From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 458 +++++++++++++++++++++++++++++++++++ 1 file changed, 458 insertions(+) create mode 100644 drivers/vdpa/vdpa_sim/vdpa_sim_blk.c (limited to 'drivers/vdpa/vdpa_sim/vdpa_sim_blk.c') diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c new file mode 100644 index 000000000..f74592623 --- /dev/null +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -0,0 +1,458 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VDPA simulator for block device. + * + * Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved. + * Copyright (c) 2021, Red Hat Inc. All rights reserved. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "vdpa_sim.h" + +#define DRV_VERSION "0.1" +#define DRV_AUTHOR "Max Gurtovoy " +#define DRV_DESC "vDPA Device Simulator for block device" +#define DRV_LICENSE "GPL v2" + +#define VDPASIM_BLK_FEATURES (VDPASIM_FEATURES | \ + (1ULL << VIRTIO_BLK_F_FLUSH) | \ + (1ULL << VIRTIO_BLK_F_SIZE_MAX) | \ + (1ULL << VIRTIO_BLK_F_SEG_MAX) | \ + (1ULL << VIRTIO_BLK_F_BLK_SIZE) | \ + (1ULL << VIRTIO_BLK_F_TOPOLOGY) | \ + (1ULL << VIRTIO_BLK_F_MQ) | \ + (1ULL << VIRTIO_BLK_F_DISCARD) | \ + (1ULL << VIRTIO_BLK_F_WRITE_ZEROES)) + +#define VDPASIM_BLK_CAPACITY 0x40000 +#define VDPASIM_BLK_SIZE_MAX 0x1000 +#define VDPASIM_BLK_SEG_MAX 32 +#define VDPASIM_BLK_DWZ_MAX_SECTORS UINT_MAX + +/* 1 virtqueue, 1 address space, 1 virtqueue group */ +#define VDPASIM_BLK_VQ_NUM 1 +#define VDPASIM_BLK_AS_NUM 1 +#define VDPASIM_BLK_GROUP_NUM 1 + +static char vdpasim_blk_id[VIRTIO_BLK_ID_BYTES] = "vdpa_blk_sim"; + +static bool vdpasim_blk_check_range(struct vdpasim *vdpasim, u64 start_sector, + u64 num_sectors, u64 max_sectors) +{ + if (start_sector > VDPASIM_BLK_CAPACITY) { + dev_dbg(&vdpasim->vdpa.dev, + "starting sector exceeds the capacity - start: 0x%llx capacity: 0x%x\n", + start_sector, VDPASIM_BLK_CAPACITY); + } + + if (num_sectors > max_sectors) { + dev_dbg(&vdpasim->vdpa.dev, + "number of sectors exceeds the max allowed in a request - num: 0x%llx max: 0x%llx\n", + num_sectors, max_sectors); + return false; + } + + if (num_sectors > VDPASIM_BLK_CAPACITY - start_sector) { + dev_dbg(&vdpasim->vdpa.dev, + "request exceeds the capacity - start: 0x%llx num: 0x%llx capacity: 0x%x\n", + start_sector, num_sectors, VDPASIM_BLK_CAPACITY); + return false; + } + + return true; +} + +/* Returns 'true' if the request is handled (with or without an I/O error) + * and the status is correctly written in the last byte of the 'in iov', + * 'false' otherwise. + */ +static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim, + struct vdpasim_virtqueue *vq) +{ + size_t pushed = 0, to_pull, to_push; + struct virtio_blk_outhdr hdr; + bool handled = false; + ssize_t bytes; + loff_t offset; + u64 sector; + u8 status; + u32 type; + int ret; + + ret = vringh_getdesc_iotlb(&vq->vring, &vq->out_iov, &vq->in_iov, + &vq->head, GFP_ATOMIC); + if (ret != 1) + return false; + + if (vq->out_iov.used < 1 || vq->in_iov.used < 1) { + dev_dbg(&vdpasim->vdpa.dev, "missing headers - out_iov: %u in_iov %u\n", + vq->out_iov.used, vq->in_iov.used); + goto err; + } + + if (vq->in_iov.iov[vq->in_iov.used - 1].iov_len < 1) { + dev_dbg(&vdpasim->vdpa.dev, "request in header too short\n"); + goto err; + } + + /* The last byte is the status and we checked if the last iov has + * enough room for it. + */ + to_push = vringh_kiov_length(&vq->in_iov) - 1; + + to_pull = vringh_kiov_length(&vq->out_iov); + + bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, &hdr, + sizeof(hdr)); + if (bytes != sizeof(hdr)) { + dev_dbg(&vdpasim->vdpa.dev, "request out header too short\n"); + goto err; + } + + to_pull -= bytes; + + type = vdpasim32_to_cpu(vdpasim, hdr.type); + sector = vdpasim64_to_cpu(vdpasim, hdr.sector); + offset = sector << SECTOR_SHIFT; + status = VIRTIO_BLK_S_OK; + + if (type != VIRTIO_BLK_T_IN && type != VIRTIO_BLK_T_OUT && + sector != 0) { + dev_dbg(&vdpasim->vdpa.dev, + "sector must be 0 for %u request - sector: 0x%llx\n", + type, sector); + status = VIRTIO_BLK_S_IOERR; + goto err_status; + } + + switch (type) { + case VIRTIO_BLK_T_IN: + if (!vdpasim_blk_check_range(vdpasim, sector, + to_push >> SECTOR_SHIFT, + VDPASIM_BLK_SIZE_MAX * VDPASIM_BLK_SEG_MAX)) { + status = VIRTIO_BLK_S_IOERR; + break; + } + + bytes = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, + vdpasim->buffer + offset, + to_push); + if (bytes < 0) { + dev_dbg(&vdpasim->vdpa.dev, + "vringh_iov_push_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n", + bytes, offset, to_push); + status = VIRTIO_BLK_S_IOERR; + break; + } + + pushed += bytes; + break; + + case VIRTIO_BLK_T_OUT: + if (!vdpasim_blk_check_range(vdpasim, sector, + to_pull >> SECTOR_SHIFT, + VDPASIM_BLK_SIZE_MAX * VDPASIM_BLK_SEG_MAX)) { + status = VIRTIO_BLK_S_IOERR; + break; + } + + bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, + vdpasim->buffer + offset, + to_pull); + if (bytes < 0) { + dev_dbg(&vdpasim->vdpa.dev, + "vringh_iov_pull_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n", + bytes, offset, to_pull); + status = VIRTIO_BLK_S_IOERR; + break; + } + break; + + case VIRTIO_BLK_T_GET_ID: + bytes = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, + vdpasim_blk_id, + VIRTIO_BLK_ID_BYTES); + if (bytes < 0) { + dev_dbg(&vdpasim->vdpa.dev, + "vringh_iov_push_iotlb() error: %zd\n", bytes); + status = VIRTIO_BLK_S_IOERR; + break; + } + + pushed += bytes; + break; + + case VIRTIO_BLK_T_FLUSH: + /* nothing to do */ + break; + + case VIRTIO_BLK_T_DISCARD: + case VIRTIO_BLK_T_WRITE_ZEROES: { + struct virtio_blk_discard_write_zeroes range; + u32 num_sectors, flags; + + if (to_pull != sizeof(range)) { + dev_dbg(&vdpasim->vdpa.dev, + "discard/write_zeroes header len: 0x%zx [expected: 0x%zx]\n", + to_pull, sizeof(range)); + status = VIRTIO_BLK_S_IOERR; + break; + } + + bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, &range, + to_pull); + if (bytes < 0) { + dev_dbg(&vdpasim->vdpa.dev, + "vringh_iov_pull_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n", + bytes, offset, to_pull); + status = VIRTIO_BLK_S_IOERR; + break; + } + + sector = le64_to_cpu(range.sector); + offset = sector << SECTOR_SHIFT; + num_sectors = le32_to_cpu(range.num_sectors); + flags = le32_to_cpu(range.flags); + + if (type == VIRTIO_BLK_T_DISCARD && flags != 0) { + dev_dbg(&vdpasim->vdpa.dev, + "discard unexpected flags set - flags: 0x%x\n", + flags); + status = VIRTIO_BLK_S_UNSUPP; + break; + } + + if (type == VIRTIO_BLK_T_WRITE_ZEROES && + flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) { + dev_dbg(&vdpasim->vdpa.dev, + "write_zeroes unexpected flags set - flags: 0x%x\n", + flags); + status = VIRTIO_BLK_S_UNSUPP; + break; + } + + if (!vdpasim_blk_check_range(vdpasim, sector, num_sectors, + VDPASIM_BLK_DWZ_MAX_SECTORS)) { + status = VIRTIO_BLK_S_IOERR; + break; + } + + if (type == VIRTIO_BLK_T_WRITE_ZEROES) { + memset(vdpasim->buffer + offset, 0, + num_sectors << SECTOR_SHIFT); + } + + break; + } + default: + dev_dbg(&vdpasim->vdpa.dev, + "Unsupported request type %d\n", type); + status = VIRTIO_BLK_S_IOERR; + break; + } + +err_status: + /* If some operations fail, we need to skip the remaining bytes + * to put the status in the last byte + */ + if (to_push - pushed > 0) + vringh_kiov_advance(&vq->in_iov, to_push - pushed); + + /* Last byte is the status */ + bytes = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, &status, 1); + if (bytes != 1) + goto err; + + pushed += bytes; + + /* Make sure data is wrote before advancing index */ + smp_wmb(); + + handled = true; + +err: + vringh_complete_iotlb(&vq->vring, vq->head, pushed); + + return handled; +} + +static void vdpasim_blk_work(struct work_struct *work) +{ + struct vdpasim *vdpasim = container_of(work, struct vdpasim, work); + bool reschedule = false; + int i; + + spin_lock(&vdpasim->lock); + + if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) + goto out; + + if (!vdpasim->running) + goto out; + + for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) { + struct vdpasim_virtqueue *vq = &vdpasim->vqs[i]; + int reqs = 0; + + if (!vq->ready) + continue; + + while (vdpasim_blk_handle_req(vdpasim, vq)) { + /* Make sure used is visible before rasing the interrupt. */ + smp_wmb(); + + local_bh_disable(); + if (vringh_need_notify_iotlb(&vq->vring) > 0) + vringh_notify(&vq->vring); + local_bh_enable(); + + if (++reqs > 4) { + reschedule = true; + break; + } + } + } +out: + spin_unlock(&vdpasim->lock); + + if (reschedule) + schedule_work(&vdpasim->work); +} + +static void vdpasim_blk_get_config(struct vdpasim *vdpasim, void *config) +{ + struct virtio_blk_config *blk_config = config; + + memset(config, 0, sizeof(struct virtio_blk_config)); + + blk_config->capacity = cpu_to_vdpasim64(vdpasim, VDPASIM_BLK_CAPACITY); + blk_config->size_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SIZE_MAX); + blk_config->seg_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SEG_MAX); + blk_config->num_queues = cpu_to_vdpasim16(vdpasim, VDPASIM_BLK_VQ_NUM); + blk_config->min_io_size = cpu_to_vdpasim16(vdpasim, 1); + blk_config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1); + blk_config->blk_size = cpu_to_vdpasim32(vdpasim, SECTOR_SIZE); + /* VIRTIO_BLK_F_DISCARD */ + blk_config->discard_sector_alignment = + cpu_to_vdpasim32(vdpasim, SECTOR_SIZE); + blk_config->max_discard_sectors = + cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS); + blk_config->max_discard_seg = cpu_to_vdpasim32(vdpasim, 1); + /* VIRTIO_BLK_F_WRITE_ZEROES */ + blk_config->max_write_zeroes_sectors = + cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS); + blk_config->max_write_zeroes_seg = cpu_to_vdpasim32(vdpasim, 1); + +} + +static void vdpasim_blk_mgmtdev_release(struct device *dev) +{ +} + +static struct device vdpasim_blk_mgmtdev = { + .init_name = "vdpasim_blk", + .release = vdpasim_blk_mgmtdev_release, +}; + +static int vdpasim_blk_dev_add(struct vdpa_mgmt_dev *mdev, const char *name, + const struct vdpa_dev_set_config *config) +{ + struct vdpasim_dev_attr dev_attr = {}; + struct vdpasim *simdev; + int ret; + + dev_attr.mgmt_dev = mdev; + dev_attr.name = name; + dev_attr.id = VIRTIO_ID_BLOCK; + dev_attr.supported_features = VDPASIM_BLK_FEATURES; + dev_attr.nvqs = VDPASIM_BLK_VQ_NUM; + dev_attr.ngroups = VDPASIM_BLK_GROUP_NUM; + dev_attr.nas = VDPASIM_BLK_AS_NUM; + dev_attr.config_size = sizeof(struct virtio_blk_config); + dev_attr.get_config = vdpasim_blk_get_config; + dev_attr.work_fn = vdpasim_blk_work; + dev_attr.buffer_size = VDPASIM_BLK_CAPACITY << SECTOR_SHIFT; + + simdev = vdpasim_create(&dev_attr, config); + if (IS_ERR(simdev)) + return PTR_ERR(simdev); + + ret = _vdpa_register_device(&simdev->vdpa, VDPASIM_BLK_VQ_NUM); + if (ret) + goto put_dev; + + return 0; + +put_dev: + put_device(&simdev->vdpa.dev); + return ret; +} + +static void vdpasim_blk_dev_del(struct vdpa_mgmt_dev *mdev, + struct vdpa_device *dev) +{ + struct vdpasim *simdev = container_of(dev, struct vdpasim, vdpa); + + _vdpa_unregister_device(&simdev->vdpa); +} + +static const struct vdpa_mgmtdev_ops vdpasim_blk_mgmtdev_ops = { + .dev_add = vdpasim_blk_dev_add, + .dev_del = vdpasim_blk_dev_del +}; + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct vdpa_mgmt_dev mgmt_dev = { + .device = &vdpasim_blk_mgmtdev, + .id_table = id_table, + .ops = &vdpasim_blk_mgmtdev_ops, +}; + +static int __init vdpasim_blk_init(void) +{ + int ret; + + ret = device_register(&vdpasim_blk_mgmtdev); + if (ret) { + put_device(&vdpasim_blk_mgmtdev); + return ret; + } + + ret = vdpa_mgmtdev_register(&mgmt_dev); + if (ret) + goto parent_err; + + return 0; + +parent_err: + device_unregister(&vdpasim_blk_mgmtdev); + return ret; +} + +static void __exit vdpasim_blk_exit(void) +{ + vdpa_mgmtdev_unregister(&mgmt_dev); + device_unregister(&vdpasim_blk_mgmtdev); +} + +module_init(vdpasim_blk_init) +module_exit(vdpasim_blk_exit) + +MODULE_VERSION(DRV_VERSION); +MODULE_LICENSE(DRV_LICENSE); +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); -- cgit v1.2.3