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Diffstat (limited to 'net/nfc/core.c')
-rw-r--r--net/nfc/core.c112
1 files changed, 85 insertions, 27 deletions
diff --git a/net/nfc/core.c b/net/nfc/core.c
index 3192c3f589ee..9f6ce011d35d 100644
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -97,7 +97,7 @@ int nfc_dev_down(struct nfc_dev *dev)
goto error;
}
- if (dev->polling || dev->activated_target_idx != NFC_TARGET_IDX_NONE) {
+ if (dev->polling || dev->active_target) {
rc = -EBUSY;
goto error;
}
@@ -183,11 +183,27 @@ error:
return rc;
}
+static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx)
+{
+ int i;
+
+ if (dev->n_targets == 0)
+ return NULL;
+
+ for (i = 0; i < dev->n_targets ; i++) {
+ if (dev->targets[i].idx == target_idx)
+ return &dev->targets[i];
+ }
+
+ return NULL;
+}
+
int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
{
int rc = 0;
u8 *gb;
size_t gb_len;
+ struct nfc_target *target;
pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
@@ -212,9 +228,15 @@ int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
goto error;
}
- rc = dev->ops->dep_link_up(dev, target_index, comm_mode, gb, gb_len);
+ target = nfc_find_target(dev, target_index);
+ if (target == NULL) {
+ rc = -ENOTCONN;
+ goto error;
+ }
+
+ rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len);
if (!rc)
- dev->activated_target_idx = target_index;
+ dev->active_target = target;
error:
device_unlock(&dev->dev);
@@ -250,7 +272,7 @@ int nfc_dep_link_down(struct nfc_dev *dev)
rc = dev->ops->dep_link_down(dev);
if (!rc) {
dev->dep_link_up = false;
- dev->activated_target_idx = NFC_TARGET_IDX_NONE;
+ dev->active_target = NULL;
nfc_llcp_mac_is_down(dev);
nfc_genl_dep_link_down_event(dev);
}
@@ -282,6 +304,7 @@ EXPORT_SYMBOL(nfc_dep_link_is_up);
int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
{
int rc;
+ struct nfc_target *target;
pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
dev_name(&dev->dev), target_idx, protocol);
@@ -293,9 +316,20 @@ int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
goto error;
}
- rc = dev->ops->activate_target(dev, target_idx, protocol);
+ if (dev->active_target) {
+ rc = -EBUSY;
+ goto error;
+ }
+
+ target = nfc_find_target(dev, target_idx);
+ if (target == NULL) {
+ rc = -ENOTCONN;
+ goto error;
+ }
+
+ rc = dev->ops->activate_target(dev, target, protocol);
if (!rc) {
- dev->activated_target_idx = target_idx;
+ dev->active_target = target;
if (dev->ops->check_presence)
mod_timer(&dev->check_pres_timer, jiffies +
@@ -327,11 +361,21 @@ int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
goto error;
}
+ if (dev->active_target == NULL) {
+ rc = -ENOTCONN;
+ goto error;
+ }
+
+ if (dev->active_target->idx != target_idx) {
+ rc = -ENOTCONN;
+ goto error;
+ }
+
if (dev->ops->check_presence)
del_timer_sync(&dev->check_pres_timer);
- dev->ops->deactivate_target(dev, target_idx);
- dev->activated_target_idx = NFC_TARGET_IDX_NONE;
+ dev->ops->deactivate_target(dev, dev->active_target);
+ dev->active_target = NULL;
error:
device_unlock(&dev->dev);
@@ -365,13 +409,13 @@ int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
goto error;
}
- if (dev->activated_target_idx == NFC_TARGET_IDX_NONE) {
+ if (dev->active_target == NULL) {
rc = -ENOTCONN;
kfree_skb(skb);
goto error;
}
- if (target_idx != dev->activated_target_idx) {
+ if (dev->active_target->idx != target_idx) {
rc = -EADDRNOTAVAIL;
kfree_skb(skb);
goto error;
@@ -380,7 +424,8 @@ int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
if (dev->ops->check_presence)
del_timer_sync(&dev->check_pres_timer);
- rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context);
+ rc = dev->ops->data_exchange(dev, dev->active_target, skb, cb,
+ cb_context);
if (!rc && dev->ops->check_presence)
mod_timer(&dev->check_pres_timer, jiffies +
@@ -456,6 +501,9 @@ EXPORT_SYMBOL(nfc_alloc_recv_skb);
* The device driver must call this function when one or many nfc targets
* are found. After calling this function, the device driver must stop
* polling for targets.
+ * IMPORTANT: this function must not be called from an atomic context.
+ * In addition, it must also not be called from a context that would prevent
+ * the NFC Core to call other nfc ops entry point concurrently.
*/
int nfc_targets_found(struct nfc_dev *dev,
struct nfc_target *targets, int n_targets)
@@ -469,7 +517,7 @@ int nfc_targets_found(struct nfc_dev *dev,
for (i = 0; i < n_targets; i++)
targets[i].idx = dev->target_next_idx++;
- spin_lock_bh(&dev->targets_lock);
+ device_lock(&dev->dev);
dev->targets_generation++;
@@ -479,12 +527,12 @@ int nfc_targets_found(struct nfc_dev *dev,
if (!dev->targets) {
dev->n_targets = 0;
- spin_unlock_bh(&dev->targets_lock);
+ device_unlock(&dev->dev);
return -ENOMEM;
}
dev->n_targets = n_targets;
- spin_unlock_bh(&dev->targets_lock);
+ device_unlock(&dev->dev);
nfc_genl_targets_found(dev);
@@ -492,6 +540,18 @@ int nfc_targets_found(struct nfc_dev *dev,
}
EXPORT_SYMBOL(nfc_targets_found);
+/**
+ * nfc_target_lost - inform that an activated target went out of field
+ *
+ * @dev: The nfc device that had the activated target in field
+ * @target_idx: the nfc index of the target
+ *
+ * The device driver must call this function when the activated target
+ * goes out of the field.
+ * IMPORTANT: this function must not be called from an atomic context.
+ * In addition, it must also not be called from a context that would prevent
+ * the NFC Core to call other nfc ops entry point concurrently.
+ */
int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
{
struct nfc_target *tg;
@@ -499,7 +559,7 @@ int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
- spin_lock_bh(&dev->targets_lock);
+ device_lock(&dev->dev);
for (i = 0; i < dev->n_targets; i++) {
tg = &dev->targets[i];
@@ -508,13 +568,13 @@ int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
}
if (i == dev->n_targets) {
- spin_unlock_bh(&dev->targets_lock);
+ device_unlock(&dev->dev);
return -EINVAL;
}
dev->targets_generation++;
dev->n_targets--;
- dev->activated_target_idx = NFC_TARGET_IDX_NONE;
+ dev->active_target = NULL;
if (dev->n_targets) {
memcpy(&dev->targets[i], &dev->targets[i + 1],
@@ -524,7 +584,7 @@ int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
dev->targets = NULL;
}
- spin_unlock_bh(&dev->targets_lock);
+ device_unlock(&dev->dev);
nfc_genl_target_lost(dev, target_idx);
@@ -556,15 +616,16 @@ static void nfc_check_pres_work(struct work_struct *work)
device_lock(&dev->dev);
- if (dev->activated_target_idx != NFC_TARGET_IDX_NONE &&
- timer_pending(&dev->check_pres_timer) == 0) {
- rc = dev->ops->check_presence(dev, dev->activated_target_idx);
+ if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) {
+ rc = dev->ops->check_presence(dev, dev->active_target);
if (!rc) {
mod_timer(&dev->check_pres_timer, jiffies +
msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
} else {
- nfc_target_lost(dev, dev->activated_target_idx);
- dev->activated_target_idx = NFC_TARGET_IDX_NONE;
+ u32 active_target_idx = dev->active_target->idx;
+ device_unlock(&dev->dev);
+ nfc_target_lost(dev, active_target_idx);
+ return;
}
}
@@ -637,14 +698,12 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
dev->tx_headroom = tx_headroom;
dev->tx_tailroom = tx_tailroom;
- spin_lock_init(&dev->targets_lock);
nfc_genl_data_init(&dev->genl_data);
+
/* first generation must not be 0 */
dev->targets_generation = 1;
- dev->activated_target_idx = NFC_TARGET_IDX_NONE;
-
if (ops->check_presence) {
char name[32];
init_timer(&dev->check_pres_timer);
@@ -662,7 +721,6 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
}
}
-
return dev;
}
EXPORT_SYMBOL(nfc_allocate_device);