From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
Add a cache BAR into which files will be directly mapped.
The size can be set with the cache-size= property, e.g.
-device vhost-user-fs-pci,chardev=char0,tag=myfs,cache-size=16G
The default is no cache.
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
with PPC fixes by:
Signed-off-by: Fabiano Rosas <faro...@linux.ibm.com>
---
hw/virtio/vhost-user-fs-pci.c | 25 ++++++++++++++++++++++++
hw/virtio/vhost-user-fs.c | 32 +++++++++++++++++++++++++++++++
include/hw/virtio/vhost-user-fs.h | 2 ++
3 files changed, 59 insertions(+)
diff --git a/hw/virtio/vhost-user-fs-pci.c b/hw/virtio/vhost-user-fs-pci.c
index 2ed8492b3f..0388e063c6 100644
--- a/hw/virtio/vhost-user-fs-pci.c
+++ b/hw/virtio/vhost-user-fs-pci.c
@@ -16,10 +16,14 @@
#include "hw/virtio/vhost-user-fs.h"
#include "virtio-pci.h"
#include "qom/object.h"
+#include "standard-headers/linux/virtio_fs.h"
+
+#define VIRTIO_FS_PCI_CACHE_BAR 2
struct VHostUserFSPCI {
VirtIOPCIProxy parent_obj;
VHostUserFS vdev;
+ MemoryRegion cachebar;
};
typedef struct VHostUserFSPCI VHostUserFSPCI;
@@ -39,6 +43,7 @@ static void vhost_user_fs_pci_realize(VirtIOPCIProxy
*vpci_dev, Error **errp)
{
VHostUserFSPCI *dev = VHOST_USER_FS_PCI(vpci_dev);
DeviceState *vdev = DEVICE(&dev->vdev);
+ uint64_t cachesize;
if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
/* Also reserve config change and hiprio queue vectors */
@@ -46,6 +51,26 @@ static void vhost_user_fs_pci_realize(VirtIOPCIProxy
*vpci_dev, Error **errp)
}
qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
+ cachesize = dev->vdev.conf.cache_size;
+
+ /*
+ * The bar starts with the data/DAX cache
+ * Others will be added later.
+ */
+ memory_region_init(&dev->cachebar, OBJECT(vpci_dev),
+ "vhost-fs-pci-cachebar", cachesize);
+ if (cachesize) {
+ memory_region_add_subregion(&dev->cachebar, 0, &dev->vdev.cache);
+ virtio_pci_add_shm_cap(vpci_dev, VIRTIO_FS_PCI_CACHE_BAR, 0, cachesize,
+ VIRTIO_FS_SHMCAP_ID_CACHE);
+ }
+
+ /* After 'realized' so the memory region exists */
+ pci_register_bar(&vpci_dev->pci_dev, VIRTIO_FS_PCI_CACHE_BAR,
+ PCI_BASE_ADDRESS_SPACE_MEMORY |
+ PCI_BASE_ADDRESS_MEM_PREFETCH |
+ PCI_BASE_ADDRESS_MEM_TYPE_64,
+ &dev->cachebar);
}
static void vhost_user_fs_pci_class_init(ObjectClass *klass, void *data)
diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
index ac4fc34b36..b077d8e705 100644
--- a/hw/virtio/vhost-user-fs.c
+++ b/hw/virtio/vhost-user-fs.c
@@ -24,6 +24,16 @@
#include "monitor/monitor.h"
#include "sysemu/sysemu.h"
+/*
+ * The powerpc kernel code expects the memory to be accessible during
+ * addition/removal.
+ */
+#if defined(TARGET_PPC64) && defined(CONFIG_LINUX)
+#define DAX_WINDOW_PROT PROT_READ
+#else
+#define DAX_WINDOW_PROT PROT_NONE
+#endif
+
static void vuf_get_config(VirtIODevice *vdev, uint8_t *config)
{
VHostUserFS *fs = VHOST_USER_FS(vdev);
@@ -163,6 +173,7 @@ static void vuf_device_realize(DeviceState *dev, Error
**errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
VHostUserFS *fs = VHOST_USER_FS(dev);
+ void *cache_ptr;
unsigned int i;
size_t len;
int ret;
@@ -202,6 +213,26 @@ static void vuf_device_realize(DeviceState *dev, Error
**errp)
VIRTQUEUE_MAX_SIZE);
return;
}
+ if (fs->conf.cache_size &&
+ (!is_power_of_2(fs->conf.cache_size) ||
+ fs->conf.cache_size < qemu_real_host_page_size)) {
+ error_setg(errp, "cache-size property must be a power of 2 "
+ "no smaller than the page size");
+ return;
+ }
+ if (fs->conf.cache_size) {
+ /* Anonymous, private memory is not counted as overcommit */
+ cache_ptr = mmap(NULL, fs->conf.cache_size, DAX_WINDOW_PROT,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (cache_ptr == MAP_FAILED) {
+ error_setg(errp, "Unable to mmap blank cache");
+ return;
+ }
+
+ memory_region_init_ram_ptr(&fs->cache, OBJECT(vdev),
+ "virtio-fs-cache",
+ fs->conf.cache_size, cache_ptr);
+ }
if (!vhost_user_init(&fs->vhost_user, &fs->conf.chardev, errp)) {
return;
@@ -277,6 +308,7 @@ static Property vuf_properties[] = {
DEFINE_PROP_UINT16("num-request-queues", VHostUserFS,
conf.num_request_queues, 1),
DEFINE_PROP_UINT16("queue-size", VHostUserFS, conf.queue_size, 128),
+ DEFINE_PROP_SIZE("cache-size", VHostUserFS, conf.cache_size, 0),
DEFINE_PROP_END_OF_LIST(),
};
diff --git a/include/hw/virtio/vhost-user-fs.h
b/include/hw/virtio/vhost-user-fs.h
index 0d62834c25..04596799e3 100644
--- a/include/hw/virtio/vhost-user-fs.h
+++ b/include/hw/virtio/vhost-user-fs.h
@@ -28,6 +28,7 @@ typedef struct {
char *tag;
uint16_t num_request_queues;
uint16_t queue_size;
+ uint64_t cache_size;
} VHostUserFSConf;
struct VHostUserFS {
@@ -42,6 +43,7 @@ struct VHostUserFS {
int32_t bootindex;
/*< public >*/
+ MemoryRegion cache;
};
#endif /* _QEMU_VHOST_USER_FS_H */
--
2.29.2
