From f36214408470ecf6a052e76b72d05b2328b60fcf Mon Sep 17 00:00:00 2001 From: "sjur.brandeland@stericsson.com" Date: Fri, 13 May 2011 02:44:01 +0000 Subject: [PATCH] caif: Use RCU and lists in cfcnfg.c for managing caif link layers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RCU lists are used for handling the link layers instead of array. When generating CAIF phy-id, ifindex is used as base. Legal range is 1-6. Introduced set_phy_state() for managing CAIF Link layer state. Signed-off-by: Sjur Brændeland Signed-off-by: David S. Miller --- net/caif/cfcnfg.c | 377 ++++++++++++++++++++++++++-------------------- 1 file changed, 215 insertions(+), 162 deletions(-) diff --git a/net/caif/cfcnfg.c b/net/caif/cfcnfg.c index 25c0b198e285..7892cc084e27 100644 --- a/net/caif/cfcnfg.c +++ b/net/caif/cfcnfg.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -18,11 +19,7 @@ #include #include #include - -#include -#include - -#define MAX_PHY_LAYERS 7 +#include #define container_obj(layr) container_of(layr, struct cfcnfg, layer) @@ -30,6 +27,9 @@ * to manage physical interfaces */ struct cfcnfg_phyinfo { + struct list_head node; + bool up; + /* Pointer to the layer below the MUX (framing layer) */ struct cflayer *frm_layer; /* Pointer to the lowest actual physical layer */ @@ -39,9 +39,6 @@ struct cfcnfg_phyinfo { /* Preference of the physical in interface */ enum cfcnfg_phy_preference pref; - /* Reference count, number of channels using the device */ - int phy_ref_count; - /* Information about the physical device */ struct dev_info dev_info; @@ -59,8 +56,8 @@ struct cfcnfg { struct cflayer layer; struct cflayer *ctrl; struct cflayer *mux; - u8 last_phyid; - struct cfcnfg_phyinfo phy_layers[MAX_PHY_LAYERS]; + struct list_head phys; + struct mutex lock; }; static void cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, @@ -76,6 +73,9 @@ struct cfcnfg *cfcnfg_create(void) { struct cfcnfg *this; struct cfctrl_rsp *resp; + + might_sleep(); + /* Initiate this layer */ this = kzalloc(sizeof(struct cfcnfg), GFP_ATOMIC); if (!this) { @@ -99,15 +99,19 @@ struct cfcnfg *cfcnfg_create(void) resp->radioset_rsp = cfctrl_resp_func; resp->linksetup_rsp = cfcnfg_linkup_rsp; resp->reject_rsp = cfcnfg_reject_rsp; - - this->last_phyid = 1; + INIT_LIST_HEAD(&this->phys); cfmuxl_set_uplayer(this->mux, this->ctrl, 0); layer_set_dn(this->ctrl, this->mux); layer_set_up(this->ctrl, this); + mutex_init(&this->lock); + return this; out_of_mem: pr_warn("Out of memory\n"); + + synchronize_rcu(); + kfree(this->mux); kfree(this->ctrl); kfree(this); @@ -117,7 +121,10 @@ EXPORT_SYMBOL(cfcnfg_create); void cfcnfg_remove(struct cfcnfg *cfg) { + might_sleep(); if (cfg) { + synchronize_rcu(); + kfree(cfg->mux); kfree(cfg->ctrl); kfree(cfg); @@ -128,6 +135,17 @@ static void cfctrl_resp_func(void) { } +static struct cfcnfg_phyinfo *cfcnfg_get_phyinfo_rcu(struct cfcnfg *cnfg, + u8 phyid) +{ + struct cfcnfg_phyinfo *phy; + + list_for_each_entry_rcu(phy, &cnfg->phys, node) + if (phy->id == phyid) + return phy; + return NULL; +} + static void cfctrl_enum_resp(void) { } @@ -135,106 +153,65 @@ static void cfctrl_enum_resp(void) struct dev_info *cfcnfg_get_phyid(struct cfcnfg *cnfg, enum cfcnfg_phy_preference phy_pref) { - u16 i; - /* Try to match with specified preference */ - for (i = 1; i < MAX_PHY_LAYERS; i++) { - if (cnfg->phy_layers[i].id == i && - cnfg->phy_layers[i].pref == phy_pref && - cnfg->phy_layers[i].frm_layer != NULL) { - caif_assert(cnfg->phy_layers != NULL); - caif_assert(cnfg->phy_layers[i].id == i); - return &cnfg->phy_layers[i].dev_info; - } + struct cfcnfg_phyinfo *phy; + + list_for_each_entry_rcu(phy, &cnfg->phys, node) { + if (phy->up && phy->pref == phy_pref && + phy->frm_layer != NULL) + + return &phy->dev_info; } + /* Otherwise just return something */ - for (i = 1; i < MAX_PHY_LAYERS; i++) { - if (cnfg->phy_layers[i].id == i) { - caif_assert(cnfg->phy_layers != NULL); - caif_assert(cnfg->phy_layers[i].id == i); - return &cnfg->phy_layers[i].dev_info; - } - } + list_for_each_entry_rcu(phy, &cnfg->phys, node) + if (phy->up) + return &phy->dev_info; return NULL; } -static struct cfcnfg_phyinfo *cfcnfg_get_phyinfo(struct cfcnfg *cnfg, - u8 phyid) -{ - int i; - /* Try to match with specified preference */ - for (i = 0; i < MAX_PHY_LAYERS; i++) - if (cnfg->phy_layers[i].frm_layer != NULL && - cnfg->phy_layers[i].id == phyid) - return &cnfg->phy_layers[i]; - return NULL; -} - - int cfcnfg_get_id_from_ifi(struct cfcnfg *cnfg, int ifi) { - int i; - for (i = 0; i < MAX_PHY_LAYERS; i++) - if (cnfg->phy_layers[i].frm_layer != NULL && - cnfg->phy_layers[i].ifindex == ifi) - return i; + struct cfcnfg_phyinfo *phy; + + list_for_each_entry_rcu(phy, &cnfg->phys, node) + if (phy->ifindex == ifi && phy->up) + return phy->id; return -ENODEV; } -int cfcnfg_disconn_adapt_layer(struct cfcnfg *cnfg, struct cflayer *adap_layer) +int cfcnfg_disconn_adapt_layer(struct cfcnfg *cfg, struct cflayer *adap_layer) { u8 channel_id = 0; int ret = 0; struct cflayer *servl = NULL; - struct cfcnfg_phyinfo *phyinfo = NULL; - u8 phyid = 0; caif_assert(adap_layer != NULL); + channel_id = adap_layer->id; if (adap_layer->dn == NULL || channel_id == 0) { pr_err("adap_layer->dn == NULL or adap_layer->id is 0\n"); ret = -ENOTCONN; goto end; } - servl = cfmuxl_remove_uplayer(cnfg->mux, channel_id); + + servl = cfmuxl_remove_uplayer(cfg->mux, channel_id); if (servl == NULL) { - pr_err("PROTOCOL ERROR - Error removing service_layer Channel_Id(%d)", - channel_id); + pr_err("PROTOCOL ERROR - " + "Error removing service_layer Channel_Id(%d)", + channel_id); ret = -EINVAL; goto end; } - layer_set_up(servl, NULL); - ret = cfctrl_linkdown_req(cnfg->ctrl, channel_id, adap_layer); - if (ret) - goto end; - caif_assert(channel_id == servl->id); - if (adap_layer->dn != NULL) { - phyid = cfsrvl_getphyid(adap_layer->dn); - phyinfo = cfcnfg_get_phyinfo(cnfg, phyid); - if (phyinfo == NULL) { - pr_warn("No interface to send disconnect to\n"); - ret = -ENODEV; - goto end; - } - if (phyinfo->id != phyid || - phyinfo->phy_layer->id != phyid || - phyinfo->frm_layer->id != phyid) { - pr_err("Inconsistency in phy registration\n"); - ret = -EINVAL; - goto end; - } - } - if (phyinfo != NULL && --phyinfo->phy_ref_count == 0 && - phyinfo->phy_layer != NULL && - phyinfo->phy_layer->modemcmd != NULL) { - phyinfo->phy_layer->modemcmd(phyinfo->phy_layer, - _CAIF_MODEMCMD_PHYIF_USELESS); - } + ret = cfctrl_linkdown_req(cfg->ctrl, channel_id, adap_layer); + end: - cfsrvl_put(servl); - cfctrl_cancel_req(cnfg->ctrl, adap_layer); + cfctrl_cancel_req(cfg->ctrl, adap_layer); + + /* Do RCU sync before initiating cleanup */ + synchronize_rcu(); if (adap_layer->ctrlcmd != NULL) adap_layer->ctrlcmd(adap_layer, CAIF_CTRLCMD_DEINIT_RSP, 0); return ret; @@ -269,39 +246,56 @@ int cfcnfg_add_adaptation_layer(struct cfcnfg *cnfg, int *proto_tail) { struct cflayer *frml; + struct cfcnfg_phyinfo *phy; + int err; + + rcu_read_lock(); + phy = cfcnfg_get_phyinfo_rcu(cnfg, param->phyid); + if (!phy) { + err = -ENODEV; + goto unlock; + } + err = -EINVAL; + if (adap_layer == NULL) { pr_err("adap_layer is zero\n"); - return -EINVAL; + goto unlock; } if (adap_layer->receive == NULL) { pr_err("adap_layer->receive is NULL\n"); - return -EINVAL; + goto unlock; } if (adap_layer->ctrlcmd == NULL) { pr_err("adap_layer->ctrlcmd == NULL\n"); - return -EINVAL; + goto unlock; } - frml = cnfg->phy_layers[param->phyid].frm_layer; + + err = -ENODEV; + frml = phy->frm_layer; if (frml == NULL) { pr_err("Specified PHY type does not exist!\n"); - return -ENODEV; + goto unlock; } - caif_assert(param->phyid == cnfg->phy_layers[param->phyid].id); - caif_assert(cnfg->phy_layers[param->phyid].frm_layer->id == + caif_assert(param->phyid == phy->id); + caif_assert(phy->frm_layer->id == param->phyid); - caif_assert(cnfg->phy_layers[param->phyid].phy_layer->id == + caif_assert(phy->phy_layer->id == param->phyid); - *ifindex = cnfg->phy_layers[param->phyid].ifindex; - *proto_head = - protohead[param->linktype]+ - (cnfg->phy_layers[param->phyid].use_stx ? 1 : 0); - + *ifindex = phy->ifindex; *proto_tail = 2; + *proto_head = + protohead[param->linktype] + (phy->use_stx ? 1 : 0); + + rcu_read_unlock(); /* FIXME: ENUMERATE INITIALLY WHEN ACTIVATING PHYSICAL INTERFACE */ cfctrl_enum_req(cnfg->ctrl, param->phyid); return cfctrl_linkup_request(cnfg->ctrl, param, adap_layer); + +unlock: + rcu_read_unlock(); + return err; } EXPORT_SYMBOL(cfcnfg_add_adaptation_layer); @@ -315,32 +309,37 @@ static void cfcnfg_reject_rsp(struct cflayer *layer, u8 channel_id, static void cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv, - u8 phyid, struct cflayer *adapt_layer) + u8 phyid, struct cflayer *adapt_layer) { struct cfcnfg *cnfg = container_obj(layer); struct cflayer *servicel = NULL; struct cfcnfg_phyinfo *phyinfo; struct net_device *netdev; + rcu_read_lock(); + if (adapt_layer == NULL) { - pr_debug("link setup response but no client exist, send linkdown back\n"); + pr_debug("link setup response but no client exist," + "send linkdown back\n"); cfctrl_linkdown_req(cnfg->ctrl, channel_id, NULL); - return; + goto unlock; } caif_assert(cnfg != NULL); caif_assert(phyid != 0); - phyinfo = &cnfg->phy_layers[phyid]; + + phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid); + if (phyinfo == NULL) { + pr_err("ERROR: Link Layer Device dissapeared" + "while connecting\n"); + goto unlock; + } + + caif_assert(phyinfo != NULL); caif_assert(phyinfo->id == phyid); caif_assert(phyinfo->phy_layer != NULL); caif_assert(phyinfo->phy_layer->id == phyid); - phyinfo->phy_ref_count++; - if (phyinfo->phy_ref_count == 1 && - phyinfo->phy_layer->modemcmd != NULL) { - phyinfo->phy_layer->modemcmd(phyinfo->phy_layer, - _CAIF_MODEMCMD_PHYIF_USEFULL); - } adapt_layer->id = channel_id; switch (serv) { @@ -348,7 +347,8 @@ cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv, servicel = cfvei_create(channel_id, &phyinfo->dev_info); break; case CFCTRL_SRV_DATAGRAM: - servicel = cfdgml_create(channel_id, &phyinfo->dev_info); + servicel = cfdgml_create(channel_id, + &phyinfo->dev_info); break; case CFCTRL_SRV_RFM: netdev = phyinfo->dev_info.dev; @@ -365,94 +365,93 @@ cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv, servicel = cfdbgl_create(channel_id, &phyinfo->dev_info); break; default: - pr_err("Protocol error. Link setup response - unknown channel type\n"); - return; + pr_err("Protocol error. Link setup response " + "- unknown channel type\n"); + goto unlock; } if (!servicel) { pr_warn("Out of memory\n"); - return; + goto unlock; } layer_set_dn(servicel, cnfg->mux); cfmuxl_set_uplayer(cnfg->mux, servicel, channel_id); layer_set_up(servicel, adapt_layer); layer_set_dn(adapt_layer, servicel); - cfsrvl_get(servicel); + + rcu_read_unlock(); + servicel->ctrlcmd(servicel, CAIF_CTRLCMD_INIT_RSP, 0); + return; +unlock: + rcu_read_unlock(); } void cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type, struct net_device *dev, struct cflayer *phy_layer, - u16 *phyid, enum cfcnfg_phy_preference pref, + u16 *phy_id, enum cfcnfg_phy_preference pref, bool fcs, bool stx) { struct cflayer *frml; struct cflayer *phy_driver = NULL; + struct cfcnfg_phyinfo *phyinfo; int i; + u8 phyid; + mutex_lock(&cnfg->lock); - if (cnfg->phy_layers[cnfg->last_phyid].frm_layer == NULL) { - *phyid = cnfg->last_phyid; - - /* range: * 1..(MAX_PHY_LAYERS-1) */ - cnfg->last_phyid = - (cnfg->last_phyid % (MAX_PHY_LAYERS - 1)) + 1; - } else { - *phyid = 0; - for (i = 1; i < MAX_PHY_LAYERS; i++) { - if (cnfg->phy_layers[i].frm_layer == NULL) { - *phyid = i; - break; - } - } - } - if (*phyid == 0) { - pr_err("No Available PHY ID\n"); - return; + /* CAIF protocol allow maximum 6 link-layers */ + for (i = 0; i < 7; i++) { + phyid = (dev->ifindex + i) & 0x7; + if (phyid == 0) + continue; + if (cfcnfg_get_phyinfo_rcu(cnfg, phyid) == NULL) + goto got_phyid; } + pr_warn("Too many CAIF Link Layers (max 6)\n"); + goto out; + +got_phyid: + phyinfo = kzalloc(sizeof(struct cfcnfg_phyinfo), GFP_ATOMIC); switch (phy_type) { case CFPHYTYPE_FRAG: phy_driver = - cfserl_create(CFPHYTYPE_FRAG, *phyid, stx); + cfserl_create(CFPHYTYPE_FRAG, phyid, stx); if (!phy_driver) { pr_warn("Out of memory\n"); - return; + goto out; } - break; case CFPHYTYPE_CAIF: phy_driver = NULL; break; default: - pr_err("%d\n", phy_type); - return; - break; + goto out; } - - phy_layer->id = *phyid; - cnfg->phy_layers[*phyid].pref = pref; - cnfg->phy_layers[*phyid].id = *phyid; - cnfg->phy_layers[*phyid].dev_info.id = *phyid; - cnfg->phy_layers[*phyid].dev_info.dev = dev; - cnfg->phy_layers[*phyid].phy_layer = phy_layer; - cnfg->phy_layers[*phyid].phy_ref_count = 0; - cnfg->phy_layers[*phyid].ifindex = dev->ifindex; - cnfg->phy_layers[*phyid].use_stx = stx; - cnfg->phy_layers[*phyid].use_fcs = fcs; + phy_layer->id = phyid; + phyinfo->pref = pref; + phyinfo->id = phyid; + phyinfo->dev_info.id = phyid; + phyinfo->dev_info.dev = dev; + phyinfo->phy_layer = phy_layer; + phyinfo->ifindex = dev->ifindex; + phyinfo->use_stx = stx; + phyinfo->use_fcs = fcs; phy_layer->type = phy_type; - frml = cffrml_create(*phyid, fcs); + frml = cffrml_create(phyid, fcs); + if (!frml) { pr_warn("Out of memory\n"); - return; + kfree(phyinfo); + goto out; } - cnfg->phy_layers[*phyid].frm_layer = frml; - cfmuxl_set_dnlayer(cnfg->mux, frml, *phyid); + phyinfo->frm_layer = frml; layer_set_up(frml, cnfg->mux); if (phy_driver != NULL) { - phy_driver->id = *phyid; + phy_driver->id = phyid; layer_set_dn(frml, phy_driver); layer_set_up(phy_driver, frml); layer_set_dn(phy_driver, phy_layer); @@ -461,33 +460,87 @@ cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type, layer_set_dn(frml, phy_layer); layer_set_up(phy_layer, frml); } + + list_add_rcu(&phyinfo->node, &cnfg->phys); +out: + mutex_unlock(&cnfg->lock); } EXPORT_SYMBOL(cfcnfg_add_phy_layer); +int cfcnfg_set_phy_state(struct cfcnfg *cnfg, struct cflayer *phy_layer, + bool up) +{ + struct cfcnfg_phyinfo *phyinfo; + + rcu_read_lock(); + phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phy_layer->id); + if (phyinfo == NULL) { + rcu_read_unlock(); + return -ENODEV; + } + + if (phyinfo->up == up) { + rcu_read_unlock(); + return 0; + } + phyinfo->up = up; + + if (up) { + cffrml_hold(phyinfo->frm_layer); + cfmuxl_set_dnlayer(cnfg->mux, phyinfo->frm_layer, + phy_layer->id); + } else { + cfmuxl_remove_dnlayer(cnfg->mux, phy_layer->id); + cffrml_put(phyinfo->frm_layer); + } + + rcu_read_unlock(); + return 0; +} +EXPORT_SYMBOL(cfcnfg_set_phy_state); + int cfcnfg_del_phy_layer(struct cfcnfg *cnfg, struct cflayer *phy_layer) { struct cflayer *frml, *frml_dn; u16 phyid; - phyid = phy_layer->id; - caif_assert(phyid == cnfg->phy_layers[phyid].id); - caif_assert(phy_layer == cnfg->phy_layers[phyid].phy_layer); - caif_assert(phy_layer->id == phyid); - caif_assert(cnfg->phy_layers[phyid].frm_layer->id == phyid); + struct cfcnfg_phyinfo *phyinfo; - memset(&cnfg->phy_layers[phy_layer->id], 0, - sizeof(struct cfcnfg_phyinfo)); - frml = cfmuxl_remove_dnlayer(cnfg->mux, phy_layer->id); + might_sleep(); + + mutex_lock(&cnfg->lock); + + phyid = phy_layer->id; + phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid); + + if (phyinfo == NULL) + return 0; + caif_assert(phyid == phyinfo->id); + caif_assert(phy_layer == phyinfo->phy_layer); + caif_assert(phy_layer->id == phyid); + caif_assert(phyinfo->frm_layer->id == phyid); + + list_del_rcu(&phyinfo->node); + synchronize_rcu(); + + frml = phyinfo->frm_layer; frml_dn = frml->dn; cffrml_set_uplayer(frml, NULL); cffrml_set_dnlayer(frml, NULL); - kfree(frml); - if (phy_layer != frml_dn) { layer_set_up(frml_dn, NULL); layer_set_dn(frml_dn, NULL); - kfree(frml_dn); } layer_set_up(phy_layer, NULL); + + + + if (phyinfo->phy_layer != frml_dn) + kfree(frml_dn); + + kfree(frml); + kfree(phyinfo); + mutex_unlock(&cnfg->lock); + return 0; } EXPORT_SYMBOL(cfcnfg_del_phy_layer);