From ff9ef5787046c3fd20cf9f7ca1cd70260c1eedb9 Mon Sep 17 00:00:00 2001 From: Johan Hedberg Date: Wed, 4 Jan 2012 14:23:45 +0200 Subject: [PATCH] Bluetooth: Add discovery state tracking This patch adds proper state tracking to the device discovery process. This makes it possible to return appropriate errors when trying to stop a non-active discovery or start discovery when it is already ongoing. Once name resolving is implemented this also makes it possible to know what the right action to do is when a remote name lookup is cancelled. Signed-off-by: Johan Hedberg Acked-by: Marcel Holtmann --- include/net/bluetooth/hci_core.h | 9 +++++++++ net/bluetooth/hci_core.c | 25 +++++++++++++++++++++++++ net/bluetooth/hci_event.c | 6 +++--- net/bluetooth/mgmt.c | 16 ++++++++++++++++ 4 files changed, 53 insertions(+), 3 deletions(-) diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index 5a566fd5e2a6..2f19de4770b6 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -57,6 +57,12 @@ struct inquiry_entry { }; struct discovery_state { + enum { + DISCOVERY_STOPPED, + DISCOVERY_STARTING, + DISCOVERY_ACTIVE, + DISCOVERY_STOPPING, + } state; struct list_head all; /* All devices found during inquiry */ struct list_head unknown; /* Name state not known */ struct list_head resolve; /* Name needs to be resolved */ @@ -359,11 +365,14 @@ extern int sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb); static inline void discovery_init(struct hci_dev *hdev) { + hdev->discovery.state = DISCOVERY_STOPPED; INIT_LIST_HEAD(&hdev->discovery.all); INIT_LIST_HEAD(&hdev->discovery.unknown); INIT_LIST_HEAD(&hdev->discovery.resolve); } +void hci_discovery_set_state(struct hci_dev *hdev, int state); + static inline int inquiry_cache_empty(struct hci_dev *hdev) { return list_empty(&hdev->discovery.all); diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 55509b0a810a..b68719230601 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -355,6 +355,30 @@ struct hci_dev *hci_dev_get(int index) } /* ---- Inquiry support ---- */ + +void hci_discovery_set_state(struct hci_dev *hdev, int state) +{ + BT_DBG("%s state %u -> %u", hdev->name, hdev->discovery.state, state); + + if (hdev->discovery.state == state) + return; + + switch (state) { + case DISCOVERY_STOPPED: + mgmt_discovering(hdev, 0); + break; + case DISCOVERY_STARTING: + break; + case DISCOVERY_ACTIVE: + mgmt_discovering(hdev, 1); + break; + case DISCOVERY_STOPPING: + break; + } + + hdev->discovery.state = state; +} + static void inquiry_cache_flush(struct hci_dev *hdev) { struct discovery_state *cache = &hdev->discovery; @@ -367,6 +391,7 @@ static void inquiry_cache_flush(struct hci_dev *hdev) INIT_LIST_HEAD(&cache->unknown); INIT_LIST_HEAD(&cache->resolve); + cache->state = DISCOVERY_STOPPED; } struct inquiry_entry *hci_inquiry_cache_lookup(struct hci_dev *hdev, bdaddr_t *bdaddr) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index d4d20df9fbbf..43d69569a0d5 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -65,7 +65,7 @@ static void hci_cc_inquiry_cancel(struct hci_dev *hdev, struct sk_buff *skb) clear_bit(HCI_INQUIRY, &hdev->flags); hci_dev_lock(hdev); - mgmt_discovering(hdev, 0); + hci_discovery_set_state(hdev, DISCOVERY_STOPPED); hci_dev_unlock(hdev); hci_req_complete(hdev, HCI_OP_INQUIRY_CANCEL, status); @@ -1119,7 +1119,7 @@ static inline void hci_cs_inquiry(struct hci_dev *hdev, __u8 status) set_bit(HCI_INQUIRY, &hdev->flags); hci_dev_lock(hdev); - mgmt_discovering(hdev, 1); + hci_discovery_set_state(hdev, DISCOVERY_ACTIVE); hci_dev_unlock(hdev); } @@ -1507,7 +1507,7 @@ static inline void hci_inquiry_complete_evt(struct hci_dev *hdev, struct sk_buff return; hci_dev_lock(hdev); - mgmt_discovering(hdev, 0); + hci_discovery_set_state(hdev, DISCOVERY_STOPPED); hci_dev_unlock(hdev); } diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 894f11bc571d..590966ddfa63 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -1918,6 +1918,12 @@ static int start_discovery(struct sock *sk, u16 index, goto failed; } + if (hdev->discovery.state != DISCOVERY_STOPPED) { + err = cmd_status(sk, index, MGMT_OP_START_DISCOVERY, + MGMT_STATUS_BUSY); + goto failed; + } + cmd = mgmt_pending_add(sk, MGMT_OP_START_DISCOVERY, hdev, NULL, 0); if (!cmd) { err = -ENOMEM; @@ -1927,6 +1933,8 @@ static int start_discovery(struct sock *sk, u16 index, err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR); if (err < 0) mgmt_pending_remove(cmd); + else + hci_discovery_set_state(hdev, DISCOVERY_STARTING); failed: hci_dev_unlock(hdev); @@ -1950,6 +1958,12 @@ static int stop_discovery(struct sock *sk, u16 index) hci_dev_lock(hdev); + if (hdev->discovery.state != DISCOVERY_ACTIVE) { + err = cmd_status(sk, index, MGMT_OP_STOP_DISCOVERY, + MGMT_STATUS_REJECTED); + goto failed; + } + cmd = mgmt_pending_add(sk, MGMT_OP_STOP_DISCOVERY, hdev, NULL, 0); if (!cmd) { err = -ENOMEM; @@ -1959,6 +1973,8 @@ static int stop_discovery(struct sock *sk, u16 index) err = hci_cancel_inquiry(hdev); if (err < 0) mgmt_pending_remove(cmd); + else + hci_discovery_set_state(hdev, DISCOVERY_STOPPING); failed: hci_dev_unlock(hdev);