From owner-svn-src-stable@FreeBSD.ORG Mon Oct 19 19:14:04 2009 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B69481065676; Mon, 19 Oct 2009 19:14:04 +0000 (UTC) (envelope-from gallatin@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id A3F3B8FC12; Mon, 19 Oct 2009 19:14:04 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n9JJE4q8010255; Mon, 19 Oct 2009 19:14:04 GMT (envelope-from gallatin@svn.freebsd.org) Received: (from gallatin@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id n9JJE4Cj010251; Mon, 19 Oct 2009 19:14:04 GMT (envelope-from gallatin@svn.freebsd.org) Message-Id: <200910191914.n9JJE4Cj010251@svn.freebsd.org> From: Andrew Gallatin Date: Mon, 19 Oct 2009 19:14:04 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-6@freebsd.org X-SVN-Group: stable-6 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r198245 - in stable/6/sys: . conf contrib/pf dev/cxgb kern sys X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Oct 2009 19:14:04 -0000 Author: gallatin Date: Mon Oct 19 19:14:04 2009 New Revision: 198245 URL: http://svn.freebsd.org/changeset/base/198245 Log: MFC of 178042 to allow safe firmware(9) loading from NIC watchdog handlers. Also MFCed are the related changes 178016, 183614 and 184842. 178042: Do firmare image loading in a context known to have a root directory 183614: Dynamically allocate the task struct in firmware mountroot 184842: Avoid scheduling firmware taskqueues when cold 178016: Add a mountroot event handler. Removal of SI_SUB_MOUNT_ROOT was not merged. 178042 is dependant upon this. This fixes a panic in at least mxge(4) if the NIC has a hardware fault when the firmware image is not resident. Reviewed by: jhb Modified: stable/6/sys/ (props changed) stable/6/sys/conf/ (props changed) stable/6/sys/contrib/pf/ (props changed) stable/6/sys/dev/cxgb/ (props changed) stable/6/sys/kern/subr_firmware.c stable/6/sys/kern/vfs_mount.c stable/6/sys/sys/eventhandler.h Modified: stable/6/sys/kern/subr_firmware.c ============================================================================== --- stable/6/sys/kern/subr_firmware.c Mon Oct 19 19:11:00 2009 (r198244) +++ stable/6/sys/kern/subr_firmware.c Mon Oct 19 19:14:04 2009 (r198245) @@ -1,5 +1,5 @@ /*- - * Copyright (c) 2005, Sam Leffler + * Copyright (c) 2005-2008, Sam Leffler * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -40,6 +40,10 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include + +#include +#include /* * Loadable firmware support. See sys/sys/firmware.h and firmware(9) @@ -88,7 +92,7 @@ struct priv_fw { /* * 'file' is private info managed by the autoload/unload code. * Set at the end of firmware_get(), cleared only in the - * firmware_task, so the latter can depend on its value even + * firmware_unload_task, so the latter can depend on its value even * while the lock is not held. */ linker_file_t file; /* module file, if autoloaded */ @@ -120,14 +124,16 @@ struct priv_fw { static struct priv_fw firmware_table[FIRMWARE_MAX]; /* - * module release are handled in a separate task as they might sleep. + * Firmware module operations are handled in a separate task as they + * might sleep and they require directory context to do i/o. */ -struct task firmware_task; +static struct taskqueue *firmware_tq; +static struct task firmware_unload_task; /* * This mutex protects accesses to the firmware table. */ -struct mtx firmware_mtx; +static struct mtx firmware_mtx; MTX_SYSINIT(firmware, &firmware_mtx, "firmware table", MTX_DEF); /* @@ -226,7 +232,7 @@ firmware_unregister(const char *imagenam } else if (fp->refcnt != 0) { /* cannot unregister */ err = EBUSY; } else { - linker_file_t x = fp->file; /* save value */ + linker_file_t x = fp->file; /* save value */ if (fp->parent != NULL) /* release parent reference */ fp->parent->refcnt--; @@ -243,6 +249,47 @@ firmware_unregister(const char *imagenam return err; } +static void +loadimage(void *arg, int npending) +{ + struct thread *td = curthread; + char *imagename = arg; + struct priv_fw *fp; + linker_file_t result; + int error; + + /* synchronize with the thread that dispatched us */ + mtx_lock(&firmware_mtx); + mtx_unlock(&firmware_mtx); + + if (td->td_proc->p_fd->fd_rdir == NULL) { + printf("%s: root not mounted yet, no way to load image\n", + imagename); + goto done; + } + error = linker_reference_module(imagename, NULL, &result); + if (error != 0) { + printf("%s: could not load firmware image, error %d\n", + imagename, error); + goto done; + } + + mtx_lock(&firmware_mtx); + fp = lookup(imagename, NULL); + if (fp == NULL || fp->file != NULL) { + mtx_unlock(&firmware_mtx); + if (fp == NULL) + printf("%s: firmware image loaded, " + "but did not register\n", imagename); + (void) linker_release_module(imagename, NULL, NULL); + goto done; + } + fp->file = result; /* record the module identity */ + mtx_unlock(&firmware_mtx); +done: + wakeup_one(imagename); /* we're done */ +} + /* * Lookup and potentially load the specified firmware image. * If the firmware is not found in the registry, try to load a kernel @@ -253,9 +300,9 @@ firmware_unregister(const char *imagenam const struct firmware * firmware_get(const char *imagename) { + struct task fwload_task; struct thread *td; struct priv_fw *fp; - linker_file_t result; mtx_lock(&firmware_mtx); fp = lookup(imagename, NULL); @@ -264,29 +311,34 @@ firmware_get(const char *imagename) /* * Image not present, try to load the module holding it. */ - mtx_unlock(&firmware_mtx); td = curthread; if (suser(td) != 0 || securelevel_gt(td->td_ucred, 0) != 0) { + mtx_unlock(&firmware_mtx); printf("%s: insufficient privileges to " "load firmware image %s\n", __func__, imagename); return NULL; } - (void) linker_reference_module(imagename, NULL, &result); + /* + * Defer load to a thread with known context. linker_reference_module + * may do filesystem i/o which requires root & current dirs, etc. + * Also we must not hold any mtx's over this call which is problematic. + */ + if (!cold) { + TASK_INIT(&fwload_task, 0, loadimage, __DECONST(void *, + imagename)); + taskqueue_enqueue(firmware_tq, &fwload_task); + msleep(__DECONST(void *, imagename), &firmware_mtx, 0, + "fwload", 0); + } /* - * After loading the module, see if the image is registered now. + * After attempting to load the module, see if the image is registered. */ - mtx_lock(&firmware_mtx); fp = lookup(imagename, NULL); if (fp == NULL) { mtx_unlock(&firmware_mtx); - printf("%s: failed to load firmware image %s\n", - __func__, imagename); - (void) linker_release_module(imagename, NULL, NULL); return NULL; } - fp->file = result; /* record the module identity */ - found: /* common exit point on success */ fp->refcnt++; mtx_unlock(&firmware_mtx); @@ -299,8 +351,8 @@ found: /* common exit point on succes * to release the resource, but the flag is only advisory. * * If this is the last reference to the firmware image, and this is an - * autoloaded module, wake up the firmware_task to figure out what to do - * with the associated module. + * autoloaded module, wake up the firmware_unload_task to figure out + * what to do with the associated module. */ void firmware_put(const struct firmware *p, int flags) @@ -313,12 +365,62 @@ firmware_put(const struct firmware *p, i if (flags & FIRMWARE_UNLOAD) fp->flags |= FW_UNLOAD; if (fp->file) - taskqueue_enqueue(taskqueue_thread, &firmware_task); + taskqueue_enqueue(firmware_tq, &firmware_unload_task); } mtx_unlock(&firmware_mtx); } /* + * Setup directory state for the firmware_tq thread so we can do i/o. + */ +static void +set_rootvnode(void *arg, int npending) +{ + struct thread *td = curthread; + struct proc *p = td->td_proc; + + FILEDESC_LOCK(p->p_fd); + if (p->p_fd->fd_cdir == NULL) { + p->p_fd->fd_cdir = rootvnode; + VREF(rootvnode); + } + if (p->p_fd->fd_rdir == NULL) { + p->p_fd->fd_rdir = rootvnode; + VREF(rootvnode); + } + FILEDESC_UNLOCK(p->p_fd); + + free(arg, M_TEMP); +} + +/* + * Event handler called on mounting of /; bounce a task + * into the task queue thread to setup it's directories. + */ +static void +firmware_mountroot(void *arg) +{ + struct task *setroot_task; + + setroot_task = malloc(sizeof(struct task), M_TEMP, M_NOWAIT); + if (setroot_task != NULL) { + TASK_INIT(setroot_task, 0, set_rootvnode, setroot_task); + taskqueue_enqueue(firmware_tq, setroot_task); + } else + printf("%s: no memory for task!\n", __func__); +} + +static eventhandler_tag mountroot_tag; +static void +mountroot_evh_init(void *ctx) +{ + mountroot_tag = EVENTHANDLER_REGISTER(mountroot, + firmware_mountroot, ctx, 0); +} +SYSINIT(mountroot_evh_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, + mountroot_evh_init, NULL); + +/* * The body of the task in charge of unloading autoloaded modules * that are not needed anymore. * Images can be cross-linked so we may need to make multiple passes, @@ -382,11 +484,23 @@ static int firmware_modevent(module_t mod, int type, void *unused) { struct priv_fw *fp; - int i, err = EINVAL; + int i, err; switch (type) { case MOD_LOAD: - TASK_INIT(&firmware_task, 0, unloadentry, NULL); + TASK_INIT(&firmware_unload_task, 0, unloadentry, NULL); + firmware_tq = taskqueue_create("taskqueue_firmware", M_WAITOK, + taskqueue_thread_enqueue, &firmware_tq, NULL); + /* NB: use our own loop routine that sets up context */ + (void) taskqueue_start_threads(&firmware_tq, 1, PWAIT, + "firmware taskq"); + if (rootvnode != NULL) { + /* + * Root is already mounted so we won't get an event; + * simulate one here. + */ + firmware_mountroot(NULL); + } return 0; case MOD_UNLOAD: @@ -397,8 +511,9 @@ firmware_modevent(module_t mod, int type fp->flags |= FW_UNLOAD;; } mtx_unlock(&firmware_mtx); - taskqueue_enqueue(taskqueue_thread, &firmware_task); - taskqueue_drain(taskqueue_thread, &firmware_task); + taskqueue_enqueue(firmware_tq, &firmware_unload_task); + taskqueue_drain(firmware_tq, &firmware_unload_task); + err = 0; for (i = 0; i < FIRMWARE_MAX; i++) { fp = &firmware_table[i]; if (fp->fw.name != NULL) { @@ -408,6 +523,8 @@ firmware_modevent(module_t mod, int type err = EINVAL; } } + if (err == 0) + taskqueue_free(firmware_tq); return err; } return EINVAL; Modified: stable/6/sys/kern/vfs_mount.c ============================================================================== --- stable/6/sys/kern/vfs_mount.c Mon Oct 19 19:11:00 2009 (r198244) +++ stable/6/sys/kern/vfs_mount.c Mon Oct 19 19:14:04 2009 (r198245) @@ -1360,6 +1360,8 @@ set_rootvnode(struct thread *td) FILEDESC_UNLOCK(p->p_fd); VOP_UNLOCK(rootvnode, 0, td); + + EVENTHANDLER_INVOKE(mountroot); } /* Modified: stable/6/sys/sys/eventhandler.h ============================================================================== --- stable/6/sys/sys/eventhandler.h Mon Oct 19 19:11:00 2009 (r198244) +++ stable/6/sys/sys/eventhandler.h Mon Oct 19 19:14:04 2009 (r198245) @@ -156,6 +156,10 @@ typedef void (*vm_lowmem_handler_t)(void #define LOWMEM_PRI_DEFAULT EVENTHANDLER_PRI_FIRST EVENTHANDLER_DECLARE(vm_lowmem, vm_lowmem_handler_t); +/* Root mounted event */ +typedef void (*mountroot_handler_t)(void *); +EVENTHANDLER_DECLARE(mountroot, mountroot_handler_t); + /* * Process events * process_fork and exit handlers are called without Giant.