> -----Original Message-----
> From: Guo, Jia
> Sent: Friday, April 6, 2018 11:57 AM
> To: step...@networkplumber.org; Richardson, Bruce
> <bruce.richard...@intel.com>; Yigit, Ferruh <ferruh.yi...@intel.com>; Ananyev,
> Konstantin <konstantin.anan...@intel.com>; gaetan.ri...@6wind.com; Wu,
> Jingjing <jingjing...@intel.com>; tho...@monjalon.net;
> mo...@mellanox.com; Van Haaren, Harry <harry.van.haa...@intel.com>; Tan,
> Jianfeng <jianfeng....@intel.com>
> Cc: jblu...@infradead.org; shreyansh.j...@nxp.com; dev@dpdk.org; Guo, Jia
> <jia....@intel.com>; Zhang, Helin <helin.zh...@intel.com>
> Subject: [PATCH V19 1/4] bus/pci: introduce device hot unplug handle
>
> As of device hot unplug, we need some preparatory measures so that we will
> not encounter memory fault after device be plug out of the system,
> and also let we could recover the running data path but not been break.
> This allows the buses to handle device hot unplug event.
> The patch only enable the ops in pci bus, when handle device hot unplug
> event, remap a dummy memory to avoid bus read/write error.
> Other buses could accordingly implement this ops specific by themselves.
>
> Signed-off-by: Jeff Guo <jia....@intel.com>
> ---
> v19->v18:
> fix some typo and squeeze patch
> ---
> drivers/bus/pci/pci_common.c | 42
> +++++++++++++++++++++++++++++++++
> drivers/bus/pci/pci_common_uio.c | 32 +++++++++++++++++++++++++
> drivers/bus/pci/private.h | 12 ++++++++++
> lib/librte_eal/common/include/rte_bus.h | 15 ++++++++++++
> 4 files changed, 101 insertions(+)
>
> diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c
> index 2a00f36..09192ed 100644
> --- a/drivers/bus/pci/pci_common.c
> +++ b/drivers/bus/pci/pci_common.c
> @@ -474,6 +474,47 @@ pci_find_device(const struct rte_device *start,
> rte_dev_cmp_t cmp,
> }
>
> static int
> +pci_handle_hot_unplug(struct rte_device *dev)
> +{
> + struct rte_pci_device *pdev;
> + int ret;
> +
> + if (dev == NULL)
> + return -EINVAL;
> +
> + pdev = RTE_DEV_TO_PCI(dev);
> +
> + /* remap resources for devices */
> + switch (pdev->kdrv) {
> + case RTE_KDRV_VFIO:
> +#ifdef VFIO_PRESENT
> + /* TODO */
> +#endif
> + break;
> + case RTE_KDRV_IGB_UIO:
> + case RTE_KDRV_UIO_GENERIC:
> + if (rte_eal_using_phys_addrs()) {
> + /* map resources for devices that use uio */
> + ret = pci_uio_remap_resource(pdev);
> + }
> + break;
> + case RTE_KDRV_NIC_UIO:
> + ret = pci_uio_remap_resource(pdev);
> + break;
> + default:
> + RTE_LOG(DEBUG, EAL,
> + " Not managed by a supported kernel driver,
> skipped\n");
> + ret = -1;
> + break;
> + }
> +
> + if (ret != 0)
> + RTE_LOG(ERR, EAL, "failed to handle hot unplug of %s",
> + pdev->name);
> + return ret;
> +}
> +
> +static int
> pci_plug(struct rte_device *dev)
> {
> return pci_probe_all_drivers(RTE_DEV_TO_PCI(dev));
> @@ -503,6 +544,7 @@ struct rte_pci_bus rte_pci_bus = {
> .unplug = pci_unplug,
> .parse = pci_parse,
> .get_iommu_class = rte_pci_get_iommu_class,
> + .handle_hot_unplug = pci_handle_hot_unplug,
> },
> .device_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.device_list),
> .driver_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.driver_list),
> diff --git a/drivers/bus/pci/pci_common_uio.c
> b/drivers/bus/pci/pci_common_uio.c
> index 54bc20b..31a4094 100644
> --- a/drivers/bus/pci/pci_common_uio.c
> +++ b/drivers/bus/pci/pci_common_uio.c
> @@ -146,6 +146,38 @@ pci_uio_unmap(struct mapped_pci_resource *uio_res)
> }
> }
>
> +/* remap the PCI resource of a PCI device in private virtual memory */
> +int
> +pci_uio_remap_resource(struct rte_pci_device *dev)
> +{
> + int i;
> + void *map_address;
> +
> + if (dev == NULL)
> + return -1;
> +
> + /* Remap all BARs */
> + for (i = 0; i != PCI_MAX_RESOURCE; i++) {
> + /* skip empty BAR */
> + if (dev->mem_resource[i].phys_addr == 0)
> + continue;
> + pci_unmap_resource(dev->mem_resource[i].addr,
> + (size_t)dev->mem_resource[i].len);
> + map_address = pci_map_resource(
> + dev->mem_resource[i].addr, -1, 0,
> + (size_t)dev->mem_resource[i].len,
> + MAP_ANONYMOUS | MAP_FIXED);
Wouldn't it be possible to use mremap() here?
To do munmap/mmap in one go?
> + if (map_address == MAP_FAILED) {
> + RTE_LOG(ERR, EAL,
> + "Cannot remap resource for device %s\n",
> + dev->name);
> + return -1;
> + }
> + }
> +
> + return 0;
> +}
> +
