The underlaying toolstack code to do the basic
operations when using the XEN_XSPLICE_op syscalls:
- upload the payload,
- get status of an payload,
- list all the payloads,
- apply, check, replace, and revert the payload.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
Signed-off-by: Ross Lagerwall <ross.lagerw...@citrix.com>
Acked-by: Wei Liu <wei.l...@citrix.com>
Reviewed-by: Andrew Cooper <andrew.coop...@citrix.com>
---
Cc: Ian Jackson <ian.jack...@eu.citrix.com>
Cc: Stefano Stabellini <sstabell...@kernel.org>
Cc: Wei Liu <wei.l...@citrix.com>
v2: Actually set zero for the _pad entries.
v3: Split status into state and error code.
Add REPLACE action.
- Use timeout and utilize pads.
- Update per Wei's review.
- Extra space slipped in, remove it
v4: Add Wei's review, update comment and Ack.
v7: Sprinkle errno=-EINVAL on all the 'if (!len)', etc checks.
Added Reviewed-by from Andrew.
---
---
tools/libxc/include/xenctrl.h | 62 ++++++++
tools/libxc/xc_misc.c | 355 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 417 insertions(+)
diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index f5a034a..a7937fa 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -2640,6 +2640,68 @@ const uint32_t *xc_get_feature_deep_deps(uint32_t
feature);
#endif
+int xc_xsplice_upload(xc_interface *xch,
+ char *name, unsigned char *payload, uint32_t size);
+
+int xc_xsplice_get(xc_interface *xch,
+ char *name,
+ xen_xsplice_status_t *status);
+
+/*
+ * The heart of this function is to get an array of xen_xsplice_status_t.
+ *
+ * However it is complex because it has to deal with the hypervisor
+ * returning some of the requested data or data being stale
+ * (another hypercall might alter the list).
+ *
+ * The parameters that the function expects to contain data from
+ * the hypervisor are: 'info', 'name', and 'len'. The 'done' and
+ * 'left' are also updated with the number of entries filled out
+ * and respectively the number of entries left to get from hypervisor.
+ *
+ * It is expected that the caller of this function will take the
+ * 'left' and use the value for 'start'. This way we have an
+ * cursor in the array. Note that the 'info','name', and 'len' will
+ * be updated at the subsequent calls.
+ *
+ * The 'max' is to be provided by the caller with the maximum
+ * number of entries that 'info', 'name', and 'len' arrays can
+ * be filled up with.
+ *
+ * Each entry in the 'name' array is expected to be of XEN_XSPLICE_NAME_SIZE
+ * length.
+ *
+ * Each entry in the 'info' array is expected to be of xen_xsplice_status_t
+ * structure size.
+ *
+ * Each entry in the 'len' array is expected to be of uint32_t size.
+ *
+ * The return value is zero if the hypercall completed successfully.
+ * Note that the return value is _not_ the amount of entries filled
+ * out - that is saved in 'done'.
+ *
+ * If there was an error performing the operation, the return value
+ * will contain an negative -EXX type value. The 'done' and 'left'
+ * will contain the number of entries that had been succesfully
+ * retrieved (if any).
+ */
+int xc_xsplice_list(xc_interface *xch, unsigned int max, unsigned int start,
+ xen_xsplice_status_t *info, char *name,
+ uint32_t *len, unsigned int *done,
+ unsigned int *left);
+
+/*
+ * The operations are asynchronous and the hypervisor may take a while
+ * to complete them. The `timeout` offers an option to expire the
+ * operation if it could not be completed within the specified time
+ * (in ms). Value of 0 means let hypervisor decide the best timeout.
+ */
+int xc_xsplice_apply(xc_interface *xch, char *name, uint32_t timeout);
+int xc_xsplice_revert(xc_interface *xch, char *name, uint32_t timeout);
+int xc_xsplice_unload(xc_interface *xch, char *name, uint32_t timeout);
+int xc_xsplice_check(xc_interface *xch, char *name, uint32_t timeout);
+int xc_xsplice_replace(xc_interface *xch, char *name, uint32_t timeout);
+
/* Compat shims */
#include "xenctrl_compat.h"
diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index 7d997d9..8cd398b 100644
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -696,6 +696,361 @@ int xc_hvm_inject_trap(
return rc;
}
+int xc_xsplice_upload(xc_interface *xch,
+ char *name,
+ unsigned char *payload,
+ uint32_t size)
+{
+ int rc;
+ DECLARE_SYSCTL;
+ DECLARE_HYPERCALL_BUFFER(char, local);
+ DECLARE_HYPERCALL_BOUNCE(name, 0 /* later */,
XC_HYPERCALL_BUFFER_BOUNCE_IN);
+ xen_xsplice_name_t def_name = { .pad = { 0, 0, 0 } };
+
+ if ( !name || !payload )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ def_name.size = strlen(name) + 1;
+ if ( def_name.size > XEN_XSPLICE_NAME_SIZE )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ HYPERCALL_BOUNCE_SET_SIZE(name, def_name.size);
+
+ if ( xc_hypercall_bounce_pre(xch, name) )
+ return -1;
+
+ local = xc_hypercall_buffer_alloc(xch, local, size);
+ if ( !local )
+ {
+ xc_hypercall_bounce_post(xch, name);
+ return -1;
+ }
+ memcpy(local, payload, size);
+
+ sysctl.cmd = XEN_SYSCTL_xsplice_op;
+ sysctl.u.xsplice.cmd = XEN_SYSCTL_XSPLICE_UPLOAD;
+ sysctl.u.xsplice.pad = 0;
+ sysctl.u.xsplice.u.upload.size = size;
+ set_xen_guest_handle(sysctl.u.xsplice.u.upload.payload, local);
+
+ sysctl.u.xsplice.u.upload.name = def_name;
+ set_xen_guest_handle(sysctl.u.xsplice.u.upload.name.name, name);
+
+ rc = do_sysctl(xch, &sysctl);
+
+ xc_hypercall_buffer_free(xch, local);
+ xc_hypercall_bounce_post(xch, name);
+
+ return rc;
+}
+
+int xc_xsplice_get(xc_interface *xch,
+ char *name,
+ xen_xsplice_status_t *status)
+{
+ int rc;
+ DECLARE_SYSCTL;
+ DECLARE_HYPERCALL_BOUNCE(name, 0 /*adjust later */,
XC_HYPERCALL_BUFFER_BOUNCE_IN);
+ xen_xsplice_name_t def_name = { .pad = { 0, 0, 0 } };
+
+ if ( !name )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ def_name.size = strlen(name) + 1;
+ if ( def_name.size > XEN_XSPLICE_NAME_SIZE )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ HYPERCALL_BOUNCE_SET_SIZE(name, def_name.size);
+
+ if ( xc_hypercall_bounce_pre(xch, name) )
+ return -1;
+
+ sysctl.cmd = XEN_SYSCTL_xsplice_op;
+ sysctl.u.xsplice.cmd = XEN_SYSCTL_XSPLICE_GET;
+ sysctl.u.xsplice.pad = 0;
+
+ sysctl.u.xsplice.u.get.status.state = 0;
+ sysctl.u.xsplice.u.get.status.rc = 0;
+
+ sysctl.u.xsplice.u.get.name = def_name;
+ set_xen_guest_handle(sysctl.u.xsplice.u.get.name.name, name);
+
+ rc = do_sysctl(xch, &sysctl);
+
+ xc_hypercall_bounce_post(xch, name);
+
+ memcpy(status, &sysctl.u.xsplice.u.get.status, sizeof(*status));
+
+ return rc;
+}
+
+/*
+ * The heart of this function is to get an array of xen_xsplice_status_t.
+ *
+ * However it is complex because it has to deal with the hypervisor
+ * returning some of the requested data or data being stale
+ * (another hypercall might alter the list).
+ *
+ * The parameters that the function expects to contain data from
+ * the hypervisor are: 'info', 'name', and 'len'. The 'done' and
+ * 'left' are also updated with the number of entries filled out
+ * and respectively the number of entries left to get from hypervisor.
+ *
+ * It is expected that the caller of this function will take the
+ * 'left' and use the value for 'start'. This way we have an
+ * cursor in the array. Note that the 'info','name', and 'len' will
+ * be updated at the subsequent calls.
+ *
+ * The 'max' is to be provided by the caller with the maximum
+ * number of entries that 'info', 'name', and 'len' arrays can
+ * be filled up with.
+ *
+ * Each entry in the 'name' array is expected to be of XEN_XSPLICE_NAME_SIZE
+ * length.
+ *
+ * Each entry in the 'info' array is expected to be of xen_xsplice_status_t
+ * structure size.
+ *
+ * Each entry in the 'len' array is expected to be of uint32_t size.
+ *
+ * The return value is zero if the hypercall completed successfully.
+ * Note that the return value is _not_ the amount of entries filled
+ * out - that is saved in 'done'.
+ *
+ * If there was an error performing the operation, the return value
+ * will contain an negative -EXX type value. The 'done' and 'left'
+ * will contain the number of entries that had been succesfully
+ * retrieved (if any).
+ */
+int xc_xsplice_list(xc_interface *xch, unsigned int max, unsigned int start,
+ xen_xsplice_status_t *info,
+ char *name, uint32_t *len,
+ unsigned int *done,
+ unsigned int *left)
+{
+ int rc;
+ DECLARE_SYSCTL;
+ /* The sizes are adjusted later - hence zero. */
+ DECLARE_HYPERCALL_BOUNCE(info, 0, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+ DECLARE_HYPERCALL_BOUNCE(name, 0, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+ DECLARE_HYPERCALL_BOUNCE(len, 0, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+ uint32_t max_batch_sz, nr;
+ uint32_t version = 0, retries = 0;
+ uint32_t adjust = 0;
+ ssize_t sz;
+
+ if ( !max || !info || !name || !len )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ sysctl.cmd = XEN_SYSCTL_xsplice_op;
+ sysctl.u.xsplice.cmd = XEN_SYSCTL_XSPLICE_LIST;
+ sysctl.u.xsplice.pad = 0;
+ sysctl.u.xsplice.u.list.version = 0;
+ sysctl.u.xsplice.u.list.idx = start;
+ sysctl.u.xsplice.u.list.pad = 0;
+
+ max_batch_sz = max;
+ /* Convience value. */
+ sz = sizeof(*name) * XEN_XSPLICE_NAME_SIZE;
+ *done = 0;
+ *left = 0;
+ do {
+ /*
+ * The first time we go in this loop our 'max' may be bigger
+ * than what the hypervisor is comfortable with - hence the first
+ * couple of loops may adjust the number of entries we will
+ * want filled (tracked by 'nr').
+ *
+ * N.B. This is a do { } while loop and the right hand side of
+ * the conditional when adjusting will evaluate to false (as
+ * *left is set to zero before the loop. Hence we need this
+ * adjust - even if we reset it at the start of the loop.
+ */
+ if ( adjust )
+ adjust = 0; /* Used when adjusting the 'max_batch_sz' or
'retries'. */
+
+ nr = min(max - *done, max_batch_sz);
+
+ sysctl.u.xsplice.u.list.nr = nr;
+ /* Fix the size (may vary between hypercalls). */
+ HYPERCALL_BOUNCE_SET_SIZE(info, nr * sizeof(*info));
+ HYPERCALL_BOUNCE_SET_SIZE(name, nr * nr);
+ HYPERCALL_BOUNCE_SET_SIZE(len, nr * sizeof(*len));
+ /* Move the pointer to proper offset into 'info'. */
+ (HYPERCALL_BUFFER(info))->ubuf = info + *done;
+ (HYPERCALL_BUFFER(name))->ubuf = name + (sz * *done);
+ (HYPERCALL_BUFFER(len))->ubuf = len + *done;
+ /* Allocate memory. */
+ rc = xc_hypercall_bounce_pre(xch, info);
+ if ( rc )
+ break;
+
+ rc = xc_hypercall_bounce_pre(xch, name);
+ if ( rc )
+ break;
+
+ rc = xc_hypercall_bounce_pre(xch, len);
+ if ( rc )
+ break;
+
+ set_xen_guest_handle(sysctl.u.xsplice.u.list.status, info);
+ set_xen_guest_handle(sysctl.u.xsplice.u.list.name, name);
+ set_xen_guest_handle(sysctl.u.xsplice.u.list.len, len);
+
+ rc = do_sysctl(xch, &sysctl);
+ /*
+ * From here on we MUST call xc_hypercall_bounce. If rc < 0 we
+ * end up doing it (outside the loop), so using a break is OK.
+ */
+ if ( rc < 0 && errno == E2BIG )
+ {
+ if ( max_batch_sz <= 1 )
+ break;
+ max_batch_sz >>= 1;
+ adjust = 1; /* For the loop conditional to let us loop again. */
+ /* No memory leaks! */
+ xc_hypercall_bounce_post(xch, info);
+ xc_hypercall_bounce_post(xch, name);
+ xc_hypercall_bounce_post(xch, len);
+ continue;
+ }
+ else if ( rc < 0 ) /* For all other errors we bail out. */
+ break;
+
+ if ( !version )
+ version = sysctl.u.xsplice.u.list.version;
+
+ if ( sysctl.u.xsplice.u.list.version != version )
+ {
+ /* We could make this configurable as parameter? */
+ if ( retries++ > 3 )
+ {
+ rc = -1;
+ errno = EBUSY;
+ break;
+ }
+ *done = 0; /* Retry from scratch. */
+ version = sysctl.u.xsplice.u.list.version;
+ adjust = 1; /* And make sure we continue in the loop. */
+ /* No memory leaks. */
+ xc_hypercall_bounce_post(xch, info);
+ xc_hypercall_bounce_post(xch, name);
+ xc_hypercall_bounce_post(xch, len);
+ continue;
+ }
+
+ /* We should never hit this, but just in case. */
+ if ( rc > nr )
+ {
+ errno = EOVERFLOW; /* Overflow! */
+ rc = -1;
+ break;
+ }
+ *left = sysctl.u.xsplice.u.list.nr; /* Total remaining count. */
+ /* Copy only up 'rc' of data' - we could add 'min(rc,nr) if desired. */
+ HYPERCALL_BOUNCE_SET_SIZE(info, (rc * sizeof(*info)));
+ HYPERCALL_BOUNCE_SET_SIZE(name, (rc * sz));
+ HYPERCALL_BOUNCE_SET_SIZE(len, (rc * sizeof(*len)));
+ /* Bounce the data and free the bounce buffer. */
+ xc_hypercall_bounce_post(xch, info);
+ xc_hypercall_bounce_post(xch, name);
+ xc_hypercall_bounce_post(xch, len);
+ /* And update how many elements of info we have copied into. */
+ *done += rc;
+ /* Update idx. */
+ sysctl.u.xsplice.u.list.idx = *done;
+ } while ( adjust || (*done < max && *left != 0) );
+
+ if ( rc < 0 )
+ {
+ xc_hypercall_bounce_post(xch, len);
+ xc_hypercall_bounce_post(xch, name);
+ xc_hypercall_bounce_post(xch, info);
+ }
+
+ return rc > 0 ? 0 : rc;
+}
+
+static int _xc_xsplice_action(xc_interface *xch,
+ char *name,
+ unsigned int action,
+ uint32_t timeout)
+{
+ int rc;
+ DECLARE_SYSCTL;
+ /* The size is figured out when we strlen(name) */
+ DECLARE_HYPERCALL_BOUNCE(name, 0, XC_HYPERCALL_BUFFER_BOUNCE_IN);
+ xen_xsplice_name_t def_name = { .pad = { 0, 0, 0 } };
+
+ def_name.size = strlen(name) + 1;
+
+ if ( def_name.size > XEN_XSPLICE_NAME_SIZE )
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ HYPERCALL_BOUNCE_SET_SIZE(name, def_name.size);
+
+ if ( xc_hypercall_bounce_pre(xch, name) )
+ return -1;
+
+ sysctl.cmd = XEN_SYSCTL_xsplice_op;
+ sysctl.u.xsplice.cmd = XEN_SYSCTL_XSPLICE_ACTION;
+ sysctl.u.xsplice.pad = 0;
+ sysctl.u.xsplice.u.action.cmd = action;
+ sysctl.u.xsplice.u.action.timeout = timeout;
+
+ sysctl.u.xsplice.u.action.name = def_name;
+ set_xen_guest_handle(sysctl.u.xsplice.u.action.name.name, name);
+
+ rc = do_sysctl(xch, &sysctl);
+
+ xc_hypercall_bounce_post(xch, name);
+
+ return rc;
+}
+
+int xc_xsplice_apply(xc_interface *xch, char *name, uint32_t timeout)
+{
+ return _xc_xsplice_action(xch, name, XSPLICE_ACTION_APPLY, timeout);
+}
+
+int xc_xsplice_revert(xc_interface *xch, char *name, uint32_t timeout)
+{
+ return _xc_xsplice_action(xch, name, XSPLICE_ACTION_REVERT, timeout);
+}
+
+int xc_xsplice_unload(xc_interface *xch, char *name, uint32_t timeout)
+{
+ return _xc_xsplice_action(xch, name, XSPLICE_ACTION_UNLOAD, timeout);
+}
+
+int xc_xsplice_check(xc_interface *xch, char *name, uint32_t timeout)
+{
+ return _xc_xsplice_action(xch, name, XSPLICE_ACTION_CHECK, timeout);
+}
+
+int xc_xsplice_replace(xc_interface *xch, char *name, uint32_t timeout)
+{
+ return _xc_xsplice_action(xch, name, XSPLICE_ACTION_REPLACE, timeout);
+}
+
/*
* Local variables:
* mode: C
--
2.5.0
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