On Wed, 14 Apr 2021 16:51:20 +0100 "Dr. David Alan Gilbert (git)" <[email protected]> wrote:
> From: "Dr. David Alan Gilbert" <[email protected]> > > The daemon may request that fd's be mapped into the virtio-fs cache > visible to the guest. > These mappings are triggered by commands sent over the slave fd > from the daemon. > > Signed-off-by: Dr. David Alan Gilbert <[email protected]> > --- > docs/interop/vhost-user.rst | 21 ++++++++ > hw/virtio/vhost-user-fs.c | 66 +++++++++++++++++++++++ > hw/virtio/vhost-user.c | 25 +++++++++ > include/hw/virtio/vhost-user-fs.h | 33 ++++++++++++ > subprojects/libvhost-user/libvhost-user.h | 2 + > 5 files changed, 147 insertions(+) > > diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst > index d6085f7045..09aee3565d 100644 > --- a/docs/interop/vhost-user.rst > +++ b/docs/interop/vhost-user.rst > @@ -1432,6 +1432,27 @@ Slave message types > > The state.num field is currently reserved and must be set to 0. > > +``VHOST_USER_SLAVE_FS_MAP`` > + :id: 6 > + :equivalent ioctl: N/A > + :slave payload: ``struct VhostUserFSSlaveMsg`` > + :master payload: N/A > + > + Requests that an fd, provided in the ancillary data, be mmapped > + into the virtio-fs cache; multiple chunks can be mapped in one > + command. > + A reply is generated indicating whether mapping succeeded. > + > +``VHOST_USER_SLAVE_FS_UNMAP`` > + :id: 7 > + :equivalent ioctl: N/A > + :slave payload: ``struct VhostUserFSSlaveMsg`` > + :master payload: N/A > + > + Requests that the range in the virtio-fs cache is unmapped; > + multiple chunks can be unmapped in one command. > + A reply is generated indicating whether unmapping succeeded. > + > .. _reply_ack: > > VHOST_USER_PROTOCOL_F_REPLY_ACK > diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c > index dd0a02aa99..169a146e72 100644 > --- a/hw/virtio/vhost-user-fs.c > +++ b/hw/virtio/vhost-user-fs.c > @@ -45,6 +45,72 @@ static const int user_feature_bits[] = { > #define DAX_WINDOW_PROT PROT_NONE > #endif > > +/* > + * The message apparently had 'received_size' bytes, check this > + * matches the count in the message. > + * > + * Returns true if the size matches. > + */ > +static bool check_slave_message_entries(const VhostUserFSSlaveMsg *sm, > + int received_size) > +{ > + int tmp; > + > + /* > + * VhostUserFSSlaveMsg consists of a body followed by 'n' entries, > + * (each VhostUserFSSlaveMsgEntry). There's a maximum of > + * VHOST_USER_FS_SLAVE_MAX_ENTRIES of these. > + */ > + if (received_size <= sizeof(VhostUserFSSlaveMsg)) { > + error_report("%s: Short VhostUserFSSlaveMsg size, %d", __func__, > + received_size); > + return false; > + } > + > + tmp = received_size - sizeof(VhostUserFSSlaveMsg); > + if (tmp % sizeof(VhostUserFSSlaveMsgEntry)) { > + error_report("%s: Non-multiple VhostUserFSSlaveMsg size, %d", > __func__, > + received_size); > + return false; > + } > + > + tmp /= sizeof(VhostUserFSSlaveMsgEntry); > + if (tmp != sm->count) { > + error_report("%s: VhostUserFSSlaveMsg count mismatch, %d count: %d", > + __func__, tmp, sm->count); > + return false; > + } > + > + if (sm->count > VHOST_USER_FS_SLAVE_MAX_ENTRIES) { > + error_report("%s: VhostUserFSSlaveMsg too many entries: %d", > + __func__, sm->count); > + return false; > + } > + return true; > +} > + > +uint64_t vhost_user_fs_slave_map(struct vhost_dev *dev, int message_size, > + VhostUserFSSlaveMsg *sm, int fd) > +{ > + if (!check_slave_message_entries(sm, message_size)) { > + return (uint64_t)-1; > + } > + > + /* TODO */ > + return (uint64_t)-1; > +} > + > +uint64_t vhost_user_fs_slave_unmap(struct vhost_dev *dev, int message_size, > + VhostUserFSSlaveMsg *sm) > +{ > + if (!check_slave_message_entries(sm, message_size)) { > + return (uint64_t)-1; > + } > + > + /* TODO */ > + return (uint64_t)-1; > +} > + > static void vuf_get_config(VirtIODevice *vdev, uint8_t *config) > { > VHostUserFS *fs = VHOST_USER_FS(vdev); > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index 3e4a25e108..ad9170f8dc 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -12,6 +12,7 @@ > #include "qapi/error.h" > #include "hw/virtio/vhost.h" > #include "hw/virtio/vhost-user.h" > +#include "hw/virtio/vhost-user-fs.h" > #include "hw/virtio/vhost-backend.h" > #include "hw/virtio/virtio.h" > #include "hw/virtio/virtio-net.h" > @@ -133,6 +134,10 @@ typedef enum VhostUserSlaveRequest { > VHOST_USER_SLAVE_IOTLB_MSG = 1, > VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2, > VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3, > + VHOST_USER_SLAVE_VRING_CALL = 4, > + VHOST_USER_SLAVE_VRING_ERR = 5, > + VHOST_USER_SLAVE_FS_MAP = 6, > + VHOST_USER_SLAVE_FS_UNMAP = 7, > VHOST_USER_SLAVE_MAX > } VhostUserSlaveRequest; > > @@ -205,6 +210,16 @@ typedef struct { > uint32_t size; /* the following payload size */ > } QEMU_PACKED VhostUserHeader; > > +/* > + * VhostUserFSSlaveMsg is special since it has a variable entry count, > + * but it does have a maximum, so make a type for that to fit in our union > + * for max size. > + */ > +typedef struct { > + VhostUserFSSlaveMsg fs; > + VhostUserFSSlaveMsgEntry entries[VHOST_USER_FS_SLAVE_MAX_ENTRIES]; > +} QEMU_PACKED VhostUserFSSlaveMsgMax; > + > typedef union { > #define VHOST_USER_VRING_IDX_MASK (0xff) > #define VHOST_USER_VRING_NOFD_MASK (0x1<<8) > @@ -219,6 +234,8 @@ typedef union { > VhostUserCryptoSession session; > VhostUserVringArea area; > VhostUserInflight inflight; > + VhostUserFSSlaveMsg fs; > + VhostUserFSSlaveMsg fs_max; /* Never actually used */ > } VhostUserPayload; > > typedef struct VhostUserMsg { > @@ -1538,6 +1555,14 @@ static gboolean slave_read(QIOChannel *ioc, > GIOCondition condition, > ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area, > fd ? fd[0] : -1); > break; > +#ifdef CONFIG_VHOST_USER_FS > + case VHOST_USER_SLAVE_FS_MAP: > + ret = vhost_user_fs_slave_map(dev, hdr.size, &payload.fs, fd[0]); Since the QIOChannel conversion, the array of fds is dynamically allocated by qio_channel_readv_full_all() when needed. You should do "fd ? fd[0] : -1" like for vhost_user_slave_handle_vring_host_notifier() just above. Same goes for patch 17 "DAX/unmap: virtiofsd: Add VHOST_USER_SLAVE_FS_IO". > + break; > + case VHOST_USER_SLAVE_FS_UNMAP: > + ret = vhost_user_fs_slave_unmap(dev, hdr.size, &payload.fs); > + break; > +#endif > default: > error_report("Received unexpected msg type: %d.", hdr.request); > ret = true; > diff --git a/include/hw/virtio/vhost-user-fs.h > b/include/hw/virtio/vhost-user-fs.h > index 04596799e3..0766f17548 100644 > --- a/include/hw/virtio/vhost-user-fs.h > +++ b/include/hw/virtio/vhost-user-fs.h > @@ -23,6 +23,33 @@ > #define TYPE_VHOST_USER_FS "vhost-user-fs-device" > OBJECT_DECLARE_SIMPLE_TYPE(VHostUserFS, VHOST_USER_FS) > > +/* Structures carried over the slave channel back to QEMU */ > +#define VHOST_USER_FS_SLAVE_MAX_ENTRIES 32 > + > +/* For the flags field of VhostUserFSSlaveMsg */ > +#define VHOST_USER_FS_FLAG_MAP_R (1u << 0) > +#define VHOST_USER_FS_FLAG_MAP_W (1u << 1) > + > +typedef struct { > + /* Offsets within the file being mapped */ > + uint64_t fd_offset; > + /* Offsets within the cache */ > + uint64_t c_offset; > + /* Lengths of sections */ > + uint64_t len; > + /* Flags, from VHOST_USER_FS_FLAG_* */ > + uint64_t flags; > +} VhostUserFSSlaveMsgEntry; > + > +typedef struct { > + /* Number of entries */ > + uint16_t count; > + /* Spare */ > + uint16_t align; > + > + VhostUserFSSlaveMsgEntry entries[]; > +} VhostUserFSSlaveMsg; > + > typedef struct { > CharBackend chardev; > char *tag; > @@ -46,4 +73,10 @@ struct VHostUserFS { > MemoryRegion cache; > }; > > +/* Callbacks from the vhost-user code for slave commands */ > +uint64_t vhost_user_fs_slave_map(struct vhost_dev *dev, int message_size, > + VhostUserFSSlaveMsg *sm, int fd); > +uint64_t vhost_user_fs_slave_unmap(struct vhost_dev *dev, int message_size, > + VhostUserFSSlaveMsg *sm); > + > #endif /* _QEMU_VHOST_USER_FS_H */ > diff --git a/subprojects/libvhost-user/libvhost-user.h > b/subprojects/libvhost-user/libvhost-user.h > index 70fc61171f..a98c5f5c11 100644 > --- a/subprojects/libvhost-user/libvhost-user.h > +++ b/subprojects/libvhost-user/libvhost-user.h > @@ -119,6 +119,8 @@ typedef enum VhostUserSlaveRequest { > VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3, > VHOST_USER_SLAVE_VRING_CALL = 4, > VHOST_USER_SLAVE_VRING_ERR = 5, > + VHOST_USER_SLAVE_FS_MAP = 6, > + VHOST_USER_SLAVE_FS_UNMAP = 7, > VHOST_USER_SLAVE_MAX > } VhostUserSlaveRequest; > _______________________________________________ Virtio-fs mailing list [email protected] https://listman.redhat.com/mailman/listinfo/virtio-fs
