diff options
author | 2021-01-04 14:55:00 +0800 | |
---|---|---|
committer | 2021-02-23 07:52:58 -0500 | |
commit | fd502729fbbf6a76fdb7acae4506486bfbb7c4f6 (patch) | |
tree | 72fe5de3d38f2a2474fcdeed8c02552881f97d90 /drivers/virtio | |
parent | virito-pci-modern: rename map_capability() to vp_modern_map_capability() (diff) | |
download | linux-fd502729fbbf6a76fdb7acae4506486bfbb7c4f6.tar.gz linux-fd502729fbbf6a76fdb7acae4506486bfbb7c4f6.tar.bz2 linux-fd502729fbbf6a76fdb7acae4506486bfbb7c4f6.zip |
virtio-pci: introduce modern device module
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210104065503.199631-17-jasowang@redhat.com
Including a bugfix:
virtio: don't prompt CONFIG_VIRTIO_PCI_MODERN
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 86b87c9d858b6 ("virtio-pci: introduce modern device module")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210223061905.422659-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/virtio')
-rw-r--r-- | drivers/virtio/Kconfig | 9 | ||||
-rw-r--r-- | drivers/virtio/Makefile | 1 | ||||
-rw-r--r-- | drivers/virtio/virtio_pci_common.h | 27 | ||||
-rw-r--r-- | drivers/virtio/virtio_pci_modern.c | 617 | ||||
-rw-r--r-- | drivers/virtio/virtio_pci_modern_dev.c | 599 |
5 files changed, 610 insertions, 643 deletions
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 7b41130d3f35..ce1b3f6ec325 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -12,6 +12,14 @@ config ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS This option is selected if the architecture may need to enforce VIRTIO_F_ACCESS_PLATFORM +config VIRTIO_PCI_LIB + tristate + help + Modern PCI device implementation. This module implements the + basic probe and control for devices which are based on modern + PCI device with possible vendor specific extensions. Any + module that selects this module must depend on PCI. + menuconfig VIRTIO_MENU bool "Virtio drivers" default y @@ -21,6 +29,7 @@ if VIRTIO_MENU config VIRTIO_PCI tristate "PCI driver for virtio devices" depends on PCI + select VIRTIO_PCI_LIB select VIRTIO help This driver provides support for virtio based paravirtual device diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 591e6f72aa54..699bbea0465f 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o +obj-$(CONFIG_VIRTIO_PCI_LIB) += virtio_pci_modern_dev.o obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index f35ff5b6b467..beec047a8f8d 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -25,6 +25,7 @@ #include <linux/virtio_config.h> #include <linux/virtio_ring.h> #include <linux/virtio_pci.h> +#include <linux/virtio_pci_modern.h> #include <linux/highmem.h> #include <linux/spinlock.h> @@ -39,32 +40,6 @@ struct virtio_pci_vq_info { unsigned msix_vector; }; -struct virtio_pci_modern_device { - struct pci_dev *pci_dev; - - struct virtio_pci_common_cfg __iomem *common; - /* Device-specific data (non-legacy mode) */ - void __iomem *device; - /* Base of vq notifications (non-legacy mode). */ - void __iomem *notify_base; - /* Where to read and clear interrupt */ - u8 __iomem *isr; - - /* So we can sanity-check accesses. */ - size_t notify_len; - size_t device_len; - - /* Capability for when we need to map notifications per-vq. */ - int notify_map_cap; - - /* Multiply queue_notify_off by this value. (non-legacy mode). */ - u32 notify_offset_multiplier; - - int modern_bars; - - struct virtio_device_id id; -}; - /* Our device structure */ struct virtio_pci_device { struct virtio_device vdev; diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index a5e3a5e40323..fbd4ebc00eb6 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -19,158 +19,6 @@ #define VIRTIO_RING_NO_LEGACY #include "virtio_pci_common.h" -/* - * Type-safe wrappers for io accesses. - * Use these to enforce at compile time the following spec requirement: - * - * The driver MUST access each field using the “natural” access - * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses - * for 16-bit fields and 8-bit accesses for 8-bit fields. - */ -static inline u8 vp_ioread8(const u8 __iomem *addr) -{ - return ioread8(addr); -} -static inline u16 vp_ioread16 (const __le16 __iomem *addr) -{ - return ioread16(addr); -} - -static inline u32 vp_ioread32(const __le32 __iomem *addr) -{ - return ioread32(addr); -} - -static inline void vp_iowrite8(u8 value, u8 __iomem *addr) -{ - iowrite8(value, addr); -} - -static inline void vp_iowrite16(u16 value, __le16 __iomem *addr) -{ - iowrite16(value, addr); -} - -static inline void vp_iowrite32(u32 value, __le32 __iomem *addr) -{ - iowrite32(value, addr); -} - -static void vp_iowrite64_twopart(u64 val, - __le32 __iomem *lo, __le32 __iomem *hi) -{ - vp_iowrite32((u32)val, lo); - vp_iowrite32(val >> 32, hi); -} - -/* - * vp_modern_map_capability - map a part of virtio pci capability - * @mdev: the modern virtio-pci device - * @off: offset of the capability - * @minlen: minimal length of the capability - * @align: align requirement - * @start: start from the capability - * @size: map size - * @len: the length that is actually mapped - * - * Returns the io address of for the part of the capability - */ -void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off, - size_t minlen, - u32 align, - u32 start, u32 size, - size_t *len) -{ - struct pci_dev *dev = mdev->pci_dev; - u8 bar; - u32 offset, length; - void __iomem *p; - - pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, - bar), - &bar); - pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), - &offset); - pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), - &length); - - if (length <= start) { - dev_err(&dev->dev, - "virtio_pci: bad capability len %u (>%u expected)\n", - length, start); - return NULL; - } - - if (length - start < minlen) { - dev_err(&dev->dev, - "virtio_pci: bad capability len %u (>=%zu expected)\n", - length, minlen); - return NULL; - } - - length -= start; - - if (start + offset < offset) { - dev_err(&dev->dev, - "virtio_pci: map wrap-around %u+%u\n", - start, offset); - return NULL; - } - - offset += start; - - if (offset & (align - 1)) { - dev_err(&dev->dev, - "virtio_pci: offset %u not aligned to %u\n", - offset, align); - return NULL; - } - - if (length > size) - length = size; - - if (len) - *len = length; - - if (minlen + offset < minlen || - minlen + offset > pci_resource_len(dev, bar)) { - dev_err(&dev->dev, - "virtio_pci: map virtio %zu@%u " - "out of range on bar %i length %lu\n", - minlen, offset, - bar, (unsigned long)pci_resource_len(dev, bar)); - return NULL; - } - - p = pci_iomap_range(dev, bar, offset, length); - if (!p) - dev_err(&dev->dev, - "virtio_pci: unable to map virtio %u@%u on bar %i\n", - length, offset, bar); - return p; -} - -/* - * vp_modern_get_features - get features from device - * @mdev: the modern virtio-pci device - * - * Returns the features read from the device - */ -static u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - u64 features; - - vp_iowrite32(0, &cfg->device_feature_select); - features = vp_ioread32(&cfg->device_feature); - vp_iowrite32(1, &cfg->device_feature_select); - features |= ((u64)vp_ioread32(&cfg->device_feature) << 32); - - return features; -} - -/* virtio config->get_features() implementation */ static u64 vp_get_features(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -188,149 +36,6 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); } -/* - * vp_modern_set_features - set features to device - * @mdev: the modern virtio-pci device - * @features: the features set to device - */ -static void vp_modern_set_features(struct virtio_pci_modern_device *mdev, - u64 features) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - vp_iowrite32(0, &cfg->guest_feature_select); - vp_iowrite32((u32)features, &cfg->guest_feature); - vp_iowrite32(1, &cfg->guest_feature_select); - vp_iowrite32(features >> 32, &cfg->guest_feature); -} - -/* - * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue - * @mdev: the modern virtio-pci device - * @index: queue index - * @vector: the config vector - * - * Returns the config vector read from the device - */ -static u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev, - u16 index, u16 vector) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - vp_iowrite16(index, &cfg->queue_select); - vp_iowrite16(vector, &cfg->queue_msix_vector); - /* Flush the write out to device */ - return vp_ioread16(&cfg->queue_msix_vector); -} - -/* - * vp_modern_queue_address - set the virtqueue address - * @mdev: the modern virtio-pci device - * @index: the queue index - * @desc_addr: address of the descriptor area - * @driver_addr: address of the driver area - * @device_addr: address of the device area - */ -static void vp_modern_queue_address(struct virtio_pci_modern_device *mdev, - u16 index, u64 desc_addr, u64 driver_addr, - u64 device_addr) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - vp_iowrite16(index, &cfg->queue_select); - - vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo, - &cfg->queue_desc_hi); - vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo, - &cfg->queue_avail_hi); - vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo, - &cfg->queue_used_hi); -} - -/* - * vp_modern_set_queue_enable - enable a virtqueue - * @mdev: the modern virtio-pci device - * @index: the queue index - * @enable: whether the virtqueue is enable or not - */ -static void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev, - u16 index, bool enable) -{ - vp_iowrite16(index, &mdev->common->queue_select); - vp_iowrite16(enable, &mdev->common->queue_enable); -} - -/* - * vp_modern_get_queue_enable - enable a virtqueue - * @mdev: the modern virtio-pci device - * @index: the queue index - * - * Returns whether a virtqueue is enabled or not - */ -static bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev, - u16 index) -{ - vp_iowrite16(index, &mdev->common->queue_select); - - return vp_ioread16(&mdev->common->queue_enable); -} - -/* - * vp_modern_set_queue_size - set size for a virtqueue - * @mdev: the modern virtio-pci device - * @index: the queue index - * @size: the size of the virtqueue - */ -static void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev, - u16 index, u16 size) -{ - vp_iowrite16(index, &mdev->common->queue_select); - vp_iowrite16(size, &mdev->common->queue_size); - -} - -/* - * vp_modern_get_queue_size - get size for a virtqueue - * @mdev: the modern virtio-pci device - * @index: the queue index - * - * Returns the size of the virtqueue - */ -static u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev, - u16 index) -{ - vp_iowrite16(index, &mdev->common->queue_select); - - return vp_ioread16(&mdev->common->queue_size); - -} - -/* - * vp_modern_get_num_queues - get the number of virtqueues - * @mdev: the modern virtio-pci device - * - * Returns the number of virtqueues - */ -static u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev) -{ - return vp_ioread16(&mdev->common->num_queues); -} - -/* - * vp_modern_get_queue_notify_off - get notification offset for a virtqueue - * @mdev: the modern virtio-pci device - * @index: the queue index - * - * Returns the notification offset for a virtqueue - */ -static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev, - u16 index) -{ - vp_iowrite16(index, &mdev->common->queue_select); - - return vp_ioread16(&mdev->common->queue_notify_off); -} - /* virtio config->finalize_features() implementation */ static int vp_finalize_features(struct virtio_device *vdev) { @@ -429,19 +134,6 @@ static void vp_set(struct virtio_device *vdev, unsigned offset, } } -/* - * vp_modern_generation - get the device genreation - * @mdev: the modern virtio-pci device - * - * Returns the genreation read from device - */ -static u32 vp_modern_generation(struct virtio_pci_modern_device *mdev) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - return vp_ioread8(&cfg->config_generation); -} - static u32 vp_generation(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -449,19 +141,6 @@ static u32 vp_generation(struct virtio_device *vdev) return vp_modern_generation(&vp_dev->mdev); } -/* - * vp_modern_get_status - get the device status - * @mdev: the modern virtio-pci device - * - * Returns the status read from device - */ -static u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - return vp_ioread8(&cfg->device_status); -} - /* config->{get,set}_status() implementations */ static u8 vp_get_status(struct virtio_device *vdev) { @@ -470,19 +149,6 @@ static u8 vp_get_status(struct virtio_device *vdev) return vp_modern_get_status(&vp_dev->mdev); } -/* - * vp_modern_set_status - set status to device - * @mdev: the modern virtio-pci device - * @status: the status set to device - */ -static void vp_modern_set_status(struct virtio_pci_modern_device *mdev, - u8 status) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - vp_iowrite8(status, &cfg->device_status); -} - static void vp_set_status(struct virtio_device *vdev, u8 status) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -510,25 +176,6 @@ static void vp_reset(struct virtio_device *vdev) vp_synchronize_vectors(vdev); } -/* - * vp_modern_config_vector - set the vector for config interrupt - * @mdev: the modern virtio-pci device - * @vector: the config vector - * - * Returns the config vector read from the device - */ -static u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev, - u16 vector) -{ - struct virtio_pci_common_cfg __iomem *cfg = mdev->common; - - /* Setup the vector used for configuration events */ - vp_iowrite16(vector, &cfg->msix_config); - /* Verify we had enough resources to assign the vector */ - /* Will also flush the write out to device */ - return vp_ioread16(&cfg->msix_config); -} - static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) { return vp_modern_config_vector(&vp_dev->mdev, vector); @@ -789,253 +436,6 @@ static const struct virtio_config_ops virtio_pci_config_ops = { .get_shm_region = vp_get_shm_region, }; -/** - * virtio_pci_find_capability - walk capabilities to find device info. - * @dev: the pci device - * @cfg_type: the VIRTIO_PCI_CAP_* value we seek - * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. - * @bars: the bitmask of BARs - * - * Returns offset of the capability, or 0. - */ -static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, - u32 ioresource_types, int *bars) -{ - int pos; - - for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); - pos > 0; - pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { - u8 type, bar; - pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, - cfg_type), - &type); - pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, - bar), - &bar); - - /* Ignore structures with reserved BAR values */ - if (bar > 0x5) - continue; - - if (type == cfg_type) { - if (pci_resource_len(dev, bar) && - pci_resource_flags(dev, bar) & ioresource_types) { - *bars |= (1 << bar); - return pos; - } - } - } - return 0; -} - -/* This is part of the ABI. Don't screw with it. */ -static inline void check_offsets(void) -{ - /* Note: disk space was harmed in compilation of this function. */ - BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR != - offsetof(struct virtio_pci_cap, cap_vndr)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT != - offsetof(struct virtio_pci_cap, cap_next)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN != - offsetof(struct virtio_pci_cap, cap_len)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE != - offsetof(struct virtio_pci_cap, cfg_type)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR != - offsetof(struct virtio_pci_cap, bar)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET != - offsetof(struct virtio_pci_cap, offset)); - BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH != - offsetof(struct virtio_pci_cap, length)); - BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT != - offsetof(struct virtio_pci_notify_cap, - notify_off_multiplier)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT != - offsetof(struct virtio_pci_common_cfg, - device_feature_select)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF != - offsetof(struct virtio_pci_common_cfg, device_feature)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT != - offsetof(struct virtio_pci_common_cfg, - guest_feature_select)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF != - offsetof(struct virtio_pci_common_cfg, guest_feature)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX != - offsetof(struct virtio_pci_common_cfg, msix_config)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ != - offsetof(struct virtio_pci_common_cfg, num_queues)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS != - offsetof(struct virtio_pci_common_cfg, device_status)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION != - offsetof(struct virtio_pci_common_cfg, config_generation)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT != - offsetof(struct virtio_pci_common_cfg, queue_select)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE != - offsetof(struct virtio_pci_common_cfg, queue_size)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX != - offsetof(struct virtio_pci_common_cfg, queue_msix_vector)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE != - offsetof(struct virtio_pci_common_cfg, queue_enable)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF != - offsetof(struct virtio_pci_common_cfg, queue_notify_off)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO != - offsetof(struct virtio_pci_common_cfg, queue_desc_lo)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI != - offsetof(struct virtio_pci_common_cfg, queue_desc_hi)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO != - offsetof(struct virtio_pci_common_cfg, queue_avail_lo)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI != - offsetof(struct virtio_pci_common_cfg, queue_avail_hi)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO != - offsetof(struct virtio_pci_common_cfg, queue_used_lo)); - BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI != - offsetof(struct virtio_pci_common_cfg, queue_used_hi)); -} - -/* - * vp_modern_probe: probe the modern virtio pci device, note that the - * caller is required to enable PCI device before calling this function. - * @mdev: the modern virtio-pci device - * - * Return 0 on succeed otherwise fail - */ -static int vp_modern_probe(struct virtio_pci_modern_device *mdev) -{ - struct pci_dev *pci_dev = mdev->pci_dev; - int err, common, isr, notify, device; - u32 notify_length; - u32 notify_offset; - - check_offsets(); - - mdev->pci_dev = pci_dev; - - /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ - if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f) - return -ENODEV; - - if (pci_dev->device < 0x1040) { - /* Transitional devices: use the PCI subsystem device id as - * virtio device id, same as legacy driver always did. - */ - mdev->id.device = pci_dev->subsystem_device; - } else { - /* Modern devices: simply use PCI device id, but start from 0x1040. */ - mdev->id.device = pci_dev->device - 0x1040; - } - mdev->id.vendor = pci_dev->subsystem_vendor; - - /* check for a common config: if not, use legacy mode (bar 0). */ - common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, - IORESOURCE_IO | IORESOURCE_MEM, - &mdev->modern_bars); - if (!common) { - dev_info(&pci_dev->dev, - "virtio_pci: leaving for legacy driver\n"); - return -ENODEV; - } - - /* If common is there, these should be too... */ - isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, - IORESOURCE_IO | IORESOURCE_MEM, - &mdev->modern_bars); - notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, - IORESOURCE_IO | IORESOURCE_MEM, - &mdev->modern_bars); - if (!isr || !notify) { - dev_err(&pci_dev->dev, - "virtio_pci: missing capabilities %i/%i/%i\n", - common, isr, notify); - return -EINVAL; - } - - err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64)); - if (err) - err = dma_set_mask_and_coherent(&pci_dev->dev, - DMA_BIT_MASK(32)); - if (err) - dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); - - /* Device capability is only mandatory for devices that have - * device-specific configuration. - */ - device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, - IORESOURCE_IO | IORESOURCE_MEM, - &mdev->modern_bars); - - err = pci_request_selected_regions(pci_dev, mdev->modern_bars, - "virtio-pci-modern"); - if (err) - return err; - - err = -EINVAL; - mdev->common = vp_modern_map_capability(mdev, common, - sizeof(struct virtio_pci_common_cfg), 4, - 0, sizeof(struct virtio_pci_common_cfg), - NULL); - if (!mdev->common) - goto err_map_common; - mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1, - 0, 1, - NULL); - if (!mdev->isr) - goto err_map_isr; - - /* Read notify_off_multiplier from config space. */ - pci_read_config_dword(pci_dev, - notify + offsetof(struct virtio_pci_notify_cap, - notify_off_multiplier), - &mdev->notify_offset_multiplier); - /* Read notify length and offset from config space. */ - pci_read_config_dword(pci_dev, - notify + offsetof(struct virtio_pci_notify_cap, - cap.length), - ¬ify_length); - - pci_read_config_dword(pci_dev, - notify + offsetof(struct virtio_pci_notify_cap, - cap.offset), - ¬ify_offset); - - /* We don't know how many VQs we'll map, ahead of the time. - * If notify length is small, map it all now. - * Otherwise, map each VQ individually later. - */ - if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { - mdev->notify_base = vp_modern_map_capability(mdev, notify, - 2, 2, - 0, notify_length, - &mdev->notify_len); - if (!mdev->notify_base) - goto err_map_notify; - } else { - mdev->notify_map_cap = notify; - } - - /* Again, we don't know how much we should map, but PAGE_SIZE - * is more than enough for all existing devices. - */ - if (device) { - mdev->device = vp_modern_map_capability(mdev, device, 0, 4, - 0, PAGE_SIZE, - &mdev->device_len); - if (!mdev->device) - goto err_map_device; - } - - return 0; - -err_map_device: - if (mdev->notify_base) - pci_iounmap(pci_dev, mdev->notify_base); -err_map_notify: - pci_iounmap(pci_dev, mdev->isr); -err_map_isr: - pci_iounmap(pci_dev, mdev->common); -err_map_common: - return err; -} - /* the PCI probing function */ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) { @@ -1063,23 +463,6 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) return 0; } -/* - * vp_modern_probe: remove and cleanup the modern virtio pci device - * @mdev: the modern virtio-pci device - */ -static void vp_modern_remove(struct virtio_pci_modern_device *mdev) -{ - struct pci_dev *pci_dev = mdev->pci_dev; - - if (mdev->device) - pci_iounmap(pci_dev, mdev->device); - if (mdev->notify_base) - pci_iounmap(pci_dev, mdev->notify_base); - pci_iounmap(pci_dev, mdev->isr); - pci_iounmap(pci_dev, mdev->common); - pci_release_selected_regions(pci_dev, mdev->modern_bars); -} - void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) { struct virtio_pci_modern_device *mdev = &vp_dev->mdev; diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c new file mode 100644 index 000000000000..cbd667496bb1 --- /dev/null +++ b/drivers/virtio/virtio_pci_modern_dev.c @@ -0,0 +1,599 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/virtio_pci_modern.h> +#include <linux/module.h> +#include <linux/pci.h> + +/* + * vp_modern_map_capability - map a part of virtio pci capability + * @mdev: the modern virtio-pci device + * @off: offset of the capability + * @minlen: minimal length of the capability + * @align: align requirement + * @start: start from the capability + * @size: map size + * @len: the length that is actually mapped + * + * Returns the io address of for the part of the capability + */ +void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off, + size_t minlen, + u32 align, + u32 start, u32 size, + size_t *len) +{ + struct pci_dev *dev = mdev->pci_dev; + u8 bar; + u32 offset, length; + void __iomem *p; + + pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, + bar), + &bar); + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), + &offset); + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), + &length); + + if (length <= start) { + dev_err(&dev->dev, + "virtio_pci: bad capability len %u (>%u expected)\n", + length, start); + return NULL; + } + + if (length - start < minlen) { + dev_err(&dev->dev, + "virtio_pci: bad capability len %u (>=%zu expected)\n", + length, minlen); + return NULL; + } + + length -= start; + + if (start + offset < offset) { + dev_err(&dev->dev, + "virtio_pci: map wrap-around %u+%u\n", + start, offset); + return NULL; + } + + offset += start; + + if (offset & (align - 1)) { + dev_err(&dev->dev, + "virtio_pci: offset %u not aligned to %u\n", + offset, align); + return NULL; + } + + if (length > size) + length = size; + + if (len) + *len = length; + + if (minlen + offset < minlen || + minlen + offset > pci_resource_len(dev, bar)) { + dev_err(&dev->dev, + "virtio_pci: map virtio %zu@%u " + "out of range on bar %i length %lu\n", + minlen, offset, + bar, (unsigned long)pci_resource_len(dev, bar)); + return NULL; + } + + p = pci_iomap_range(dev, bar, offset, length); + if (!p) + dev_err(&dev->dev, + "virtio_pci: unable to map virtio %u@%u on bar %i\n", + length, offset, bar); + return p; +} +EXPORT_SYMBOL_GPL(vp_modern_map_capability); + +/** + * virtio_pci_find_capability - walk capabilities to find device info. + * @dev: the pci device + * @cfg_type: the VIRTIO_PCI_CAP_* value we seek + * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. + * @bars: the bitmask of BARs + * + * Returns offset of the capability, or 0. + */ +static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, + u32 ioresource_types, int *bars) +{ + int pos; + + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); + pos > 0; + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { + u8 type, bar; + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cfg_type), + &type); + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + bar), + &bar); + + /* Ignore structures with reserved BAR values */ + if (bar > 0x5) + continue; + + if (type == cfg_type) { + if (pci_resource_len(dev, bar) && + pci_resource_flags(dev, bar) & ioresource_types) { + *bars |= (1 << bar); + return pos; + } + } + } + return 0; +} + +/* This is part of the ABI. Don't screw with it. */ +static inline void check_offsets(void) +{ + /* Note: disk space was harmed in compilation of this function. */ + BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR != + offsetof(struct virtio_pci_cap, cap_vndr)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT != + offsetof(struct virtio_pci_cap, cap_next)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN != + offsetof(struct virtio_pci_cap, cap_len)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE != + offsetof(struct virtio_pci_cap, cfg_type)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR != + offsetof(struct virtio_pci_cap, bar)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET != + offsetof(struct virtio_pci_cap, offset)); + BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH != + offsetof(struct virtio_pci_cap, length)); + BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT != + offsetof(struct virtio_pci_notify_cap, + notify_off_multiplier)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT != + offsetof(struct virtio_pci_common_cfg, + device_feature_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF != + offsetof(struct virtio_pci_common_cfg, device_feature)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT != + offsetof(struct virtio_pci_common_cfg, + guest_feature_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF != + offsetof(struct virtio_pci_common_cfg, guest_feature)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX != + offsetof(struct virtio_pci_common_cfg, msix_config)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ != + offsetof(struct virtio_pci_common_cfg, num_queues)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS != + offsetof(struct virtio_pci_common_cfg, device_status)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION != + offsetof(struct virtio_pci_common_cfg, config_generation)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT != + offsetof(struct virtio_pci_common_cfg, queue_select)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE != + offsetof(struct virtio_pci_common_cfg, queue_size)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX != + offsetof(struct virtio_pci_common_cfg, queue_msix_vector)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE != + offsetof(struct virtio_pci_common_cfg, queue_enable)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF != + offsetof(struct virtio_pci_common_cfg, queue_notify_off)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO != + offsetof(struct virtio_pci_common_cfg, queue_desc_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI != + offsetof(struct virtio_pci_common_cfg, queue_desc_hi)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO != + offsetof(struct virtio_pci_common_cfg, queue_avail_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI != + offsetof(struct virtio_pci_common_cfg, queue_avail_hi)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO != + offsetof(struct virtio_pci_common_cfg, queue_used_lo)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI != + offsetof(struct virtio_pci_common_cfg, queue_used_hi)); +} + +/* + * vp_modern_probe: probe the modern virtio pci device, note that the + * caller is required to enable PCI device before calling this function. + * @mdev: the modern virtio-pci device + * + * Return 0 on succeed otherwise fail + */ +int vp_modern_probe(struct virtio_pci_modern_device *mdev) +{ + struct pci_dev *pci_dev = mdev->pci_dev; + int err, common, isr, notify, device; + u32 notify_length; + u32 notify_offset; + + check_offsets(); + + mdev->pci_dev = pci_dev; + + /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ + if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f) + return -ENODEV; + + if (pci_dev->device < 0x1040) { + /* Transitional devices: use the PCI subsystem device id as + * virtio device id, same as legacy driver always did. + */ + mdev->id.device = pci_dev->subsystem_device; + } else { + /* Modern devices: simply use PCI device id, but start from 0x1040. */ + mdev->id.device = pci_dev->device - 0x1040; + } + mdev->id.vendor = pci_dev->subsystem_vendor; + + /* check for a common config: if not, use legacy mode (bar 0). */ + common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + if (!common) { + dev_info(&pci_dev->dev, + "virtio_pci: leaving for legacy driver\n"); + return -ENODEV; + } + + /* If common is there, these should be too... */ + isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + if (!isr || !notify) { + dev_err(&pci_dev->dev, + "virtio_pci: missing capabilities %i/%i/%i\n", + common, isr, notify); + return -EINVAL; + } + + err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64)); + if (err) + err = dma_set_mask_and_coherent(&pci_dev->dev, + DMA_BIT_MASK(32)); + if (err) + dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + /* Device capability is only mandatory for devices that have + * device-specific configuration. + */ + device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &mdev->modern_bars); + + err = pci_request_selected_regions(pci_dev, mdev->modern_bars, + "virtio-pci-modern"); + if (err) + return err; + + err = -EINVAL; + mdev->common = vp_modern_map_capability(mdev, common, + sizeof(struct virtio_pci_common_cfg), 4, + 0, sizeof(struct virtio_pci_common_cfg), + NULL); + if (!mdev->common) + goto err_map_common; + mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1, + 0, 1, + NULL); + if (!mdev->isr) + goto err_map_isr; + + /* Read notify_off_multiplier from config space. */ + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + notify_off_multiplier), + &mdev->notify_offset_multiplier); + /* Read notify length and offset from config space. */ + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + cap.length), + ¬ify_length); + + pci_read_config_dword(pci_dev, + notify + offsetof(struct virtio_pci_notify_cap, + cap.offset), + ¬ify_offset); + + /* We don't know how many VQs we'll map, ahead of the time. + * If notify length is small, map it all now. + * Otherwise, map each VQ individually later. + */ + if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { + mdev->notify_base = vp_modern_map_capability(mdev, notify, + 2, 2, + 0, notify_length, + &mdev->notify_len); + if (!mdev->notify_base) + goto err_map_notify; + } else { + mdev->notify_map_cap = notify; + } + + /* Again, we don't know how much we should map, but PAGE_SIZE + * is more than enough for all existing devices. + */ + if (device) { + mdev->device = vp_modern_map_capability(mdev, device, 0, 4, + 0, PAGE_SIZE, + &mdev->device_len); + if (!mdev->device) + goto err_map_device; + } + + return 0; + +err_map_device: + if (mdev->notify_base) + pci_iounmap(pci_dev, mdev->notify_base); +err_map_notify: + pci_iounmap(pci_dev, mdev->isr); +err_map_isr: + pci_iounmap(pci_dev, mdev->common); +err_map_common: + return err; +} +EXPORT_SYMBOL_GPL(vp_modern_probe); + +/* + * vp_modern_probe: remove and cleanup the modern virtio pci device + * @mdev: the modern virtio-pci device + */ +void vp_modern_remove(struct virtio_pci_modern_device *mdev) +{ + struct pci_dev *pci_dev = mdev->pci_dev; + + if (mdev->device) + pci_iounmap(pci_dev, mdev->device); + if (mdev->notify_base) + pci_iounmap(pci_dev, mdev->notify_base); + pci_iounmap(pci_dev, mdev->isr); + pci_iounmap(pci_dev, mdev->common); + pci_release_selected_regions(pci_dev, mdev->modern_bars); +} +EXPORT_SYMBOL_GPL(vp_modern_remove); + +/* + * vp_modern_get_features - get features from device + * @mdev: the modern virtio-pci device + * + * Returns the features read from the device + */ +u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + u64 features; + + vp_iowrite32(0, &cfg->device_feature_select); + features = vp_ioread32(&cfg->device_feature); + vp_iowrite32(1, &cfg->device_feature_select); + features |= ((u64)vp_ioread32(&cfg->device_feature) << 32); + + return features; +} +EXPORT_SYMBOL_GPL(vp_modern_get_features); + +/* + * vp_modern_set_features - set features to device + * @mdev: the modern virtio-pci device + * @features: the features set to device + */ +void vp_modern_set_features(struct virtio_pci_modern_device *mdev, + u64 features) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite32(0, &cfg->guest_feature_select); + vp_iowrite32((u32)features, &cfg->guest_feature); + vp_iowrite32(1, &cfg->guest_feature_select); + vp_iowrite32(features >> 32, &cfg->guest_feature); +} +EXPORT_SYMBOL_GPL(vp_modern_set_features); + +/* + * vp_modern_generation - get the device genreation + * @mdev: the modern virtio-pci device + * + * Returns the genreation read from device + */ +u32 vp_modern_generation(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + return vp_ioread8(&cfg->config_generation); +} +EXPORT_SYMBOL_GPL(vp_modern_generation); + +/* + * vp_modern_get_status - get the device status + * @mdev: the modern virtio-pci device + * + * Returns the status read from device + */ +u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + return vp_ioread8(&cfg->device_status); +} +EXPORT_SYMBOL_GPL(vp_modern_get_status); + +/* + * vp_modern_set_status - set status to device + * @mdev: the modern virtio-pci device + * @status: the status set to device + */ +void vp_modern_set_status(struct virtio_pci_modern_device *mdev, + u8 status) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite8(status, &cfg->device_status); +} +EXPORT_SYMBOL_GPL(vp_modern_set_status); + +/* + * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue + * @mdev: the modern virtio-pci device + * @index: queue index + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev, + u16 index, u16 vector) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite16(index, &cfg->queue_select); + vp_iowrite16(vector, &cfg->queue_msix_vector); + /* Flush the write out to device */ + return vp_ioread16(&cfg->queue_msix_vector); +} +EXPORT_SYMBOL_GPL(vp_modern_queue_vector); + +/* + * vp_modern_config_vector - set the vector for config interrupt + * @mdev: the modern virtio-pci device + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev, + u16 vector) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + /* Setup the vector used for configuration events */ + vp_iowrite16(vector, &cfg->msix_config); + /* Verify we had enough resources to assign the vector */ + /* Will also flush the write out to device */ + return vp_ioread16(&cfg->msix_config); +} +EXPORT_SYMBOL_GPL(vp_modern_config_vector); + +/* + * vp_modern_queue_address - set the virtqueue address + * @mdev: the modern virtio-pci device + * @index: the queue index + * @desc_addr: address of the descriptor area + * @driver_addr: address of the driver area + * @device_addr: address of the device area + */ +void vp_modern_queue_address(struct virtio_pci_modern_device *mdev, + u16 index, u64 desc_addr, u64 driver_addr, + u64 device_addr) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + vp_iowrite16(index, &cfg->queue_select); + + vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo, + &cfg->queue_desc_hi); + vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo, + &cfg->queue_avail_hi); + vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo, + &cfg->queue_used_hi); +} +EXPORT_SYMBOL_GPL(vp_modern_queue_address); + +/* + * vp_modern_set_queue_enable - enable a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * @enable: whether the virtqueue is enable or not + */ +void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev, + u16 index, bool enable) +{ + vp_iowrite16(index, &mdev->common->queue_select); + vp_iowrite16(enable, &mdev->common->queue_enable); +} +EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable); + +/* + * vp_modern_get_queue_enable - enable a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns whether a virtqueue is enabled or not + */ +bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_enable); +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable); + +/* + * vp_modern_set_queue_size - set size for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * @size: the size of the virtqueue + */ +void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev, + u16 index, u16 size) +{ + vp_iowrite16(index, &mdev->common->queue_select); + vp_iowrite16(size, &mdev->common->queue_size); + +} +EXPORT_SYMBOL_GPL(vp_modern_set_queue_size); + +/* + * vp_modern_get_queue_size - get size for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns the size of the virtqueue + */ +u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_size); + +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_size); + +/* + * vp_modern_get_num_queues - get the number of virtqueues + * @mdev: the modern virtio-pci device + * + * Returns the number of virtqueues + */ +u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev) +{ + return vp_ioread16(&mdev->common->num_queues); +} +EXPORT_SYMBOL_GPL(vp_modern_get_num_queues); + +/* + * vp_modern_get_queue_notify_off - get notification offset for a virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns the notification offset for a virtqueue + */ +u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev, + u16 index) +{ + vp_iowrite16(index, &mdev->common->queue_select); + + return vp_ioread16(&mdev->common->queue_notify_off); +} +EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off); + +MODULE_VERSION("0.1"); +MODULE_DESCRIPTION("Modern Virtio PCI Device"); +MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>"); +MODULE_LICENSE("GPL"); |