On Wed, 21 Oct 2015, Ian Campbell wrote:
> In Xen 4.7 we are refactoring parts libxenctrl into a number of
> separate libraries which will provide backward and forward API and ABI
> compatiblity.
>
> One such library will be libxengnttab which provides access to grant
> tables.
>
> In preparation for this switch the compatibility layer in xen_common.h
> (which support building with older versions of Xen) to use what will
> be the new library API. This means that the gnttab shim will disappear
> for versions of Xen which include libxengnttab.
>
> To simplify things for the <= 4.0.0 support we wrap the int fd in a
> malloc(sizeof int) such that the handle is always a pointer. This
> leads to less typedef headaches and the need for
> XC_HANDLER_INITIAL_VALUE etc for these interfaces.
>
> Build tested with 4.0 and 4.5.
>
> Note that this patch does not add any support for actually using
> libxengnttab, it just adjusts the existing shims.
>
> Signed-off-by: Ian Campbell <ian.campb...@citrix.com>
The patch looks OK but doesn't apply cleanly to master, please rebase.
After fixing it up, it fails my 4.0 build test (I probably made a
mistake).
> v4: Ran checkpatch, fixed all errors
> Allocate correct size for handle (i.e. not size of the ptr)
> Rebase onto "xen_console: correctly cleanup primary console on
> teardown."
> ---
> hw/block/xen_disk.c | 38 ++++++++++++++++++++------------------
> hw/char/xen_console.c | 4 ++--
> hw/net/xen_nic.c | 16 ++++++++--------
> hw/xen/xen_backend.c | 10 +++++-----
> include/hw/xen/xen_backend.h | 2 +-
> include/hw/xen/xen_common.h | 42 ++++++++++++++++++++++++++++++++----------
> 6 files changed, 68 insertions(+), 44 deletions(-)
>
> diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c
> index 21842a0..15413f6 100644
> --- a/hw/block/xen_disk.c
> +++ b/hw/block/xen_disk.c
> @@ -172,11 +172,11 @@ static gint int_cmp(gconstpointer a, gconstpointer b,
> gpointer user_data)
> static void destroy_grant(gpointer pgnt)
> {
> PersistentGrant *grant = pgnt;
> - XenGnttab gnt = grant->blkdev->xendev.gnttabdev;
> + xengnttab_handle *gnt = grant->blkdev->xendev.gnttabdev;
>
> - if (xc_gnttab_munmap(gnt, grant->page, 1) != 0) {
> + if (xengnttab_munmap(gnt, grant->page, 1) != 0) {
> xen_be_printf(&grant->blkdev->xendev, 0,
> - "xc_gnttab_munmap failed: %s\n",
> + "xengnttab_munmap failed: %s\n",
> strerror(errno));
> }
> grant->blkdev->persistent_gnt_count--;
> @@ -189,11 +189,11 @@ static void remove_persistent_region(gpointer data,
> gpointer dev)
> {
> PersistentRegion *region = data;
> struct XenBlkDev *blkdev = dev;
> - XenGnttab gnt = blkdev->xendev.gnttabdev;
> + xengnttab_handle *gnt = blkdev->xendev.gnttabdev;
>
> - if (xc_gnttab_munmap(gnt, region->addr, region->num) != 0) {
> + if (xengnttab_munmap(gnt, region->addr, region->num) != 0) {
> xen_be_printf(&blkdev->xendev, 0,
> - "xc_gnttab_munmap region %p failed: %s\n",
> + "xengnttab_munmap region %p failed: %s\n",
> region->addr, strerror(errno));
> }
> xen_be_printf(&blkdev->xendev, 3,
> @@ -328,7 +328,7 @@ err:
>
> static void ioreq_unmap(struct ioreq *ioreq)
> {
> - XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
> + xengnttab_handle *gnt = ioreq->blkdev->xendev.gnttabdev;
> int i;
>
> if (ioreq->num_unmap == 0 || ioreq->mapped == 0) {
> @@ -338,8 +338,9 @@ static void ioreq_unmap(struct ioreq *ioreq)
> if (!ioreq->pages) {
> return;
> }
> - if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->num_unmap) != 0) {
> - xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap
> failed: %s\n",
> + if (xengnttab_munmap(gnt, ioreq->pages, ioreq->num_unmap) != 0) {
> + xen_be_printf(&ioreq->blkdev->xendev, 0,
> + "xengnttab_munmap failed: %s\n",
> strerror(errno));
> }
> ioreq->blkdev->cnt_map -= ioreq->num_unmap;
> @@ -349,8 +350,9 @@ static void ioreq_unmap(struct ioreq *ioreq)
> if (!ioreq->page[i]) {
> continue;
> }
> - if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
> - xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap
> failed: %s\n",
> + if (xengnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
> + xen_be_printf(&ioreq->blkdev->xendev, 0,
> + "xengnttab_munmap failed: %s\n",
> strerror(errno));
> }
> ioreq->blkdev->cnt_map--;
> @@ -362,7 +364,7 @@ static void ioreq_unmap(struct ioreq *ioreq)
>
> static int ioreq_map(struct ioreq *ioreq)
> {
> - XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
> + xengnttab_handle *gnt = ioreq->blkdev->xendev.gnttabdev;
> uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST];
> uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST];
> void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST];
> @@ -413,7 +415,7 @@ static int ioreq_map(struct ioreq *ioreq)
> }
>
> if (batch_maps && new_maps) {
> - ioreq->pages = xc_gnttab_map_grant_refs
> + ioreq->pages = xengnttab_map_grant_refs
> (gnt, new_maps, domids, refs, ioreq->prot);
> if (ioreq->pages == NULL) {
> xen_be_printf(&ioreq->blkdev->xendev, 0,
> @@ -429,7 +431,7 @@ static int ioreq_map(struct ioreq *ioreq)
> ioreq->blkdev->cnt_map += new_maps;
> } else if (new_maps) {
> for (i = 0; i < new_maps; i++) {
> - ioreq->page[i] = xc_gnttab_map_grant_ref
> + ioreq->page[i] = xengnttab_map_grant_ref
> (gnt, domids[i], refs[i], ioreq->prot);
> if (ioreq->page[i] == NULL) {
> xen_be_printf(&ioreq->blkdev->xendev, 0,
> @@ -762,9 +764,9 @@ static void blk_alloc(struct XenDevice *xendev)
> if (xen_mode != XEN_EMULATE) {
> batch_maps = 1;
> }
> - if (xc_gnttab_set_max_grants(xendev->gnttabdev,
> + if (xengnttab_set_max_grants(xendev->gnttabdev,
> MAX_GRANTS(max_requests, BLKIF_MAX_SEGMENTS_PER_REQUEST)) < 0) {
> - xen_be_printf(xendev, 0, "xc_gnttab_set_max_grants failed: %s\n",
> + xen_be_printf(xendev, 0, "xengnttab_set_max_grants failed: %s\n",
> strerror(errno));
> }
> }
> @@ -976,7 +978,7 @@ static int blk_connect(struct XenDevice *xendev)
> }
> }
>
> - blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
> + blkdev->sring = xengnttab_map_grant_ref(blkdev->xendev.gnttabdev,
> blkdev->xendev.dom,
> blkdev->ring_ref,
> PROT_READ | PROT_WRITE);
> @@ -1041,7 +1043,7 @@ static void blk_disconnect(struct XenDevice *xendev)
> xen_be_unbind_evtchn(&blkdev->xendev);
>
> if (blkdev->sring) {
> - xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
> + xengnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
> blkdev->cnt_map--;
> blkdev->sring = NULL;
> }
> diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
> index 63ade33..8c06c19 100644
> --- a/hw/char/xen_console.c
> +++ b/hw/char/xen_console.c
> @@ -233,7 +233,7 @@ static int con_initialise(struct XenDevice *xendev)
> PROT_READ|PROT_WRITE,
> con->ring_ref);
> } else {
> - con->sring = xc_gnttab_map_grant_ref(xendev->gnttabdev,
> con->xendev.dom,
> + con->sring = xengnttab_map_grant_ref(xendev->gnttabdev,
> con->xendev.dom,
> con->ring_ref,
> PROT_READ|PROT_WRITE);
> }
> @@ -275,7 +275,7 @@ static void con_disconnect(struct XenDevice *xendev)
> if (!xendev->dev) {
> munmap(con->sring, XC_PAGE_SIZE);
> } else {
> - xc_gnttab_munmap(xendev->gnttabdev, con->sring, 1);
> + xengnttab_munmap(xendev->gnttabdev, con->sring, 1);
> }
> con->sring = NULL;
> }
> diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
> index 63918ae..778de28 100644
> --- a/hw/net/xen_nic.c
> +++ b/hw/net/xen_nic.c
> @@ -169,7 +169,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
> (txreq.flags & NETTXF_more_data) ? "
> more_data" : "",
> (txreq.flags & NETTXF_extra_info) ? "
> extra_info" : "");
>
> - page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
> + page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
> netdev->xendev.dom,
> txreq.gref, PROT_READ);
> if (page == NULL) {
> @@ -191,7 +191,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
> qemu_send_packet(qemu_get_queue(netdev->nic),
> page + txreq.offset, txreq.size);
> }
> - xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
> + xengnttab_munmap(netdev->xendev.gnttabdev, page, 1);
> net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
> }
> if (!netdev->tx_work) {
> @@ -283,7 +283,7 @@ static ssize_t net_rx_packet(NetClientState *nc, const
> uint8_t *buf, size_t size
> memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
> netdev->rx_ring.req_cons = ++rc;
>
> - page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
> + page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
> netdev->xendev.dom,
> rxreq.gref, PROT_WRITE);
> if (page == NULL) {
> @@ -293,7 +293,7 @@ static ssize_t net_rx_packet(NetClientState *nc, const
> uint8_t *buf, size_t size
> return -1;
> }
> memcpy(page + NET_IP_ALIGN, buf, size);
> - xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
> + xengnttab_munmap(netdev->xendev.gnttabdev, page, 1);
> net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0);
>
> return size;
> @@ -366,11 +366,11 @@ static int net_connect(struct XenDevice *xendev)
> return -1;
> }
>
> - netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
> + netdev->txs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
> netdev->xendev.dom,
> netdev->tx_ring_ref,
> PROT_READ | PROT_WRITE);
> - netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
> + netdev->rxs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
> netdev->xendev.dom,
> netdev->rx_ring_ref,
> PROT_READ | PROT_WRITE);
> @@ -398,11 +398,11 @@ static void net_disconnect(struct XenDevice *xendev)
> xen_be_unbind_evtchn(&netdev->xendev);
>
> if (netdev->txs) {
> - xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
> + xengnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
> netdev->txs = NULL;
> }
> if (netdev->rxs) {
> - xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
> + xengnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
> netdev->rxs = NULL;
> }
> if (netdev->nic) {
> diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
> index 342ec9b..f988b95 100644
> --- a/hw/xen/xen_backend.c
> +++ b/hw/xen/xen_backend.c
> @@ -252,15 +252,15 @@ static struct XenDevice *xen_be_get_xendev(const char
> *type, int dom, int dev,
> fcntl(xenevtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
>
> if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
> - xendev->gnttabdev = xen_xc_gnttab_open(NULL, 0);
> - if (xendev->gnttabdev == XC_HANDLER_INITIAL_VALUE) {
> + xendev->gnttabdev = xengnttab_open(NULL, 0);
> + if (xendev->gnttabdev == NULL) {
> xen_be_printf(NULL, 0, "can't open gnttab device\n");
> xenevtchn_close(xendev->evtchndev);
> g_free(xendev);
> return NULL;
> }
> } else {
> - xendev->gnttabdev = XC_HANDLER_INITIAL_VALUE;
> + xendev->gnttabdev = NULL;
> }
>
> QTAILQ_INSERT_TAIL(&xendevs, xendev, next);
> @@ -309,8 +309,8 @@ static struct XenDevice *xen_be_del_xendev(int dom, int
> dev)
> if (xendev->evtchndev != NULL) {
> xenevtchn_close(xendev->evtchndev);
> }
> - if (xendev->gnttabdev != XC_HANDLER_INITIAL_VALUE) {
> - xc_gnttab_close(xendev->gnttabdev);
> + if (xendev->gnttabdev != NULL) {
> + xengnttab_close(xendev->gnttabdev);
> }
>
> QTAILQ_REMOVE(&xendevs, xendev, next);
> diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
> index a90314f..8e8857b 100644
> --- a/include/hw/xen/xen_backend.h
> +++ b/include/hw/xen/xen_backend.h
> @@ -47,7 +47,7 @@ struct XenDevice {
> int local_port;
>
> xenevtchn_handle *evtchndev;
> - XenGnttab gnttabdev;
> + xengnttab_handle *gnttabdev;
>
> struct XenDevOps *ops;
> QTAILQ_ENTRY(XenDevice) next;
> diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
> index 4dc2ee6..db62df4 100644
> --- a/include/hw/xen/xen_common.h
> +++ b/include/hw/xen/xen_common.h
> @@ -40,7 +40,7 @@ static inline void *xc_map_foreign_bulk(int xc_handle,
> uint32_t dom, int prot,
>
> typedef int XenXC;
> typedef int xenevtchn_handle;
> -typedef int XenGnttab;
> +typedef int xengnttab_handle;
>
> # define XC_INTERFACE_FMT "%i"
> # define XC_HANDLER_INITIAL_VALUE -1
> @@ -72,11 +72,31 @@ static inline int xenevtchn_close(xenevtchn_handle *h)
> #define xenevtchn_unmask(h, p) xc_evtchn_unmask(*h, p)
> #define xenevtchn_unbind(h, p) xc_evtchn_unmask(*h, p)
>
> -static inline XenGnttab xen_xc_gnttab_open(void *logger,
> - unsigned int open_flags)
> +static inline xengnttab_handle *xengnttab_open(void *logger,
> + unsigned int open_flags)
> {
> - return xc_gnttab_open();
> + xengnttab_handle *h = malloc(sizeof(*h));
> + if (!h) {
> + return NULL;
> + }
> + *h = xc_gnttab_open();
> + if (*h == -1) {
> + free(h);
> + h = NULL;
> + }
> + return h;
> }
> +static inline int xengnttab_close(xengnttab_handle *h)
> +{
> + int rc = xc_gnttab_close(*h);
> + free(h);
> + return rc;
> +}
> +#define xengnttab_set_max_grants(h, n) xc_gnttab_set_max_grants(*h, n)
> +#define xengnttab_map_grant_ref(h, d, r, p) xc_gnttab_map_grant_ref(*h, d,
> r, p)
> +#define xengnttab_map_grant_refs(h, c, d, r, p) \
> + xc_gnttab_map_grant_refs(*h, c, d, r, p)
> +#define xengnttab_munmap(h, a, n) xc_gnttab_munmap(*h, a, n)
>
> static inline XenXC xen_xc_interface_open(void *logger, void
> *dombuild_logger,
> unsigned int open_flags)
> @@ -130,7 +150,7 @@ static inline void xs_close(struct xs_handle *xsh)
>
> typedef xc_interface *XenXC;
> typedef xc_evtchn xenevtchn_handle;
> -typedef xc_gnttab *XenGnttab;
> +typedef xc_gnttab xengnttab_handle;
>
> # define XC_INTERFACE_FMT "%p"
> # define XC_HANDLER_INITIAL_VALUE NULL
> @@ -144,11 +164,13 @@ typedef xc_gnttab *XenGnttab;
> #define xenevtchn_unmask(h, p) xc_evtchn_unmask(h, p)
> #define xenevtchn_unbind(h, p) xc_evtchn_unbind(h, p)
>
> -static inline XenGnttab xen_xc_gnttab_open(void *logger,
> - unsigned int open_flags)
> -{
> - return xc_gnttab_open(logger, open_flags);
> -}
> +#define xengnttab_open(l, f) xc_gnttab_open(l, f)
> +#define xengnttab_close(h) xc_gnttab_close(h)
> +#define xengnttab_set_max_grants(h, n) xc_gnttab_set_max_grants(h, n)
> +#define xengnttab_map_grant_ref(h, d, r, p) xc_gnttab_map_grant_ref(h, d, r,
> p)
> +#define xengnttab_munmap(h, a, n) xc_gnttab_munmap(h, a, n)
> +#define xengnttab_map_grant_refs(h, c, d, r, p) \
> + xc_gnttab_map_grant_refs(h, c, d, r, p)
>
> static inline XenXC xen_xc_interface_open(void *logger, void
> *dombuild_logger,
> unsigned int open_flags)
> --
> 2.1.4
>
