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[73.243.191.173]) by smtp.gmail.com with ESMTPSA id s5sm16471411iol.88.2019.09.03.21.39.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Sep 2019 21:39:51 -0700 (PDT) From: Kelsey Skunberg To: bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org, skunberg.kelsey@gmail.com Cc: skhan@linuxfoundation.org, rafael.j.wysocki@intel.com, keith.busch@intel.com Subject: [PATCH 1/2] PCI: Change pci_device_is_present() to pci_dev_is_inaccessible() Date: Tue, 3 Sep 2019 22:36:34 -0600 Message-Id: <20190904043633.65026-2-skunberg.kelsey@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190904043633.65026-1-skunberg.kelsey@gmail.com> References: <20190904043633.65026-1-skunberg.kelsey@gmail.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The pci_device_is_present() name may encourage poor practice of calling pci_device_is_present() and if true, assuming the device is still present after the call. This type of practice can be racy when assuming a device is still connected after checking. Change pci_device_is_present() to pci_dev_is_inaccessible() to promote only using to learn whether we should avoid accessing a device that's inaccessible. Change pci_device_is_inaccessible() to now return true if PCI device is inaccessible. Change the boolean values returned from calling pci_dev_is_inaccessible() to their opposite value to reflect the change of checking if the device is present to checking if the device is inaccessible. Example: Before: if (!pci_device_is_present(tp->pdev)) return -ENODEV; After: if (pci_dev_is_inaccessible(tp->pdev)) return -ENODEV; Signed-off-by: Kelsey Skunberg --- drivers/net/ethernet/broadcom/tg3.c | 4 ++-- drivers/net/ethernet/intel/igb/igb_main.c | 2 +- drivers/nvme/host/pci.c | 2 +- drivers/pci/hotplug/acpiphp_glue.c | 2 +- drivers/pci/pci.c | 10 +++++----- drivers/thunderbolt/nhi.c | 2 +- include/linux/pci.h | 2 +- 7 files changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index 4c404d2213f9..7646a8303d01 100644 --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c @@ -9067,7 +9067,7 @@ static int tg3_chip_reset(struct tg3 *tp) void (*write_op)(struct tg3 *, u32, u32); int i, err; - if (!pci_device_is_present(tp->pdev)) + if (pci_dev_is_inaccessible(tp->pdev)) return -ENODEV; tg3_nvram_lock(tp); @@ -11782,7 +11782,7 @@ static int tg3_close(struct net_device *dev) tg3_stop(tp); - if (pci_device_is_present(tp->pdev)) { + if (!pci_dev_is_inaccessible(tp->pdev)) { tg3_power_down_prepare(tp); tg3_carrier_off(tp); diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index b4df3e319467..87bc067c2abc 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -8835,7 +8835,7 @@ static int __maybe_unused igb_resume(struct device *dev) pci_restore_state(pdev); pci_save_state(pdev); - if (!pci_device_is_present(pdev)) + if (pci_dev_is_inaccessible(pdev)) return -ENODEV; err = pci_enable_device_mem(pdev); if (err) { diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index bb970ca82517..2a4500325471 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2812,7 +2812,7 @@ static void nvme_remove(struct pci_dev *pdev) nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING); pci_set_drvdata(pdev, NULL); - if (!pci_device_is_present(pdev)) { + if (pci_dev_is_inaccessible(pdev)) { nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD); nvme_dev_disable(dev, true); nvme_dev_remove_admin(dev); diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index e4c46637f32f..9cc2d65877bd 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -647,7 +647,7 @@ static void trim_stale_devices(struct pci_dev *dev) alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta)); } if (!alive) - alive = pci_device_is_present(dev); + alive = !pci_dev_is_inaccessible(dev); if (!alive) { pci_dev_set_disconnected(dev, NULL); diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 29ed5ec1ac27..7b4e248db5f9 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -931,7 +931,7 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state) void pci_update_current_state(struct pci_dev *dev, pci_power_t state) { if (platform_pci_get_power_state(dev) == PCI_D3cold || - !pci_device_is_present(dev)) { + pci_dev_is_inaccessible(dev)) { dev->current_state = PCI_D3cold; } else if (dev->pm_cap) { u16 pmcsr; @@ -5906,15 +5906,15 @@ bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2) test_bit(dev1->devfn, dev2->dma_alias_mask)); } -bool pci_device_is_present(struct pci_dev *pdev) +bool pci_dev_is_inaccessible(struct pci_dev *pdev) { u32 v; if (pci_dev_is_disconnected(pdev)) - return false; - return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0); + return true; + return !pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0); } -EXPORT_SYMBOL_GPL(pci_device_is_present); +EXPORT_SYMBOL_GPL(pci_dev_is_inaccessible); void pci_ignore_hotplug(struct pci_dev *dev) { diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c index 27fbe62c7ddd..597c7579d882 100644 --- a/drivers/thunderbolt/nhi.c +++ b/drivers/thunderbolt/nhi.c @@ -879,7 +879,7 @@ static int nhi_resume_noirq(struct device *dev) * unplugged last device which causes the host controller to go * away on PCs. */ - if (!pci_device_is_present(pdev)) + if (pci_dev_is_inaccessible(pdev)) tb->nhi->going_away = true; else nhi_enable_int_throttling(tb->nhi); diff --git a/include/linux/pci.h b/include/linux/pci.h index 9e700d9f9f28..e599068537cf 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1202,7 +1202,7 @@ int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size void pci_release_resource(struct pci_dev *dev, int resno); int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size); int pci_select_bars(struct pci_dev *dev, unsigned long flags); -bool pci_device_is_present(struct pci_dev *pdev); +bool pci_dev_is_inaccessible(struct pci_dev *pdev); void pci_ignore_hotplug(struct pci_dev *dev); int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr,