1 << 23)) #define phy_identifier(id) ((id) << 30) -static void -close_transaction(struct fw_transaction *t, struct fw_card *card, int rcode, - u32 * payload, size_t length) +static int +close_transaction(struct fw_transaction *transaction, + struct fw_card *card, int rcode, + u32 *payload, size_t length) { + struct fw_transaction *t; unsigned long flags; spin_lock_irqsave(&card->lock, flags); - card->tlabel_mask &= ~(1 << t->tlabel); - list_del(&t->link); + list_for_each_entry(t, &card->transaction_list, link) { + if (t == transaction) { + list_del(&t->link); + card->tlabel_mask &= ~(1 << t->tlabel); + break; + } + } spin_unlock_irqrestore(&card->lock, flags); - t->callback(card, rcode, payload, length, t->callback_data); + if (&t->link != &card->transaction_list) { + t->callback(card, rcode, payload, length, t->callback_data); + return 0; + } + + return -ENOENT; } +/* Only valid for transactions that are potentially pending (ie have + * been sent). */ +int +fw_cancel_transaction(struct fw_card *card, + struct fw_transaction *transaction) +{ + /* 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. */ + + return close_transaction(transaction, card, RCODE_CANCELLED, NULL, 0); +} +EXPORT_SYMBOL(fw_cancel_transaction); + static void transmit_complete_callback(struct fw_packet *packet, struct fw_card *card, int status) @@ -162,6 +194,7 @@ fw_fill_request(struct fw_packet *packet, int tcode, int tlabel, packet->speed = speed; packet->generation = generation; + packet->ack = 0; } /** @@ -298,8 +331,14 @@ void fw_flush_transactions(struct fw_card *card) card->tlabel_mask = 0; spin_unlock_irqrestore(&card->lock, flags); - list_for_each_entry_safe(t, next, &list, link) + list_for_each_entry_safe(t, next, &list, link) { + card->driver->cancel_packet(card, &t->packet); + + /* At this point cancel_packet will never call the + * transaction callback, since we just took all the + * transactions out of the list. So do it here.*/ t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data); + } } static struct fw_address_handler * @@ -531,6 +570,7 @@ allocate_request(struct fw_packet *p) request->response.speed = p->speed; request->response.timestamp = t; request->response.generation = p->generation; + request->response.ack = 0; request->response.callback = free_response_callback; request->ack = p->ack; request->length = length; diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h index 50ec2c6..8f0283c 100644 --- a/drivers/firewire/fw-transaction.h +++ b/drivers/firewire/fw-transaction.h @@ -391,6 +391,8 @@ struct fw_card_driver { void (*send_request) (struct fw_card *card, struct fw_packet *packet); void (*send_response) (struct fw_card *card, struct fw_packet *packet); + /* Calling cancel is valid once a packet has been submitted. */ + int (*cancel_packet) (struct fw_card *card, struct fw_packet *packet); /* Allow the specified node ID to do direct DMA out and in of * host memory. The card will disable this for all node when @@ -421,6 +423,9 @@ fw_send_request(struct fw_card *card, struct fw_transaction *t, void *data, size_t length, fw_transaction_callback_t callback, void *callback_data); +int fw_cancel_transaction(struct fw_card *card, + struct fw_transaction *transaction); + void fw_flush_transactions(struct fw_card *card); void fw_send_phy_config(struct fw_card *card, -- 1.4.4.2