From patchwork Tue May 10 16:02:27 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 774692 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p4AG3MTr023069 for ; Tue, 10 May 2011 16:03:23 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932940Ab1EJQCd (ORCPT ); Tue, 10 May 2011 12:02:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:64768 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932902Ab1EJQCa (ORCPT ); Tue, 10 May 2011 12:02:30 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p4AG2Stg020712 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 10 May 2011 12:02:28 -0400 Received: from s20.home (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p4AG2RqL015415; Tue, 10 May 2011 12:02:28 -0400 From: Alex Williamson Subject: [PATCH v4 2/3] PCI: Add interfaces to store and load the device saved state To: linux-pci@vger.kernel.org, jbarnes@virtuousgeek.org Cc: alex.williamson@redhat.com, kvm@vger.kernel.org, avi@redhat.com, linux-kernel@vger.kernel.org, jan.kiszka@siemens.com Date: Tue, 10 May 2011 10:02:27 -0600 Message-ID: <20110510160217.3490.84987.stgit@s20.home> In-Reply-To: <20110510155642.3490.61935.stgit@s20.home> References: <20110510155642.3490.61935.stgit@s20.home> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Tue, 10 May 2011 16:03:23 +0000 (UTC) For KVM device assignment, we'd like to save off the state of a device prior to passing it to the guest and restore it later. We also want to allow pci_reset_funciton() to be called while the device is owned by the guest. This however overwrites and invalidates the struct pci_dev buffers, so we can't just manually call save and restore. Add generic interfaces for the saved state to be stored and reloaded back into struct pci_dev at a later time. Signed-off-by: Alex Williamson --- drivers/pci/pci.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 4 ++ 2 files changed, 102 insertions(+), 0 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 416930a..be423a6 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -976,6 +976,104 @@ void pci_restore_state(struct pci_dev *dev) dev->state_saved = false; } +struct pci_saved_state { + u32 config_space[16]; + struct pci_cap_saved_data cap[0]; +}; + +/** + * pci_store_saved_state - Allocate and return an opaque struct containing + * the device saved state. + * @dev: PCI device that we're dealing with + * + * Rerturn NULL if no state or error. + */ +struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev) +{ + struct pci_saved_state *state; + struct pci_cap_saved_state *tmp; + struct pci_cap_saved_data *cap; + struct hlist_node *pos; + size_t size; + + if (!dev->state_saved) + return NULL; + + size = sizeof(*state) + sizeof(struct pci_cap_saved_data); + + hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next) + size += sizeof(struct pci_cap_saved_data) + tmp->cap.size; + + state = kzalloc(size, GFP_KERNEL); + if (!state) + return NULL; + + memcpy(state->config_space, dev->saved_config_space, + sizeof(state->config_space)); + + cap = state->cap; + hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next) { + size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size; + memcpy(cap, &tmp->cap, len); + cap = (struct pci_cap_saved_data *)((u8 *)cap + len); + } + /* Empty cap_save terminates list */ + + return state; +} +EXPORT_SYMBOL_GPL(pci_store_saved_state); + +/** + * pci_load_saved_state - Reload the provided save state into struct pci_dev. + * @dev: PCI device that we're dealing with + * @state: Saved state returned from pci_store_saved_state() + */ +int pci_load_saved_state(struct pci_dev *dev, struct pci_saved_state *state) +{ + struct pci_cap_saved_data *cap; + + dev->state_saved = false; + + if (!state) + return 0; + + memcpy(dev->saved_config_space, state->config_space, + sizeof(state->config_space)); + + cap = state->cap; + while (cap->size) { + struct pci_cap_saved_state *tmp; + + tmp = pci_find_saved_cap(dev, cap->cap_nr); + if (!tmp || tmp->cap.size != cap->size) + return -EINVAL; + + memcpy(tmp->cap.data, cap->data, tmp->cap.size); + cap = (struct pci_cap_saved_data *)((u8 *)cap + + sizeof(struct pci_cap_saved_data) + cap->size); + } + + dev->state_saved = true; + return 0; +} +EXPORT_SYMBOL_GPL(pci_load_saved_state); + +/** + * pci_load_and_free_saved_state - Reload the save state pointed to by state, + * and free the memory allocated for it. + * @dev: PCI device that we're dealing with + * @state: Pointer to saved state returned from pci_store_saved_state() + */ +int pci_load_and_free_saved_state(struct pci_dev *dev, + struct pci_saved_state **state) +{ + int ret = pci_load_saved_state(dev, *state); + kfree(*state); + *state = NULL; + return ret; +} +EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state); + static int do_pci_enable_device(struct pci_dev *dev, int bars) { int err; diff --git a/include/linux/pci.h b/include/linux/pci.h index 4dcb429..5457d99 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -812,6 +812,10 @@ size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, size_t size); /* Power management related routines */ int pci_save_state(struct pci_dev *dev); void pci_restore_state(struct pci_dev *dev); +struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev); +int pci_load_saved_state(struct pci_dev *dev, struct pci_saved_state *state); +int pci_load_and_free_saved_state(struct pci_dev *dev, + struct pci_saved_state **state); int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state); int pci_set_power_state(struct pci_dev *dev, pci_power_t state); pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state);