*/
#include <linux/fs.h>
+#include <linux/dax.h>
+#include <linux/pci.h>
+#include <linux/pfn_t.h>
#include <linux/module.h>
#include <linux/virtio.h>
#include <linux/virtio_fs.h>
#include <linux/delay.h>
#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
#include <linux/highmem.h>
+#include <linux/uio.h>
#include "fuse_i.h"
/* List of virtio-fs device instances and a lock for the list. Also provides
VQ_REQUEST
};
+#define VQ_NAME_LEN 24
+
/* Per-virtqueue state */
struct virtio_fs_vq {
spinlock_t lock;
bool connected;
long in_flight;
struct completion in_flight_zero; /* No inflight requests */
- char name[24];
+ char name[VQ_NAME_LEN];
} ____cacheline_aligned_in_smp;
/* A virtio-fs device instance */
struct virtio_fs_vq *vqs;
unsigned int nvqs; /* number of virtqueues */
unsigned int num_request_queues; /* number of request queues */
+ struct dax_device *dax_dev;
+
+ /* DAX memory window where file contents are mapped */
+ void *window_kaddr;
+ phys_addr_t window_phys_addr;
+ size_t window_len;
};
struct virtio_fs_forget_req {
static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
struct fuse_req *req, bool in_flight);
+enum {
+ OPT_DAX,
+};
+
+static const struct fs_parameter_spec virtio_fs_parameters[] = {
+ fsparam_flag("dax", OPT_DAX),
+ {}
+};
+
+static int virtio_fs_parse_param(struct fs_context *fc,
+ struct fs_parameter *param)
+{
+ struct fs_parse_result result;
+ struct fuse_fs_context *ctx = fc->fs_private;
+ int opt;
+
+ opt = fs_parse(fc, virtio_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case OPT_DAX:
+ ctx->dax = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void virtio_fs_free_fc(struct fs_context *fc)
+{
+ struct fuse_fs_context *ctx = fc->fs_private;
+
+ kfree(ctx);
+}
+
static inline struct virtio_fs_vq *vq_to_fsvq(struct virtqueue *vq)
{
struct virtio_fs *fs = vq->vdev->priv;
schedule_work(&fsvq->done_work);
}
+static void virtio_fs_init_vq(struct virtio_fs_vq *fsvq, char *name,
+ int vq_type)
+{
+ strncpy(fsvq->name, name, VQ_NAME_LEN);
+ spin_lock_init(&fsvq->lock);
+ INIT_LIST_HEAD(&fsvq->queued_reqs);
+ INIT_LIST_HEAD(&fsvq->end_reqs);
+ init_completion(&fsvq->in_flight_zero);
+
+ if (vq_type == VQ_REQUEST) {
+ INIT_WORK(&fsvq->done_work, virtio_fs_requests_done_work);
+ INIT_DELAYED_WORK(&fsvq->dispatch_work,
+ virtio_fs_request_dispatch_work);
+ } else {
+ INIT_WORK(&fsvq->done_work, virtio_fs_hiprio_done_work);
+ INIT_DELAYED_WORK(&fsvq->dispatch_work,
+ virtio_fs_hiprio_dispatch_work);
+ }
+}
+
/* Initialize virtqueues */
static int virtio_fs_setup_vqs(struct virtio_device *vdev,
struct virtio_fs *fs)
if (fs->num_request_queues == 0)
return -EINVAL;
- fs->nvqs = 1 + fs->num_request_queues;
+ fs->nvqs = VQ_REQUEST + fs->num_request_queues;
fs->vqs = kcalloc(fs->nvqs, sizeof(fs->vqs[VQ_HIPRIO]), GFP_KERNEL);
if (!fs->vqs)
return -ENOMEM;
goto out;
}
+ /* Initialize the hiprio/forget request virtqueue */
callbacks[VQ_HIPRIO] = virtio_fs_vq_done;
- snprintf(fs->vqs[VQ_HIPRIO].name, sizeof(fs->vqs[VQ_HIPRIO].name),
- "hiprio");
+ virtio_fs_init_vq(&fs->vqs[VQ_HIPRIO], "hiprio", VQ_HIPRIO);
names[VQ_HIPRIO] = fs->vqs[VQ_HIPRIO].name;
- INIT_WORK(&fs->vqs[VQ_HIPRIO].done_work, virtio_fs_hiprio_done_work);
- INIT_LIST_HEAD(&fs->vqs[VQ_HIPRIO].queued_reqs);
- INIT_LIST_HEAD(&fs->vqs[VQ_HIPRIO].end_reqs);
- INIT_DELAYED_WORK(&fs->vqs[VQ_HIPRIO].dispatch_work,
- virtio_fs_hiprio_dispatch_work);
- init_completion(&fs->vqs[VQ_HIPRIO].in_flight_zero);
- spin_lock_init(&fs->vqs[VQ_HIPRIO].lock);
/* Initialize the requests virtqueues */
for (i = VQ_REQUEST; i < fs->nvqs; i++) {
- spin_lock_init(&fs->vqs[i].lock);
- INIT_WORK(&fs->vqs[i].done_work, virtio_fs_requests_done_work);
- INIT_DELAYED_WORK(&fs->vqs[i].dispatch_work,
- virtio_fs_request_dispatch_work);
- INIT_LIST_HEAD(&fs->vqs[i].queued_reqs);
- INIT_LIST_HEAD(&fs->vqs[i].end_reqs);
- init_completion(&fs->vqs[i].in_flight_zero);
- snprintf(fs->vqs[i].name, sizeof(fs->vqs[i].name),
- "requests.%u", i - VQ_REQUEST);
+ char vq_name[VQ_NAME_LEN];
+
+ snprintf(vq_name, VQ_NAME_LEN, "requests.%u", i - VQ_REQUEST);
+ virtio_fs_init_vq(&fs->vqs[i], vq_name, VQ_REQUEST);
callbacks[i] = virtio_fs_vq_done;
names[i] = fs->vqs[i].name;
}
vdev->config->del_vqs(vdev);
}
+/* Map a window offset to a page frame number. The window offset will have
+ * been produced by .iomap_begin(), which maps a file offset to a window
+ * offset.
+ */
+static long virtio_fs_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
+ long nr_pages, void **kaddr, pfn_t *pfn)
+{
+ struct virtio_fs *fs = dax_get_private(dax_dev);
+ phys_addr_t offset = PFN_PHYS(pgoff);
+ size_t max_nr_pages = fs->window_len/PAGE_SIZE - pgoff;
+
+ if (kaddr)
+ *kaddr = fs->window_kaddr + offset;
+ if (pfn)
+ *pfn = phys_to_pfn_t(fs->window_phys_addr + offset,
+ PFN_DEV | PFN_MAP);
+ return nr_pages > max_nr_pages ? max_nr_pages : nr_pages;
+}
+
+static size_t virtio_fs_copy_from_iter(struct dax_device *dax_dev,
+ pgoff_t pgoff, void *addr,
+ size_t bytes, struct iov_iter *i)
+{
+ return copy_from_iter(addr, bytes, i);
+}
+
+static size_t virtio_fs_copy_to_iter(struct dax_device *dax_dev,
+ pgoff_t pgoff, void *addr,
+ size_t bytes, struct iov_iter *i)
+{
+ return copy_to_iter(addr, bytes, i);
+}
+
+static int virtio_fs_zero_page_range(struct dax_device *dax_dev,
+ pgoff_t pgoff, size_t nr_pages)
+{
+ long rc;
+ void *kaddr;
+
+ rc = dax_direct_access(dax_dev, pgoff, nr_pages, &kaddr, NULL);
+ if (rc < 0)
+ return rc;
+ memset(kaddr, 0, nr_pages << PAGE_SHIFT);
+ dax_flush(dax_dev, kaddr, nr_pages << PAGE_SHIFT);
+ return 0;
+}
+
+static const struct dax_operations virtio_fs_dax_ops = {
+ .direct_access = virtio_fs_direct_access,
+ .copy_from_iter = virtio_fs_copy_from_iter,
+ .copy_to_iter = virtio_fs_copy_to_iter,
+ .zero_page_range = virtio_fs_zero_page_range,
+};
+
+static void virtio_fs_cleanup_dax(void *data)
+{
+ struct dax_device *dax_dev = data;
+
+ kill_dax(dax_dev);
+ put_dax(dax_dev);
+}
+
+static int virtio_fs_setup_dax(struct virtio_device *vdev, struct virtio_fs *fs)
+{
+ struct virtio_shm_region cache_reg;
+ struct dev_pagemap *pgmap;
+ bool have_cache;
+
+ if (!IS_ENABLED(CONFIG_FUSE_DAX))
+ return 0;
+
+ /* Get cache region */
+ have_cache = virtio_get_shm_region(vdev, &cache_reg,
+ (u8)VIRTIO_FS_SHMCAP_ID_CACHE);
+ if (!have_cache) {
+ dev_notice(&vdev->dev, "%s: No cache capability\n", __func__);
+ return 0;
+ }
+
+ if (!devm_request_mem_region(&vdev->dev, cache_reg.addr, cache_reg.len,
+ dev_name(&vdev->dev))) {
+ dev_warn(&vdev->dev, "could not reserve region addr=0x%llx len=0x%llx\n",
+ cache_reg.addr, cache_reg.len);
+ return -EBUSY;
+ }
+
+ dev_notice(&vdev->dev, "Cache len: 0x%llx @ 0x%llx\n", cache_reg.len,
+ cache_reg.addr);
+
+ pgmap = devm_kzalloc(&vdev->dev, sizeof(*pgmap), GFP_KERNEL);
+ if (!pgmap)
+ return -ENOMEM;
+
+ pgmap->type = MEMORY_DEVICE_FS_DAX;
+
+ /* Ideally we would directly use the PCI BAR resource but
+ * devm_memremap_pages() wants its own copy in pgmap. So
+ * initialize a struct resource from scratch (only the start
+ * and end fields will be used).
+ */
+ pgmap->res = (struct resource){
+ .name = "virtio-fs dax window",
+ .start = (phys_addr_t) cache_reg.addr,
+ .end = (phys_addr_t) cache_reg.addr + cache_reg.len - 1,
+ };
+
+ fs->window_kaddr = devm_memremap_pages(&vdev->dev, pgmap);
+ if (IS_ERR(fs->window_kaddr))
+ return PTR_ERR(fs->window_kaddr);
+
+ fs->window_phys_addr = (phys_addr_t) cache_reg.addr;
+ fs->window_len = (phys_addr_t) cache_reg.len;
+
+ dev_dbg(&vdev->dev, "%s: window kaddr 0x%px phys_addr 0x%llx len 0x%llx\n",
+ __func__, fs->window_kaddr, cache_reg.addr, cache_reg.len);
+
+ fs->dax_dev = alloc_dax(fs, NULL, &virtio_fs_dax_ops, 0);
+ if (IS_ERR(fs->dax_dev))
+ return PTR_ERR(fs->dax_dev);
+
+ return devm_add_action_or_reset(&vdev->dev, virtio_fs_cleanup_dax,
+ fs->dax_dev);
+}
+
static int virtio_fs_probe(struct virtio_device *vdev)
{
struct virtio_fs *fs;
/* TODO vq affinity */
+ ret = virtio_fs_setup_dax(vdev, fs);
+ if (ret < 0)
+ goto out_vqs;
+
/* Bring the device online in case the filesystem is mounted and
* requests need to be sent before we return.
*/
.release = virtio_fs_fiq_release,
};
-static int virtio_fs_fill_super(struct super_block *sb)
+static inline void virtio_fs_ctx_set_defaults(struct fuse_fs_context *ctx)
+{
+ ctx->rootmode = S_IFDIR;
+ ctx->default_permissions = 1;
+ ctx->allow_other = 1;
+ ctx->max_read = UINT_MAX;
+ ctx->blksize = 512;
+ ctx->destroy = true;
+ ctx->no_control = true;
+ ctx->no_force_umount = true;
+}
+
+static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc)
{
struct fuse_conn *fc = get_fuse_conn_super(sb);
struct virtio_fs *fs = fc->iq.priv;
+ struct fuse_fs_context *ctx = fsc->fs_private;
unsigned int i;
int err;
- struct fuse_fs_context ctx = {
- .rootmode = S_IFDIR,
- .default_permissions = 1,
- .allow_other = 1,
- .max_read = UINT_MAX,
- .blksize = 512,
- .destroy = true,
- .no_control = true,
- .no_force_umount = true,
- .no_mount_options = true,
- };
+ virtio_fs_ctx_set_defaults(ctx);
mutex_lock(&virtio_fs_mutex);
/* After holding mutex, make sure virtiofs device is still there.
}
/* virtiofs allocates and installs its own fuse devices */
- ctx.fudptr = NULL;
- err = fuse_fill_super_common(sb, &ctx);
+ ctx->fudptr = NULL;
+ if (ctx->dax)
+ ctx->dax_dev = fs->dax_dev;
+ err = fuse_fill_super_common(sb, ctx);
if (err < 0)
goto err_free_fuse_devs;
return PTR_ERR(sb);
if (!sb->s_root) {
- err = virtio_fs_fill_super(sb);
+ err = virtio_fs_fill_super(sb, fsc);
if (err) {
deactivate_locked_super(sb);
return err;
}
static const struct fs_context_operations virtio_fs_context_ops = {
+ .free = virtio_fs_free_fc,
+ .parse_param = virtio_fs_parse_param,
.get_tree = virtio_fs_get_tree,
};
static int virtio_fs_init_fs_context(struct fs_context *fsc)
{
+ struct fuse_fs_context *ctx;
+
+ ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+ fsc->fs_private = ctx;
fsc->ops = &virtio_fs_context_ops;
return 0;
}
projects / linux-2.6-microblaze.git / blobdiff