From db5d00c93edc0afba1027e51ff3b38dc0e5f7728 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 21 Jun 2019 14:45:18 +0300 Subject: [PATCH 1/9] libnvdimm, namespace: Drop uuid_t implementation detail There is no need for caller to know how uuid_t type is constructed. Thus, whenever we use it the implementation details are not needed. Drop it for good. Signed-off-by: Andy Shevchenko Signed-off-by: Dan Williams --- drivers/nvdimm/namespace_devs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c index a434a5964cb9..2d8d7e554877 100644 --- a/drivers/nvdimm/namespace_devs.c +++ b/drivers/nvdimm/namespace_devs.c @@ -1822,8 +1822,8 @@ static bool has_uuid_at_pos(struct nd_region *nd_region, u8 *uuid, && !guid_equal(&nd_set->type_guid, &nd_label->type_guid)) { dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n", - nd_set->type_guid.b, - nd_label->type_guid.b); + &nd_set->type_guid, + &nd_label->type_guid); continue; } @@ -2227,8 +2227,8 @@ static struct device *create_namespace_blk(struct nd_region *nd_region, if (namespace_label_has(ndd, type_guid)) { if (!guid_equal(&nd_set->type_guid, &nd_label->type_guid)) { dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n", - nd_set->type_guid.b, - nd_label->type_guid.b); + &nd_set->type_guid, + &nd_label->type_guid); return ERR_PTR(-EAGAIN); } From c5d4355d10d414a96ca870b731756b89d068d57a Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:22 +0530 Subject: [PATCH 2/9] libnvdimm: nd_region flush callback support This patch adds functionality to perform flush from guest to host over VIRTIO. We are registering a callback based on 'nd_region' type. virtio_pmem driver requires this special flush function. For rest of the region types we are registering existing flush function. Report error returned by host fsync failure to userspace. Signed-off-by: Pankaj Gupta Signed-off-by: Dan Williams --- drivers/acpi/nfit/core.c | 4 ++-- drivers/nvdimm/claim.c | 6 ++++-- drivers/nvdimm/nd.h | 1 + drivers/nvdimm/pmem.c | 13 ++++++++----- drivers/nvdimm/region_devs.c | 26 ++++++++++++++++++++++++-- include/linux/libnvdimm.h | 9 ++++++++- 6 files changed, 47 insertions(+), 12 deletions(-) diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 23022cf20d26..c02fa27dd3f3 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -2426,7 +2426,7 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw, offset = to_interleave_offset(offset, mmio); writeq(cmd, mmio->addr.base + offset); - nvdimm_flush(nfit_blk->nd_region); + nvdimm_flush(nfit_blk->nd_region, NULL); if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH) readq(mmio->addr.base + offset); @@ -2475,7 +2475,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk, } if (rw) - nvdimm_flush(nfit_blk->nd_region); + nvdimm_flush(nfit_blk->nd_region, NULL); rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0; return rc; diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c index 26c1c7618891..2985ca949912 100644 --- a/drivers/nvdimm/claim.c +++ b/drivers/nvdimm/claim.c @@ -255,7 +255,7 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns, struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512); sector_t sector = offset >> 9; - int rc = 0; + int rc = 0, ret = 0; if (unlikely(!size)) return 0; @@ -293,7 +293,9 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns, } memcpy_flushcache(nsio->addr + offset, buf, size); - nvdimm_flush(to_nd_region(ndns->dev.parent)); + ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL); + if (ret) + rc = ret; return rc; } diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index d24304c0e6d7..1b9955651379 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -155,6 +155,7 @@ struct nd_region { struct badblocks bb; struct nd_interleave_set *nd_set; struct nd_percpu_lane __percpu *lane; + int (*flush)(struct nd_region *nd_region, struct bio *bio); struct nd_mapping mapping[0]; }; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 24d7fe7c74ed..223da63d1bd7 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -184,6 +184,7 @@ static blk_status_t pmem_do_bvec(struct pmem_device *pmem, struct page *page, static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio) { + int ret = 0; blk_status_t rc = 0; bool do_acct; unsigned long start; @@ -193,7 +194,7 @@ static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio) struct nd_region *nd_region = to_region(pmem); if (bio->bi_opf & REQ_PREFLUSH) - nvdimm_flush(nd_region); + ret = nvdimm_flush(nd_region, bio); do_acct = nd_iostat_start(bio, &start); bio_for_each_segment(bvec, bio, iter) { @@ -208,7 +209,10 @@ static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio) nd_iostat_end(bio, start); if (bio->bi_opf & REQ_FUA) - nvdimm_flush(nd_region); + ret = nvdimm_flush(nd_region, bio); + + if (ret) + bio->bi_status = errno_to_blk_status(ret); bio_endio(bio); return BLK_QC_T_NONE; @@ -477,7 +481,6 @@ static int pmem_attach_disk(struct device *dev, } dax_write_cache(dax_dev, nvdimm_has_cache(nd_region)); pmem->dax_dev = dax_dev; - gendev = disk_to_dev(disk); gendev->groups = pmem_attribute_groups; @@ -535,14 +538,14 @@ static int nd_pmem_remove(struct device *dev) sysfs_put(pmem->bb_state); pmem->bb_state = NULL; } - nvdimm_flush(to_nd_region(dev->parent)); + nvdimm_flush(to_nd_region(dev->parent), NULL); return 0; } static void nd_pmem_shutdown(struct device *dev) { - nvdimm_flush(to_nd_region(dev->parent)); + nvdimm_flush(to_nd_region(dev->parent), NULL); } static void nd_pmem_notify(struct device *dev, enum nvdimm_event event) diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 4fed9ce9c2fe..eca2e62af134 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -287,7 +287,9 @@ static ssize_t deep_flush_store(struct device *dev, struct device_attribute *att return rc; if (!flush) return -EINVAL; - nvdimm_flush(nd_region); + rc = nvdimm_flush(nd_region, NULL); + if (rc) + return rc; return len; } @@ -1077,6 +1079,11 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus, dev->of_node = ndr_desc->of_node; nd_region->ndr_size = resource_size(ndr_desc->res); nd_region->ndr_start = ndr_desc->res->start; + if (ndr_desc->flush) + nd_region->flush = ndr_desc->flush; + else + nd_region->flush = NULL; + nd_device_register(dev); return nd_region; @@ -1117,11 +1124,24 @@ struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus, } EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create); +int nvdimm_flush(struct nd_region *nd_region, struct bio *bio) +{ + int rc = 0; + + if (!nd_region->flush) + rc = generic_nvdimm_flush(nd_region); + else { + if (nd_region->flush(nd_region, bio)) + rc = -EIO; + } + + return rc; +} /** * nvdimm_flush - flush any posted write queues between the cpu and pmem media * @nd_region: blk or interleaved pmem region */ -void nvdimm_flush(struct nd_region *nd_region) +int generic_nvdimm_flush(struct nd_region *nd_region) { struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev); int i, idx; @@ -1145,6 +1165,8 @@ void nvdimm_flush(struct nd_region *nd_region) if (ndrd_get_flush_wpq(ndrd, i, 0)) writeq(1, ndrd_get_flush_wpq(ndrd, i, idx)); wmb(); + + return 0; } EXPORT_SYMBOL_GPL(nvdimm_flush); diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index 03d5c3aece9d..e13100f424c8 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -11,6 +11,7 @@ #include #include #include +#include struct badrange_entry { u64 start; @@ -57,6 +58,9 @@ enum { */ ND_REGION_PERSIST_MEMCTRL = 2, + /* Platform provides asynchronous flush mechanism */ + ND_REGION_ASYNC = 3, + /* mark newly adjusted resources as requiring a label update */ DPA_RESOURCE_ADJUSTED = 1 << 0, }; @@ -113,6 +117,7 @@ struct nd_mapping_desc { int position; }; +struct nd_region; struct nd_region_desc { struct resource *res; struct nd_mapping_desc *mapping; @@ -125,6 +130,7 @@ struct nd_region_desc { int target_node; unsigned long flags; struct device_node *of_node; + int (*flush)(struct nd_region *nd_region, struct bio *bio); }; struct device; @@ -252,7 +258,8 @@ unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr); unsigned int nd_region_acquire_lane(struct nd_region *nd_region); void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane); u64 nd_fletcher64(void *addr, size_t len, bool le); -void nvdimm_flush(struct nd_region *nd_region); +int nvdimm_flush(struct nd_region *nd_region, struct bio *bio); +int generic_nvdimm_flush(struct nd_region *nd_region); int nvdimm_has_flush(struct nd_region *nd_region); int nvdimm_has_cache(struct nd_region *nd_region); int nvdimm_in_overwrite(struct nvdimm *nvdimm); From 6e84200c0a2994b991259d19450eee561029bf70 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:23 +0530 Subject: [PATCH 3/9] virtio-pmem: Add virtio pmem driver This patch adds virtio-pmem driver for KVM guest. Guest reads the persistent memory range information from Qemu over VIRTIO and registers it on nvdimm_bus. It also creates a nd_region object with the persistent memory range information so that existing 'nvdimm/pmem' driver can reserve this into system memory map. This way 'virtio-pmem' driver uses existing functionality of pmem driver to register persistent memory compatible for DAX capable filesystems. This also provides function to perform guest flush over VIRTIO from 'pmem' driver when userspace performs flush on DAX memory range. Signed-off-by: Pankaj Gupta Reviewed-by: Yuval Shaia Acked-by: Michael S. Tsirkin Acked-by: Jakub Staron Tested-by: Jakub Staron Reviewed-by: Cornelia Huck Signed-off-by: Dan Williams --- drivers/nvdimm/Makefile | 1 + drivers/nvdimm/nd_virtio.c | 125 +++++++++++++++++++++++++++++++ drivers/nvdimm/virtio_pmem.c | 122 ++++++++++++++++++++++++++++++ drivers/nvdimm/virtio_pmem.h | 55 ++++++++++++++ drivers/virtio/Kconfig | 11 +++ include/uapi/linux/virtio_ids.h | 1 + include/uapi/linux/virtio_pmem.h | 34 +++++++++ 7 files changed, 349 insertions(+) create mode 100644 drivers/nvdimm/nd_virtio.c create mode 100644 drivers/nvdimm/virtio_pmem.c create mode 100644 drivers/nvdimm/virtio_pmem.h create mode 100644 include/uapi/linux/virtio_pmem.h diff --git a/drivers/nvdimm/Makefile b/drivers/nvdimm/Makefile index 6f2a088afad6..cefe233e0b52 100644 --- a/drivers/nvdimm/Makefile +++ b/drivers/nvdimm/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_ND_BTT) += nd_btt.o obj-$(CONFIG_ND_BLK) += nd_blk.o obj-$(CONFIG_X86_PMEM_LEGACY) += nd_e820.o obj-$(CONFIG_OF_PMEM) += of_pmem.o +obj-$(CONFIG_VIRTIO_PMEM) += virtio_pmem.o nd_virtio.o nd_pmem-y := pmem.o diff --git a/drivers/nvdimm/nd_virtio.c b/drivers/nvdimm/nd_virtio.c new file mode 100644 index 000000000000..8645275c08c2 --- /dev/null +++ b/drivers/nvdimm/nd_virtio.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * virtio_pmem.c: Virtio pmem Driver + * + * Discovers persistent memory range information + * from host and provides a virtio based flushing + * interface. + */ +#include "virtio_pmem.h" +#include "nd.h" + + /* The interrupt handler */ +void virtio_pmem_host_ack(struct virtqueue *vq) +{ + struct virtio_pmem *vpmem = vq->vdev->priv; + struct virtio_pmem_request *req_data, *req_buf; + unsigned long flags; + unsigned int len; + + spin_lock_irqsave(&vpmem->pmem_lock, flags); + while ((req_data = virtqueue_get_buf(vq, &len)) != NULL) { + req_data->done = true; + wake_up(&req_data->host_acked); + + if (!list_empty(&vpmem->req_list)) { + req_buf = list_first_entry(&vpmem->req_list, + struct virtio_pmem_request, list); + req_buf->wq_buf_avail = true; + wake_up(&req_buf->wq_buf); + list_del(&req_buf->list); + } + } + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); +} +EXPORT_SYMBOL_GPL(virtio_pmem_host_ack); + + /* The request submission function */ +static int virtio_pmem_flush(struct nd_region *nd_region) +{ + struct virtio_device *vdev = nd_region->provider_data; + struct virtio_pmem *vpmem = vdev->priv; + struct virtio_pmem_request *req_data; + struct scatterlist *sgs[2], sg, ret; + unsigned long flags; + int err, err1; + + might_sleep(); + req_data = kmalloc(sizeof(*req_data), GFP_KERNEL); + if (!req_data) + return -ENOMEM; + + req_data->done = false; + init_waitqueue_head(&req_data->host_acked); + init_waitqueue_head(&req_data->wq_buf); + INIT_LIST_HEAD(&req_data->list); + req_data->req.type = cpu_to_virtio32(vdev, VIRTIO_PMEM_REQ_TYPE_FLUSH); + sg_init_one(&sg, &req_data->req, sizeof(req_data->req)); + sgs[0] = &sg; + sg_init_one(&ret, &req_data->resp.ret, sizeof(req_data->resp)); + sgs[1] = &ret; + + spin_lock_irqsave(&vpmem->pmem_lock, flags); + /* + * If virtqueue_add_sgs returns -ENOSPC then req_vq virtual + * queue does not have free descriptor. We add the request + * to req_list and wait for host_ack to wake us up when free + * slots are available. + */ + while ((err = virtqueue_add_sgs(vpmem->req_vq, sgs, 1, 1, req_data, + GFP_ATOMIC)) == -ENOSPC) { + + dev_info(&vdev->dev, "failed to send command to virtio pmem device, no free slots in the virtqueue\n"); + req_data->wq_buf_avail = false; + list_add_tail(&req_data->list, &vpmem->req_list); + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); + + /* A host response results in "host_ack" getting called */ + wait_event(req_data->wq_buf, req_data->wq_buf_avail); + spin_lock_irqsave(&vpmem->pmem_lock, flags); + } + err1 = virtqueue_kick(vpmem->req_vq); + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); + /* + * virtqueue_add_sgs failed with error different than -ENOSPC, we can't + * do anything about that. + */ + if (err || !err1) { + dev_info(&vdev->dev, "failed to send command to virtio pmem device\n"); + err = -EIO; + } else { + /* A host repsonse results in "host_ack" getting called */ + wait_event(req_data->host_acked, req_data->done); + err = virtio32_to_cpu(vdev, req_data->resp.ret); + } + + kfree(req_data); + return err; +}; + +/* The asynchronous flush callback function */ +int async_pmem_flush(struct nd_region *nd_region, struct bio *bio) +{ + /* + * Create child bio for asynchronous flush and chain with + * parent bio. Otherwise directly call nd_region flush. + */ + if (bio && bio->bi_iter.bi_sector != -1) { + struct bio *child = bio_alloc(GFP_ATOMIC, 0); + + if (!child) + return -ENOMEM; + bio_copy_dev(child, bio); + child->bi_opf = REQ_PREFLUSH; + child->bi_iter.bi_sector = -1; + bio_chain(child, bio); + submit_bio(child); + return 0; + } + if (virtio_pmem_flush(nd_region)) + return -EIO; + + return 0; +}; +EXPORT_SYMBOL_GPL(async_pmem_flush); +MODULE_LICENSE("GPL"); diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c new file mode 100644 index 000000000000..5e3d07b47e0c --- /dev/null +++ b/drivers/nvdimm/virtio_pmem.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * virtio_pmem.c: Virtio pmem Driver + * + * Discovers persistent memory range information + * from host and registers the virtual pmem device + * with libnvdimm core. + */ +#include "virtio_pmem.h" +#include "nd.h" + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_PMEM, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + + /* Initialize virt queue */ +static int init_vq(struct virtio_pmem *vpmem) +{ + /* single vq */ + vpmem->req_vq = virtio_find_single_vq(vpmem->vdev, + virtio_pmem_host_ack, "flush_queue"); + if (IS_ERR(vpmem->req_vq)) + return PTR_ERR(vpmem->req_vq); + + spin_lock_init(&vpmem->pmem_lock); + INIT_LIST_HEAD(&vpmem->req_list); + + return 0; +}; + +static int virtio_pmem_probe(struct virtio_device *vdev) +{ + struct nd_region_desc ndr_desc = {}; + int nid = dev_to_node(&vdev->dev); + struct nd_region *nd_region; + struct virtio_pmem *vpmem; + struct resource res; + int err = 0; + + if (!vdev->config->get) { + dev_err(&vdev->dev, "%s failure: config access disabled\n", + __func__); + return -EINVAL; + } + + vpmem = devm_kzalloc(&vdev->dev, sizeof(*vpmem), GFP_KERNEL); + if (!vpmem) { + err = -ENOMEM; + goto out_err; + } + + vpmem->vdev = vdev; + vdev->priv = vpmem; + err = init_vq(vpmem); + if (err) { + dev_err(&vdev->dev, "failed to initialize virtio pmem vq's\n"); + goto out_err; + } + + virtio_cread(vpmem->vdev, struct virtio_pmem_config, + start, &vpmem->start); + virtio_cread(vpmem->vdev, struct virtio_pmem_config, + size, &vpmem->size); + + res.start = vpmem->start; + res.end = vpmem->start + vpmem->size - 1; + vpmem->nd_desc.provider_name = "virtio-pmem"; + vpmem->nd_desc.module = THIS_MODULE; + + vpmem->nvdimm_bus = nvdimm_bus_register(&vdev->dev, + &vpmem->nd_desc); + if (!vpmem->nvdimm_bus) { + dev_err(&vdev->dev, "failed to register device with nvdimm_bus\n"); + err = -ENXIO; + goto out_vq; + } + + dev_set_drvdata(&vdev->dev, vpmem->nvdimm_bus); + + ndr_desc.res = &res; + ndr_desc.numa_node = nid; + ndr_desc.flush = async_pmem_flush; + set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); + set_bit(ND_REGION_ASYNC, &ndr_desc.flags); + nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc); + if (!nd_region) { + dev_err(&vdev->dev, "failed to create nvdimm region\n"); + err = -ENXIO; + goto out_nd; + } + nd_region->provider_data = dev_to_virtio(nd_region->dev.parent->parent); + return 0; +out_nd: + nvdimm_bus_unregister(vpmem->nvdimm_bus); +out_vq: + vdev->config->del_vqs(vdev); +out_err: + return err; +} + +static void virtio_pmem_remove(struct virtio_device *vdev) +{ + struct nvdimm_bus *nvdimm_bus = dev_get_drvdata(&vdev->dev); + + nvdimm_bus_unregister(nvdimm_bus); + vdev->config->del_vqs(vdev); + vdev->config->reset(vdev); +} + +static struct virtio_driver virtio_pmem_driver = { + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .probe = virtio_pmem_probe, + .remove = virtio_pmem_remove, +}; + +module_virtio_driver(virtio_pmem_driver); +MODULE_DEVICE_TABLE(virtio, id_table); +MODULE_DESCRIPTION("Virtio pmem driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/nvdimm/virtio_pmem.h b/drivers/nvdimm/virtio_pmem.h new file mode 100644 index 000000000000..0dddefe594c4 --- /dev/null +++ b/drivers/nvdimm/virtio_pmem.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * virtio_pmem.h: virtio pmem Driver + * + * Discovers persistent memory range information + * from host and provides a virtio based flushing + * interface. + **/ + +#ifndef _LINUX_VIRTIO_PMEM_H +#define _LINUX_VIRTIO_PMEM_H + +#include +#include +#include +#include + +struct virtio_pmem_request { + struct virtio_pmem_req req; + struct virtio_pmem_resp resp; + + /* Wait queue to process deferred work after ack from host */ + wait_queue_head_t host_acked; + bool done; + + /* Wait queue to process deferred work after virt queue buffer avail */ + wait_queue_head_t wq_buf; + bool wq_buf_avail; + struct list_head list; +}; + +struct virtio_pmem { + struct virtio_device *vdev; + + /* Virtio pmem request queue */ + struct virtqueue *req_vq; + + /* nvdimm bus registers virtio pmem device */ + struct nvdimm_bus *nvdimm_bus; + struct nvdimm_bus_descriptor nd_desc; + + /* List to store deferred work if virtqueue is full */ + struct list_head req_list; + + /* Synchronize virtqueue data */ + spinlock_t pmem_lock; + + /* Memory region information */ + __u64 start; + __u64 size; +}; + +void virtio_pmem_host_ack(struct virtqueue *vq); +int async_pmem_flush(struct nd_region *nd_region, struct bio *bio); +#endif diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 023fc3bc01c6..078615cf2afc 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -43,6 +43,17 @@ config VIRTIO_PCI_LEGACY If unsure, say Y. +config VIRTIO_PMEM + tristate "Support for virtio pmem driver" + depends on VIRTIO + depends on LIBNVDIMM + help + This driver provides access to virtio-pmem devices, storage devices + that are mapped into the physical address space - similar to NVDIMMs + - with a virtio-based flushing interface. + + If unsure, say Y. + config VIRTIO_BALLOON tristate "Virtio balloon driver" depends on VIRTIO diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h index 6d5c3b2d4f4d..32b2f94d1f58 100644 --- a/include/uapi/linux/virtio_ids.h +++ b/include/uapi/linux/virtio_ids.h @@ -43,5 +43,6 @@ #define VIRTIO_ID_INPUT 18 /* virtio input */ #define VIRTIO_ID_VSOCK 19 /* virtio vsock transport */ #define VIRTIO_ID_CRYPTO 20 /* virtio crypto */ +#define VIRTIO_ID_PMEM 27 /* virtio pmem */ #endif /* _LINUX_VIRTIO_IDS_H */ diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h new file mode 100644 index 000000000000..efcd72f2d20d --- /dev/null +++ b/include/uapi/linux/virtio_pmem.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ +/* + * Definitions for virtio-pmem devices. + * + * Copyright (C) 2019 Red Hat, Inc. + * + * Author(s): Pankaj Gupta + */ + +#ifndef _UAPI_LINUX_VIRTIO_PMEM_H +#define _UAPI_LINUX_VIRTIO_PMEM_H + +#include +#include +#include + +struct virtio_pmem_config { + __u64 start; + __u64 size; +}; + +#define VIRTIO_PMEM_REQ_TYPE_FLUSH 0 + +struct virtio_pmem_resp { + /* Host return status corresponding to flush request */ + __u32 ret; +}; + +struct virtio_pmem_req { + /* command type */ + __u32 type; +}; + +#endif From fefc1d97fa4b5e016bbe15447dc3edcd9e1bcb9f Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:24 +0530 Subject: [PATCH 4/9] libnvdimm: add dax_dev sync flag This patch adds 'DAXDEV_SYNC' flag which is set for nd_region doing synchronous flush. This later is used to disable MAP_SYNC functionality for ext4 & xfs filesystem for devices don't support synchronous flush. Signed-off-by: Pankaj Gupta Signed-off-by: Dan Williams --- drivers/dax/bus.c | 2 +- drivers/dax/super.c | 19 ++++++++++++++++++- drivers/md/dm.c | 3 ++- drivers/nvdimm/pmem.c | 5 ++++- drivers/nvdimm/region_devs.c | 7 +++++++ drivers/s390/block/dcssblk.c | 2 +- include/linux/dax.h | 24 ++++++++++++++++++++++-- include/linux/libnvdimm.h | 1 + 8 files changed, 56 insertions(+), 7 deletions(-) diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 2109cfe80219..5f184e751c82 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -388,7 +388,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, * No 'host' or dax_operations since there is no access to this * device outside of mmap of the resulting character device. */ - dax_dev = alloc_dax(dev_dax, NULL, NULL); + dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC); if (!dax_dev) goto err; diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 4e5ae7e8b557..8ab12068eea3 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -195,6 +195,8 @@ enum dax_device_flags { DAXDEV_ALIVE, /* gate whether dax_flush() calls the low level flush routine */ DAXDEV_WRITE_CACHE, + /* flag to check if device supports synchronous flush */ + DAXDEV_SYNC, }; /** @@ -372,6 +374,18 @@ bool dax_write_cache_enabled(struct dax_device *dax_dev) } EXPORT_SYMBOL_GPL(dax_write_cache_enabled); +bool __dax_synchronous(struct dax_device *dax_dev) +{ + return test_bit(DAXDEV_SYNC, &dax_dev->flags); +} +EXPORT_SYMBOL_GPL(__dax_synchronous); + +void __set_dax_synchronous(struct dax_device *dax_dev) +{ + set_bit(DAXDEV_SYNC, &dax_dev->flags); +} +EXPORT_SYMBOL_GPL(__set_dax_synchronous); + bool dax_alive(struct dax_device *dax_dev) { lockdep_assert_held(&dax_srcu); @@ -526,7 +540,7 @@ static void dax_add_host(struct dax_device *dax_dev, const char *host) } struct dax_device *alloc_dax(void *private, const char *__host, - const struct dax_operations *ops) + const struct dax_operations *ops, unsigned long flags) { struct dax_device *dax_dev; const char *host; @@ -549,6 +563,9 @@ struct dax_device *alloc_dax(void *private, const char *__host, dax_add_host(dax_dev, host); dax_dev->ops = ops; dax_dev->private = private; + if (flags & DAXDEV_F_SYNC) + set_dax_synchronous(dax_dev); + return dax_dev; err_dev: diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 5475081dcbd6..b1caa7188209 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1991,7 +1991,8 @@ static struct mapped_device *alloc_dev(int minor) sprintf(md->disk->disk_name, "dm-%d", minor); if (IS_ENABLED(CONFIG_DAX_DRIVER)) { - md->dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); + md->dax_dev = alloc_dax(md, md->disk->disk_name, + &dm_dax_ops, 0); if (!md->dax_dev) goto bad; } diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 223da63d1bd7..8be868e2a18b 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -376,6 +376,7 @@ static int pmem_attach_disk(struct device *dev, struct gendisk *disk; void *addr; int rc; + unsigned long flags = 0UL; pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL); if (!pmem) @@ -474,7 +475,9 @@ static int pmem_attach_disk(struct device *dev, nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res); disk->bb = &pmem->bb; - dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops); + if (is_nvdimm_sync(nd_region)) + flags = DAXDEV_F_SYNC; + dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags); if (!dax_dev) { put_disk(disk); return -ENOMEM; diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index eca2e62af134..56f2227f192a 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -1211,6 +1211,13 @@ int nvdimm_has_cache(struct nd_region *nd_region) } EXPORT_SYMBOL_GPL(nvdimm_has_cache); +bool is_nvdimm_sync(struct nd_region *nd_region) +{ + return is_nd_pmem(&nd_region->dev) && + !test_bit(ND_REGION_ASYNC, &nd_region->flags); +} +EXPORT_SYMBOL_GPL(is_nvdimm_sync); + struct conflict_context { struct nd_region *nd_region; resource_size_t start, size; diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index d04d4378ca50..63502ca537eb 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -679,7 +679,7 @@ dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char goto put_dev; dev_info->dax_dev = alloc_dax(dev_info, dev_info->gd->disk_name, - &dcssblk_dax_ops); + &dcssblk_dax_ops, DAXDEV_F_SYNC); if (!dev_info->dax_dev) { rc = -ENOMEM; goto put_dev; diff --git a/include/linux/dax.h b/include/linux/dax.h index becaea5f4488..8b535bc4526f 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -7,6 +7,9 @@ #include #include +/* Flag for synchronous flush */ +#define DAXDEV_F_SYNC (1UL << 0) + typedef unsigned long dax_entry_t; struct iomap_ops; @@ -38,18 +41,28 @@ extern struct attribute_group dax_attribute_group; #if IS_ENABLED(CONFIG_DAX) struct dax_device *dax_get_by_host(const char *host); struct dax_device *alloc_dax(void *private, const char *host, - const struct dax_operations *ops); + const struct dax_operations *ops, unsigned long flags); void put_dax(struct dax_device *dax_dev); void kill_dax(struct dax_device *dax_dev); void dax_write_cache(struct dax_device *dax_dev, bool wc); bool dax_write_cache_enabled(struct dax_device *dax_dev); +bool __dax_synchronous(struct dax_device *dax_dev); +static inline bool dax_synchronous(struct dax_device *dax_dev) +{ + return __dax_synchronous(dax_dev); +} +void __set_dax_synchronous(struct dax_device *dax_dev); +static inline void set_dax_synchronous(struct dax_device *dax_dev) +{ + __set_dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { return NULL; } static inline struct dax_device *alloc_dax(void *private, const char *host, - const struct dax_operations *ops) + const struct dax_operations *ops, unsigned long flags) { /* * Callers should check IS_ENABLED(CONFIG_DAX) to know if this @@ -70,6 +83,13 @@ static inline bool dax_write_cache_enabled(struct dax_device *dax_dev) { return false; } +static inline bool dax_synchronous(struct dax_device *dax_dev) +{ + return true; +} +static inline void set_dax_synchronous(struct dax_device *dax_dev) +{ +} #endif struct writeback_control; diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index e13100f424c8..7a64b3ddb408 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -263,6 +263,7 @@ int generic_nvdimm_flush(struct nd_region *nd_region); int nvdimm_has_flush(struct nd_region *nd_region); int nvdimm_has_cache(struct nd_region *nd_region); int nvdimm_in_overwrite(struct nvdimm *nvdimm); +bool is_nvdimm_sync(struct nd_region *nd_region); static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc) From 2e9ee0955d3c2d3db56aa02ba6f948ba35d5e9c1 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:25 +0530 Subject: [PATCH 5/9] dm: enable synchronous dax This patch sets dax device 'DAXDEV_SYNC' flag if all the target devices of device mapper support synchrononous DAX. If device mapper consists of both synchronous and asynchronous dax devices, we don't set 'DAXDEV_SYNC' flag. 'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn' as argument so that the callers can pass the appropriate functions. Suggested-by: Mike Snitzer Signed-off-by: Pankaj Gupta Reviewed-by: Mike Snitzer Signed-off-by: Dan Williams --- drivers/md/dm-table.c | 24 ++++++++++++++++++------ drivers/md/dm.c | 2 +- drivers/md/dm.h | 5 ++++- 3 files changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 350cf0451456..81c55304c4fa 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -881,7 +881,7 @@ void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type) EXPORT_SYMBOL_GPL(dm_table_set_type); /* validate the dax capability of the target device span */ -static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, +int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { int blocksize = *(int *) data; @@ -890,7 +890,15 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, start, len); } -bool dm_table_supports_dax(struct dm_table *t, int blocksize) +/* Check devices support synchronous DAX */ +static int device_synchronous(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + return dax_synchronous(dev->dax_dev); +} + +bool dm_table_supports_dax(struct dm_table *t, + iterate_devices_callout_fn iterate_fn, int *blocksize) { struct dm_target *ti; unsigned i; @@ -903,8 +911,7 @@ bool dm_table_supports_dax(struct dm_table *t, int blocksize) return false; if (!ti->type->iterate_devices || - !ti->type->iterate_devices(ti, device_supports_dax, - &blocksize)) + !ti->type->iterate_devices(ti, iterate_fn, blocksize)) return false; } @@ -940,6 +947,7 @@ static int dm_table_determine_type(struct dm_table *t) struct dm_target *tgt; struct list_head *devices = dm_table_get_devices(t); enum dm_queue_mode live_md_type = dm_get_md_type(t->md); + int page_size = PAGE_SIZE; if (t->type != DM_TYPE_NONE) { /* target already set the table's type */ @@ -984,7 +992,7 @@ static int dm_table_determine_type(struct dm_table *t) verify_bio_based: /* We must use this table as bio-based */ t->type = DM_TYPE_BIO_BASED; - if (dm_table_supports_dax(t, PAGE_SIZE) || + if (dm_table_supports_dax(t, device_supports_dax, &page_size) || (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) { t->type = DM_TYPE_DAX_BIO_BASED; } else { @@ -1883,6 +1891,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, struct queue_limits *limits) { bool wc = false, fua = false; + int page_size = PAGE_SIZE; /* * Copy table's limits to the DM device's request_queue @@ -1910,8 +1919,11 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, } blk_queue_write_cache(q, wc, fua); - if (dm_table_supports_dax(t, PAGE_SIZE)) + if (dm_table_supports_dax(t, device_supports_dax, &page_size)) { blk_queue_flag_set(QUEUE_FLAG_DAX, q); + if (dm_table_supports_dax(t, device_synchronous, NULL)) + set_dax_synchronous(t->md->dax_dev); + } else blk_queue_flag_clear(QUEUE_FLAG_DAX, q); diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b1caa7188209..b92c42a72ad4 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1119,7 +1119,7 @@ static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bd if (!map) return false; - ret = dm_table_supports_dax(map, blocksize); + ret = dm_table_supports_dax(map, device_supports_dax, &blocksize); dm_put_live_table(md, srcu_idx); diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 17e3db54404c..0475673337f3 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -72,7 +72,10 @@ bool dm_table_bio_based(struct dm_table *t); bool dm_table_request_based(struct dm_table *t); void dm_table_free_md_mempools(struct dm_table *t); struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t); -bool dm_table_supports_dax(struct dm_table *t, int blocksize); +bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn, + int *blocksize); +int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data); void dm_lock_md_type(struct mapped_device *md); void dm_unlock_md_type(struct mapped_device *md); From 32de1484648a837db5dea0a7007fe7136804e392 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:26 +0530 Subject: [PATCH 6/9] dax: check synchronous mapping is supported This patch introduces 'daxdev_mapping_supported' helper which checks if 'MAP_SYNC' is supported with filesystem mapping. It also checks if corresponding dax_device is synchronous. Virtio pmem device is asynchronous and does not not support VM_SYNC. Suggested-by: Jan Kara Signed-off-by: Pankaj Gupta Reviewed-by: Jan Kara Signed-off-by: Dan Williams --- include/linux/dax.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/include/linux/dax.h b/include/linux/dax.h index 8b535bc4526f..9bd8528bd305 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -56,6 +56,18 @@ static inline void set_dax_synchronous(struct dax_device *dax_dev) { __set_dax_synchronous(dax_dev); } +/* + * Check if given mapping is supported by the file / underlying device. + */ +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + if (!(vma->vm_flags & VM_SYNC)) + return true; + if (!IS_DAX(file_inode(vma->vm_file))) + return false; + return dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { @@ -90,6 +102,11 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) static inline void set_dax_synchronous(struct dax_device *dax_dev) { } +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + return !(vma->vm_flags & VM_SYNC); +} #endif struct writeback_control; From e46bfc3f03d7894c0eb47c7d754c38bafe39e197 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:27 +0530 Subject: [PATCH 7/9] ext4: disable map_sync for async flush Dont support 'MAP_SYNC' with non-DAX files and DAX files with asynchronous dax_device. Virtio pmem provides asynchronous host page cache flush mechanism. We don't support 'MAP_SYNC' with virtio pmem and ext4. Signed-off-by: Pankaj Gupta Reviewed-by: Jan Kara Signed-off-by: Dan Williams --- fs/ext4/file.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 2c5baa5e8291..4feeecae8db6 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -367,15 +367,17 @@ static const struct vm_operations_struct ext4_file_vm_ops = { static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) { struct inode *inode = file->f_mapping->host; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + struct dax_device *dax_dev = sbi->s_daxdev; - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(sbi))) return -EIO; /* - * We don't support synchronous mappings for non-DAX files. At least - * until someone comes with a sensible use case. + * We don't support synchronous mappings for non-DAX files and + * for DAX files if underneath dax_device is not synchronous. */ - if (!IS_DAX(file_inode(file)) && (vma->vm_flags & VM_SYNC)) + if (!daxdev_mapping_supported(vma, dax_dev)) return -EOPNOTSUPP; file_accessed(file); From b21fec414095d966789581c1466fb2f55de33bfe Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:28 +0530 Subject: [PATCH 8/9] xfs: disable map_sync for async flush Dont support 'MAP_SYNC' with non-DAX files and DAX files with asynchronous dax_device. Virtio pmem provides asynchronous host page cache flush mechanism. We don't support 'MAP_SYNC' with virtio pmem and xfs. Signed-off-by: Pankaj Gupta Reviewed-by: Darrick J. Wong Signed-off-by: Dan Williams --- fs/xfs/xfs_file.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 76748255f843..a06af58af475 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1203,11 +1203,14 @@ xfs_file_mmap( struct file *filp, struct vm_area_struct *vma) { + struct dax_device *dax_dev; + + dax_dev = xfs_find_daxdev_for_inode(file_inode(filp)); /* - * We don't support synchronous mappings for non-DAX files. At least - * until someone comes with a sensible use case. + * We don't support synchronous mappings for non-DAX files and + * for DAX files if underneath dax_device is not synchronous. */ - if (!IS_DAX(file_inode(filp)) && (vma->vm_flags & VM_SYNC)) + if (!daxdev_mapping_supported(vma, dax_dev)) return -EOPNOTSUPP; file_accessed(filp); From 8c2e408e73f735d2e6e8b43f9b038c9abb082939 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 12 Jul 2019 10:46:10 +0530 Subject: [PATCH 9/9] virtio_pmem: fix sparse warning This patch fixes below sparse warning related to __virtio type in virtio pmem driver. This is reported by Intel test bot on linux-next tree. nd_virtio.c:56:28: warning: incorrect type in assignment (different base types) nd_virtio.c:56:28: expected unsigned int [unsigned] [usertype] type nd_virtio.c:56:28: got restricted __virtio32 nd_virtio.c:93:59: warning: incorrect type in argument 2 (different base types) nd_virtio.c:93:59: expected restricted __virtio32 [usertype] val nd_virtio.c:93:59: got unsigned int [unsigned] [usertype] ret Reported-by: kbuild test robot Signed-off-by: Pankaj Gupta Acked-by: Michael S. Tsirkin Signed-off-by: Dan Williams --- drivers/nvdimm/nd_virtio.c | 4 ++-- include/uapi/linux/virtio_pmem.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/nd_virtio.c b/drivers/nvdimm/nd_virtio.c index 8645275c08c2..10351d5b49fa 100644 --- a/drivers/nvdimm/nd_virtio.c +++ b/drivers/nvdimm/nd_virtio.c @@ -53,7 +53,7 @@ static int virtio_pmem_flush(struct nd_region *nd_region) init_waitqueue_head(&req_data->host_acked); init_waitqueue_head(&req_data->wq_buf); INIT_LIST_HEAD(&req_data->list); - req_data->req.type = cpu_to_virtio32(vdev, VIRTIO_PMEM_REQ_TYPE_FLUSH); + req_data->req.type = cpu_to_le32(VIRTIO_PMEM_REQ_TYPE_FLUSH); sg_init_one(&sg, &req_data->req, sizeof(req_data->req)); sgs[0] = &sg; sg_init_one(&ret, &req_data->resp.ret, sizeof(req_data->resp)); @@ -90,7 +90,7 @@ static int virtio_pmem_flush(struct nd_region *nd_region) } else { /* A host repsonse results in "host_ack" getting called */ wait_event(req_data->host_acked, req_data->done); - err = virtio32_to_cpu(vdev, req_data->resp.ret); + err = le32_to_cpu(req_data->resp.ret); } kfree(req_data); diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h index efcd72f2d20d..9a63ed6d062f 100644 --- a/include/uapi/linux/virtio_pmem.h +++ b/include/uapi/linux/virtio_pmem.h @@ -23,12 +23,12 @@ struct virtio_pmem_config { struct virtio_pmem_resp { /* Host return status corresponding to flush request */ - __u32 ret; + __le32 ret; }; struct virtio_pmem_req { /* command type */ - __u32 type; + __le32 type; }; #endif