From patchwork Thu Jan 7 11:04:59 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 43530 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 2F28CB7C48 for ; Sat, 23 Jan 2010 10:24:53 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755424Ab0AVXXs (ORCPT ); Fri, 22 Jan 2010 18:23:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755917Ab0AVXXq (ORCPT ); Fri, 22 Jan 2010 18:23:46 -0500 Received: from fmmailgate01.web.de ([217.72.192.221]:39128 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754131Ab0AVXW0 (ORCPT ); Fri, 22 Jan 2010 18:22:26 -0500 Received: from smtp08.web.de (fmsmtp08.dlan.cinetic.de [172.20.5.216]) by fmmailgate01.web.de (Postfix) with ESMTP id 7705A1456CEFA; Sat, 23 Jan 2010 00:22:25 +0100 (CET) Received: from [92.75.141.69] (helo=[192.168.1.10]) by smtp08.web.de with asmtp (TLSv1:AES256-SHA:256) (WEB.DE 4.110 #314) id 1NYSpc-0006Au-00; Sat, 23 Jan 2010 00:22:25 +0100 Message-Id: <97a7c858e6cef8ff9996295f097d14136d2ec59a.1264201406.git.jan.kiszka@web.de> In-Reply-To: References: From: Jan Kiszka To: David Miller , Karsten Keil Cc: linux-kernel@vger.kernel.org, i4ldeveloper@listserv.isdn4linux.de, isdn4linux@listserv.isdn4linux.de, netdev@vger.kernel.org Date: Thu, 7 Jan 2010 12:04:59 +0100 Subject: [PATCH 10/31] CAPI: Rework locking of controller data structures X-Sender: jan.kiszka@web.de X-Provags-ID: V01U2FsdGVkX1+VCnmXwQyMPdUrLeGoRNCSvweG0PTPq42CGERM xphlFQ6LKSR7P+ssveQ1BaQGd7DE9eHDLecbf6GRrC8MOVMvC2 V8VboLiec= Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch applies the mutex so far only protecting the controller list to (almost) all accesses of controller data structures. Signed-off-by: Jan Kiszka --- drivers/isdn/capi/kcapi.c | 259 +++++++++++++++++++++++++++------------- drivers/isdn/capi/kcapi.h | 4 +- drivers/isdn/capi/kcapi_proc.c | 5 + 3 files changed, 186 insertions(+), 82 deletions(-) diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c index 0fda05d..964650a 100644 --- a/drivers/isdn/capi/kcapi.c +++ b/drivers/isdn/capi/kcapi.c @@ -61,11 +61,12 @@ static char capi_manufakturer[64] = "AVM Berlin"; LIST_HEAD(capi_drivers); DEFINE_MUTEX(capi_drivers_lock); +struct capi_ctr *capi_controller[CAPI_MAXCONTR]; +DEFINE_MUTEX(capi_controller_lock); + static DEFINE_RWLOCK(application_lock); -static DEFINE_MUTEX(controller_mutex); struct capi20_appl *capi_applications[CAPI_MAXAPPL]; -struct capi_ctr *capi_controller[CAPI_MAXCONTR]; static int ncontrollers; @@ -171,13 +172,15 @@ static void notify_up(u32 contr) struct capi_ctr *ctr; u16 applid; + mutex_lock(&capi_controller_lock); + if (showcapimsgs & 1) printk(KERN_DEBUG "kcapi: notify up contr %dn", contr); ctr = get_capi_ctr_by_nr(contr); if (ctr) { if (ctr->state == CAPI_CTR_RUNNING) - return; + goto unlock_out; ctr->state = CAPI_CTR_RUNNING; @@ -189,6 +192,9 @@ static void notify_up(u32 contr) } } else printk(KERN_WARNING "%s: invalid contr %dn", __func__, contr); + +unlock_out: + mutex_unlock(&capi_controller_lock); } static void ctr_down(struct capi_ctr *ctr) @@ -217,6 +223,8 @@ static void notify_down(u32 contr) { struct capi_ctr *ctr; + mutex_lock(&capi_controller_lock); + if (showcapimsgs & 1) printk(KERN_DEBUG "kcapi: notify down contr %dn", contr); @@ -225,6 +233,8 @@ static void notify_down(u32 contr) ctr_down(ctr); else printk(KERN_WARNING "%s: invalid contr %dn", __func__, contr); + + mutex_unlock(&capi_controller_lock); } static int @@ -481,21 +491,19 @@ int attach_capi_ctr(struct capi_ctr *ctr) { int i; - mutex_lock(&controller_mutex); + mutex_lock(&capi_controller_lock); for (i = 0; i < CAPI_MAXCONTR; i++) { if (!capi_controller[i]) break; } if (i == CAPI_MAXCONTR) { - mutex_unlock(&controller_mutex); + mutex_unlock(&capi_controller_lock); printk(KERN_ERR "kcapi: out of controller slotsn"); return -EBUSY; } capi_controller[i] = ctr; - mutex_unlock(&controller_mutex); - ctr->nrecvctlpkt = 0; ctr->nrecvdatapkt = 0; ctr->nsentctlpkt = 0; @@ -513,6 +521,9 @@ int attach_capi_ctr(struct capi_ctr *ctr) } ncontrollers++; + + mutex_unlock(&capi_controller_lock); + printk(KERN_NOTICE "kcapi: controller [%03d]: %s attachedn", ctr->cnr, ctr->name); return 0; @@ -531,19 +542,29 @@ EXPORT_SYMBOL(attach_capi_ctr); int detach_capi_ctr(struct capi_ctr *ctr) { + int err = 0; + + mutex_lock(&capi_controller_lock); + ctr_down(ctr); + if (capi_controller[ctr->cnr - 1] != ctr) { + err = -EINVAL; + goto unlock_out; + } + capi_controller[ctr->cnr - 1] = NULL; ncontrollers--; - if (ctr->procent) { + if (ctr->procent) remove_proc_entry(ctr->procfn, NULL); - ctr->procent = NULL; - } - capi_controller[ctr->cnr - 1] = NULL; + printk(KERN_NOTICE "kcapi: controller [%03d]: %s unregisteredn", ctr->cnr, ctr->name); - return 0; +unlock_out: + mutex_unlock(&capi_controller_lock); + + return err; } EXPORT_SYMBOL(detach_capi_ctr); @@ -593,13 +614,21 @@ EXPORT_SYMBOL(unregister_capi_driver); u16 capi20_isinstalled(void) { + u16 ret = CAPI_REGNOTINSTALLED; int i; - for (i = 0; i < CAPI_MAXCONTR; i++) { + + mutex_lock(&capi_controller_lock); + + for (i = 0; i < CAPI_MAXCONTR; i++) if (capi_controller[i] && - capi_controller[i]->state == CAPI_CTR_RUNNING) - return CAPI_NOERROR; - } - return CAPI_REGNOTINSTALLED; + capi_controller[i]->state == CAPI_CTR_RUNNING) { + ret = CAPI_NOERROR; + break; + } + + mutex_unlock(&capi_controller_lock); + + return ret; } EXPORT_SYMBOL(capi20_isinstalled); @@ -652,14 +681,16 @@ u16 capi20_register(struct capi20_appl *ap) write_unlock_irqrestore(&application_lock, flags); - mutex_lock(&controller_mutex); + mutex_lock(&capi_controller_lock); + for (i = 0; i < CAPI_MAXCONTR; i++) { if (!capi_controller[i] || capi_controller[i]->state != CAPI_CTR_RUNNING) continue; register_appl(capi_controller[i], applid, &ap->rparam); } - mutex_unlock(&controller_mutex); + + mutex_unlock(&capi_controller_lock); if (showcapimsgs & 1) { printk(KERN_DEBUG "kcapi: appl %d upn", applid); @@ -692,14 +723,16 @@ u16 capi20_release(struct capi20_appl *ap) capi_applications[ap->applid - 1] = NULL; write_unlock_irqrestore(&application_lock, flags); - mutex_lock(&controller_mutex); + mutex_lock(&capi_controller_lock); + for (i = 0; i < CAPI_MAXCONTR; i++) { if (!capi_controller[i] || capi_controller[i]->state != CAPI_CTR_RUNNING) continue; release_appl(capi_controller[i], ap->applid); } - mutex_unlock(&controller_mutex); + + mutex_unlock(&capi_controller_lock); flush_scheduled_work(); skb_queue_purge(&ap->recv_queue); @@ -738,6 +771,12 @@ u16 capi20_put_message(struct capi20_appl *ap, struct sk_buff *skb) || !capi_cmd_valid(CAPIMSG_COMMAND(skb->data)) || !capi_subcmd_valid(CAPIMSG_SUBCOMMAND(skb->data))) return CAPI_ILLCMDORSUBCMDORMSGTOSMALL; + + /* + * The controller reference is protected by the existence of the + * application passed to us. We assume that the caller properly + * synchronizes this service with capi20_release. + */ ctr = get_capi_ctr_by_nr(CAPIMSG_CONTROLLER(skb->data)); if (!ctr || ctr->state != CAPI_CTR_RUNNING) { ctr = get_capi_ctr_by_nr(1); /* XXX why? */ @@ -802,16 +841,24 @@ EXPORT_SYMBOL(capi20_put_message); u16 capi20_get_manufacturer(u32 contr, u8 *buf) { struct capi_ctr *ctr; + u16 ret; if (contr == 0) { strlcpy(buf, capi_manufakturer, CAPI_MANUFACTURER_LEN); return CAPI_NOERROR; } + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(contr); - if (!ctr || ctr->state != CAPI_CTR_RUNNING) - return CAPI_REGNOTINSTALLED; - strlcpy(buf, ctr->manu, CAPI_MANUFACTURER_LEN); - return CAPI_NOERROR; + if (ctr && ctr->state == CAPI_CTR_RUNNING) { + strlcpy(buf, ctr->manu, CAPI_MANUFACTURER_LEN); + ret = CAPI_NOERROR; + } else + ret = CAPI_REGNOTINSTALLED; + + mutex_unlock(&capi_controller_lock); + return ret; } EXPORT_SYMBOL(capi20_get_manufacturer); @@ -829,17 +876,24 @@ EXPORT_SYMBOL(capi20_get_manufacturer); u16 capi20_get_version(u32 contr, struct capi_version *verp) { struct capi_ctr *ctr; + u16 ret; if (contr == 0) { *verp = driver_version; return CAPI_NOERROR; } + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(contr); - if (!ctr || ctr->state != CAPI_CTR_RUNNING) - return CAPI_REGNOTINSTALLED; + if (ctr && ctr->state == CAPI_CTR_RUNNING) { + memcpy(verp, &ctr->version, sizeof(capi_version)); + ret = CAPI_NOERROR; + } else + ret = CAPI_REGNOTINSTALLED; - memcpy(verp, &ctr->version, sizeof(capi_version)); - return CAPI_NOERROR; + mutex_unlock(&capi_controller_lock); + return ret; } EXPORT_SYMBOL(capi20_get_version); @@ -857,17 +911,24 @@ EXPORT_SYMBOL(capi20_get_version); u16 capi20_get_serial(u32 contr, u8 *serial) { struct capi_ctr *ctr; + u16 ret; if (contr == 0) { strlcpy(serial, driver_serial, CAPI_SERIAL_LEN); return CAPI_NOERROR; } + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(contr); - if (!ctr || ctr->state != CAPI_CTR_RUNNING) - return CAPI_REGNOTINSTALLED; + if (ctr && ctr->state == CAPI_CTR_RUNNING) { + strlcpy(serial, ctr->serial, CAPI_SERIAL_LEN); + ret = CAPI_NOERROR; + } else + ret = CAPI_REGNOTINSTALLED; - strlcpy(serial, ctr->serial, CAPI_SERIAL_LEN); - return CAPI_NOERROR; + mutex_unlock(&capi_controller_lock); + return ret; } EXPORT_SYMBOL(capi20_get_serial); @@ -885,21 +946,53 @@ EXPORT_SYMBOL(capi20_get_serial); u16 capi20_get_profile(u32 contr, struct capi_profile *profp) { struct capi_ctr *ctr; + u16 ret; if (contr == 0) { profp->ncontroller = ncontrollers; return CAPI_NOERROR; } + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(contr); - if (!ctr || ctr->state != CAPI_CTR_RUNNING) - return CAPI_REGNOTINSTALLED; + if (ctr && ctr->state == CAPI_CTR_RUNNING) { + memcpy(profp, &ctr->profile, sizeof(struct capi_profile)); + ret = CAPI_NOERROR; + } else + ret = CAPI_REGNOTINSTALLED; - memcpy(profp, &ctr->profile, sizeof(struct capi_profile)); - return CAPI_NOERROR; + mutex_unlock(&capi_controller_lock); + return ret; } EXPORT_SYMBOL(capi20_get_profile); +/* Must be called with capi_controller_lock held. */ +static int wait_on_ctr_state(struct capi_ctr *ctr, unsigned int state) +{ + int cnr = ctr->cnr; + int retval = 0; + + while (ctr->state != state) { + mutex_unlock(&capi_controller_lock); + + msleep_interruptible(100); /* 0.1 sec */ + + mutex_lock(&capi_controller_lock); + + if (signal_pending(current)) { + retval = -EINTR; + break; + } + if (ctr != get_capi_ctr_by_nr(cnr)) { + retval = -ESRCH; + break; + } + } + return retval; +} + #ifdef AVMB1_COMPAT static int old_capi_manufacturer(unsigned int cmd, void __user *data) { @@ -977,27 +1070,30 @@ static int old_capi_manufacturer(unsigned int cmd, void __user *data) sizeof(avmb1_loadandconfigdef))) return -EFAULT; } + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(ldef.contr); - if (!ctr) - return -EINVAL; - ctr = capi_ctr_get(ctr); - if (!ctr) - return -ESRCH; + if (!ctr) { + retval = -EINVAL; + goto load_unlock_out; + } + if (ctr->load_firmware == NULL) { printk(KERN_DEBUG "kcapi: load: no load functionn"); - capi_ctr_put(ctr); - return -ESRCH; + retval = -ESRCH; + goto load_unlock_out; } if (ldef.t4file.len <= 0) { printk(KERN_DEBUG "kcapi: load: invalid parameter: length of t4file is %d ?n", ldef.t4file.len); - capi_ctr_put(ctr); - return -EINVAL; + retval = -EINVAL; + goto load_unlock_out; } if (ldef.t4file.data == NULL) { printk(KERN_DEBUG "kcapi: load: invalid parameter: dataptr is 0n"); - capi_ctr_put(ctr); - return -EINVAL; + retval = -EINVAL; + goto load_unlock_out; } ldata.firmware.user = 1; @@ -1009,52 +1105,47 @@ static int old_capi_manufacturer(unsigned int cmd, void __user *data) if (ctr->state != CAPI_CTR_DETECTED) { printk(KERN_INFO "kcapi: load: contr=%d not in detect staten", ldef.contr); - capi_ctr_put(ctr); - return -EBUSY; + retval = -EBUSY; + goto load_unlock_out; } ctr->state = CAPI_CTR_LOADING; retval = ctr->load_firmware(ctr, &ldata); - if (retval) { ctr->state = CAPI_CTR_DETECTED; - capi_ctr_put(ctr); - return retval; + goto load_unlock_out; } - while (ctr->state != CAPI_CTR_RUNNING) { + retval = wait_on_ctr_state(ctr, CAPI_CTR_RUNNING); - msleep_interruptible(100); /* 0.1 sec */ - - if (signal_pending(current)) { - capi_ctr_put(ctr); - return -EINTR; - } - } - capi_ctr_put(ctr); - return 0; +load_unlock_out: + mutex_unlock(&capi_controller_lock); + return retval; case AVMB1_RESETCARD: if (copy_from_user(&rdef, data, sizeof(avmb1_resetdef))) return -EFAULT; + + retval = 0; + + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(rdef.contr); - if (!ctr) - return -ESRCH; + if (!ctr) { + retval = -ESRCH; + goto reset_unlock_out; + } if (ctr->state == CAPI_CTR_DETECTED) - return 0; + goto reset_unlock_out; ctr->reset_ctr(ctr); - while (ctr->state > CAPI_CTR_DETECTED) { - - msleep_interruptible(100); /* 0.1 sec */ - - if (signal_pending(current)) - return -EINTR; - } - return 0; + retval = wait_on_ctr_state(ctr, CAPI_CTR_DETECTED); +reset_unlock_out: + mutex_unlock(&capi_controller_lock); + return retval; } return -EINVAL; } @@ -1072,6 +1163,7 @@ static int old_capi_manufacturer(unsigned int cmd, void __user *data) int capi20_manufacturer(unsigned int cmd, void __user *data) { struct capi_ctr *ctr; + int retval; switch (cmd) { #ifdef AVMB1_COMPAT @@ -1089,14 +1181,20 @@ int capi20_manufacturer(unsigned int cmd, void __user *data) if (copy_from_user(&fdef, data, sizeof(kcapi_flagdef))) return -EFAULT; + mutex_lock(&capi_controller_lock); + ctr = get_capi_ctr_by_nr(fdef.contr); - if (!ctr) - return -ESRCH; + if (ctr) { + ctr->traceflag = fdef.flag; + printk(KERN_INFO "kcapi: contr [%03d] set trace=%dn", + ctr->cnr, ctr->traceflag); + retval = 0; + } else + retval = -ESRCH; + + mutex_unlock(&capi_controller_lock); - ctr->traceflag = fdef.flag; - printk(KERN_INFO "kcapi: contr [%03d] set trace=%dn", - ctr->cnr, ctr->traceflag); - return 0; + return retval; } case KCAPI_CMD_ADDCARD: { @@ -1104,7 +1202,6 @@ int capi20_manufacturer(unsigned int cmd, void __user *data) struct capi_driver *driver = NULL; capicardparams cparams; kcapi_carddef cdef; - int retval; if ((retval = copy_from_user(&cdef, data, sizeof(cdef)))) return retval; diff --git a/drivers/isdn/capi/kcapi.h b/drivers/isdn/capi/kcapi.h index 07c5850..966c4b2 100644 --- a/drivers/isdn/capi/kcapi.h +++ b/drivers/isdn/capi/kcapi.h @@ -32,8 +32,10 @@ enum { extern struct list_head capi_drivers; extern struct mutex capi_drivers_lock; -extern struct capi20_appl *capi_applications[CAPI_MAXAPPL]; extern struct capi_ctr *capi_controller[CAPI_MAXCONTR]; +extern struct mutex capi_controller_lock; + +extern struct capi20_appl *capi_applications[CAPI_MAXAPPL]; #ifdef CONFIG_PROC_FS diff --git a/drivers/isdn/capi/kcapi_proc.c b/drivers/isdn/capi/kcapi_proc.c index 71b0761..3e6e17a 100644 --- a/drivers/isdn/capi/kcapi_proc.c +++ b/drivers/isdn/capi/kcapi_proc.c @@ -35,7 +35,10 @@ static char *state2str(unsigned short state) // --------------------------------------------------------------------------- static void *controller_start(struct seq_file *seq, loff_t *pos) + __acquires(capi_controller_lock) { + mutex_lock(&capi_controller_lock); + if (*pos < CAPI_MAXCONTR) return &capi_controller[*pos]; @@ -52,7 +55,9 @@ static void *controller_next(struct seq_file *seq, void *v, loff_t *pos) } static void controller_stop(struct seq_file *seq, void *v) + __releases(capi_controller_lock) { + mutex_unlock(&capi_controller_lock); } static int controller_show(struct seq_file *seq, void *v)