This patch allows grant table frames to be mapped using the XENMEM_acquire_resource memory op.
Signed-off-by: Paul Durrant <paul.durr...@citrix.com> --- Cc: Andrew Cooper <andrew.coop...@citrix.com> Cc: George Dunlap <george.dun...@eu.citrix.com> Cc: Ian Jackson <ian.jack...@eu.citrix.com> Cc: Jan Beulich <jbeul...@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> Cc: Stefano Stabellini <sstabell...@kernel.org> Cc: Tim Deegan <t...@xen.org> Cc: Wei Liu <wei.l...@citrix.com> v10: - Addressed comments from Jan. v8: - The functionality was originally incorporated into the earlier patch "x86/mm: add HYPERVISOR_memory_op to acquire guest resources". --- xen/common/grant_table.c | 63 ++++++++++++++++++++++++++++++++++++++----- xen/common/memory.c | 44 +++++++++++++++++++++++++++++- xen/include/public/memory.h | 6 +++++ xen/include/xen/grant_table.h | 4 +++ 4 files changed, 110 insertions(+), 7 deletions(-) diff --git a/xen/common/grant_table.c b/xen/common/grant_table.c index 6d20b17739..e42c1b6bf3 100644 --- a/xen/common/grant_table.c +++ b/xen/common/grant_table.c @@ -1608,7 +1608,8 @@ fault: } static int -gnttab_populate_status_frames(struct domain *d, struct grant_table *gt, +gnttab_populate_status_frames(struct domain *d, + struct grant_table *gt, unsigned int req_nr_frames) { unsigned i; @@ -3756,13 +3757,12 @@ int mem_sharing_gref_to_gfn(struct grant_table *gt, grant_ref_t ref, } #endif -int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn, - mfn_t *mfn) +/* Caller must hold write lock as version may change and table may grow */ +static int gnttab_get_frame(struct domain *d, unsigned long idx, + mfn_t *mfn) { - int rc = 0; struct grant_table *gt = d->grant_table; - - grant_write_lock(gt); + int rc = 0; if ( gt->gt_version == 0 ) gt->gt_version = 1; @@ -3787,6 +3787,19 @@ int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn, rc = -EINVAL; } + return rc; +} + +int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn, + mfn_t *mfn) +{ + struct grant_table *gt = d->grant_table; + int rc; + + grant_write_lock(gt); + + rc = gnttab_get_frame(d, idx, mfn); + if ( !rc ) gnttab_set_frame_gfn(gt, idx, gfn); @@ -3795,6 +3808,44 @@ int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn, return rc; } +int gnttab_get_grant_frame(struct domain *d, unsigned long idx, + mfn_t *mfn) +{ + struct grant_table *gt = d->grant_table; + int rc; + + /* write lock required as version may change and/or table may grow */ + grant_write_lock(gt); + + rc = (gt->gt_version == 2 && + idx > XENMAPIDX_grant_table_status) ? + -EINVAL : + gnttab_get_frame(d, idx, mfn); + + grant_write_unlock(gt); + + return rc; +} + +int gnttab_get_status_frame(struct domain *d, unsigned long idx, + mfn_t *mfn) +{ + struct grant_table *gt = d->grant_table; + int rc; + + /* write lock required as version may change and/or table may grow */ + grant_write_lock(gt); + + rc = (gt->gt_version != 2 || + idx > XENMAPIDX_grant_table_status) ? + -EINVAL : + gnttab_get_frame(d, idx & XENMAPIDX_grant_table_status, mfn); + + grant_write_unlock(gt); + + return rc; +} + static void gnttab_usage_print(struct domain *rd) { int first = 1; diff --git a/xen/common/memory.c b/xen/common/memory.c index 6f01cc9663..42d5440979 100644 --- a/xen/common/memory.c +++ b/xen/common/memory.c @@ -23,6 +23,7 @@ #include <xen/numa.h> #include <xen/mem_access.h> #include <xen/trace.h> +#include <xen/grant_table.h> #include <asm/current.h> #include <asm/hardirq.h> #include <asm/p2m.h> @@ -965,10 +966,46 @@ static long xatp_permission_check(struct domain *d, unsigned int space) return xsm_add_to_physmap(XSM_TARGET, current->domain, d); } +static int acquire_grant_table(struct domain *d, unsigned int id, + unsigned long frame, + unsigned int nr_frames, + unsigned long mfn_list[]) +{ + unsigned int i = nr_frames; + + while ( i-- != 0 ) + { + mfn_t mfn = INVALID_MFN; + int rc; + + switch ( id ) + { + case XENMEM_resource_grant_table_id_grant: + rc = gnttab_get_grant_frame(d, frame + i, &mfn); + break; + + case XENMEM_resource_grant_table_id_status: + rc = gnttab_get_status_frame(d, frame + i, &mfn); + break; + + default: + rc = -EINVAL; + break; + } + + if ( rc ) + return rc; + + mfn_list[i] = mfn_x(mfn); + } + + return 0; +} + static int acquire_resource(const xen_mem_acquire_resource_t *xmar) { struct domain *d, *currd = current->domain; - unsigned long mfn_list[2]; + unsigned long mfn_list[32]; int rc; if ( xmar->nr_frames == 0 || xmar->pad != 0 ) @@ -992,6 +1029,11 @@ static int acquire_resource(const xen_mem_acquire_resource_t *xmar) xmar->nr_frames, mfn_list); break; + case XENMEM_resource_grant_table: + rc = acquire_grant_table(d, xmar->id, xmar->frame, + xmar->nr_frames, mfn_list); + break; + default: rc = -EOPNOTSUPP; break; diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h index 1322527490..2c7832c411 100644 --- a/xen/include/public/memory.h +++ b/xen/include/public/memory.h @@ -611,14 +611,20 @@ struct xen_mem_acquire_resource { uint16_t type; #define XENMEM_resource_ioreq_server 0 +#define XENMEM_resource_grant_table 1 /* * IN - a type-specific resource identifier, which must be zero * unless stated otherwise. * * type == XENMEM_resource_ioreq_server -> id == ioreq server id + * type == XENMEM_resource_grant_table -> id defined below */ uint32_t id; + +#define XENMEM_resource_grant_table_id_grant 0 +#define XENMEM_resource_grant_table_id_status 1 + /* IN - number of (4K) frames of the resource to be mapped */ uint32_t nr_frames; uint32_t pad; diff --git a/xen/include/xen/grant_table.h b/xen/include/xen/grant_table.h index b3a95fda58..e9125e43e7 100644 --- a/xen/include/xen/grant_table.h +++ b/xen/include/xen/grant_table.h @@ -55,6 +55,10 @@ int mem_sharing_gref_to_gfn(struct grant_table *gt, grant_ref_t ref, int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn, mfn_t *mfn); +int gnttab_get_grant_frame(struct domain *d, unsigned long idx, + mfn_t *mfn); +int gnttab_get_status_frame(struct domain *d, unsigned long idx, + mfn_t *mfn); unsigned int gnttab_dom0_frames(void); -- 2.11.0 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel