diff mbox series

[v4,18/29] vhost+postcopy: Resolve client address

Message ID 20180308195811.24894-19-dgilbert@redhat.com
State New
Headers show
Series postcopy+vhost-user/shared ram | expand

Commit Message

Dr. David Alan Gilbert March 8, 2018, 7:58 p.m. UTC 
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Resolve fault addresses read off the clients UFD into RAMBlock
and offset, and call back to the postcopy code to ask for the page.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
 hw/virtio/trace-events |  3 +++
 hw/virtio/vhost-user.c | 31 ++++++++++++++++++++++++++++++-
 2 files changed, 33 insertions(+), 1 deletion(-)

Comments

Marc-André Lureau March 12, 2018, 3:40 p.m. UTC | #1 
Hi

On Thu, Mar 8, 2018 at 8:58 PM, Dr. David Alan Gilbert (git)
<dgilbert@redhat.com> wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
>
> Resolve fault addresses read off the clients UFD into RAMBlock
> and offset, and call back to the postcopy code to ask for the page.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Reviewed-by: Peter Xu <peterx@redhat.com>

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>


> ---
>  hw/virtio/trace-events |  3 +++
>  hw/virtio/vhost-user.c | 31 ++++++++++++++++++++++++++++++-
>  2 files changed, 33 insertions(+), 1 deletion(-)
>
> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> index d7e9e1084b..3afd12cfea 100644
> --- a/hw/virtio/trace-events
> +++ b/hw/virtio/trace-events
> @@ -7,6 +7,9 @@ vhost_region_add_section_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx
>  vhost_section(const char *name, int r) "%s:%d"
>
>  # hw/virtio/vhost-user.c
> +vhost_user_postcopy_fault_handler(const char *name, uint64_t fault_address, int nregions) "%s: @0x%"PRIx64" nregions:%d"
> +vhost_user_postcopy_fault_handler_loop(int i, uint64_t client_base, uint64_t size) "%d: client 0x%"PRIx64" +0x%"PRIx64
> +vhost_user_postcopy_fault_handler_found(int i, uint64_t region_offset, uint64_t rb_offset) "%d: region_offset: 0x%"PRIx64" rb_offset:0x%"PRIx64
>  vhost_user_postcopy_listen(void) ""
>  vhost_user_set_mem_table_postcopy(uint64_t client_addr, uint64_t qhva, int reply_i, int region_i) "client:0x%"PRIx64" for hva: 0x%"PRIx64" reply %d region %d"
>  vhost_user_set_mem_table_withfd(int index, const char *name, uint64_t memory_size, uint64_t guest_phys_addr, uint64_t userspace_addr, uint64_t offset) "%d:%s: size:0x%"PRIx64" GPA:0x%"PRIx64" QVA/userspace:0x%"PRIx64" RB offset:0x%"PRIx64
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index fd65616961..e19b9ef9cf 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -26,6 +26,7 @@
>  #include <sys/socket.h>
>  #include <sys/un.h>
>  #include <linux/vhost.h>
> +#include <linux/userfaultfd.h>
>
>  #define VHOST_MEMORY_MAX_NREGIONS    8
>  #define VHOST_USER_F_PROTOCOL_FEATURES 30
> @@ -974,7 +975,35 @@ out:
>  static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
>                                               void *ufd)
>  {
> -    return 0;
> +    struct vhost_dev *dev = pcfd->data;
> +    struct vhost_user *u = dev->opaque;
> +    struct uffd_msg *msg = ufd;
> +    uint64_t faultaddr = msg->arg.pagefault.address;
> +    RAMBlock *rb = NULL;
> +    uint64_t rb_offset;
> +    int i;
> +
> +    trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
> +                                            dev->mem->nregions);
> +    for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
> +        trace_vhost_user_postcopy_fault_handler_loop(i,
> +                u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
> +        if (faultaddr >= u->postcopy_client_bases[i]) {
> +            /* Ofset of the fault address in the vhost region */
> +            uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
> +            if (region_offset < dev->mem->regions[i].memory_size) {
> +                rb_offset = region_offset + u->region_rb_offset[i];

It may be worth to add an assert (i < u->region_rb_len) ?

> +                trace_vhost_user_postcopy_fault_handler_found(i,
> +                        region_offset, rb_offset);
> +                rb = u->region_rb[i];
> +                return postcopy_request_shared_page(pcfd, rb, faultaddr,
> +                                                    rb_offset);
> +            }
> +        }
> +    }
> +    error_report("%s: Failed to find region for fault %" PRIx64,
> +                 __func__, faultaddr);
> +    return -1;
>  }
>
>  /*
> --
> 2.14.3
>
>
Dr. David Alan Gilbert March 12, 2018, 5:03 p.m. UTC | #2 
* Marc-André Lureau (marcandre.lureau@gmail.com) wrote:
> Hi
> 
> On Thu, Mar 8, 2018 at 8:58 PM, Dr. David Alan Gilbert (git)
> <dgilbert@redhat.com> wrote:
> > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> >
> > Resolve fault addresses read off the clients UFD into RAMBlock
> > and offset, and call back to the postcopy code to ask for the page.
> >
> > Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> > Reviewed-by: Peter Xu <peterx@redhat.com>
> 
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

Thanks,

> 
> > ---
> >  hw/virtio/trace-events |  3 +++
> >  hw/virtio/vhost-user.c | 31 ++++++++++++++++++++++++++++++-
> >  2 files changed, 33 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> > index d7e9e1084b..3afd12cfea 100644
> > --- a/hw/virtio/trace-events
> > +++ b/hw/virtio/trace-events
> > @@ -7,6 +7,9 @@ vhost_region_add_section_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx
> >  vhost_section(const char *name, int r) "%s:%d"
> >
> >  # hw/virtio/vhost-user.c
> > +vhost_user_postcopy_fault_handler(const char *name, uint64_t fault_address, int nregions) "%s: @0x%"PRIx64" nregions:%d"
> > +vhost_user_postcopy_fault_handler_loop(int i, uint64_t client_base, uint64_t size) "%d: client 0x%"PRIx64" +0x%"PRIx64
> > +vhost_user_postcopy_fault_handler_found(int i, uint64_t region_offset, uint64_t rb_offset) "%d: region_offset: 0x%"PRIx64" rb_offset:0x%"PRIx64
> >  vhost_user_postcopy_listen(void) ""
> >  vhost_user_set_mem_table_postcopy(uint64_t client_addr, uint64_t qhva, int reply_i, int region_i) "client:0x%"PRIx64" for hva: 0x%"PRIx64" reply %d region %d"
> >  vhost_user_set_mem_table_withfd(int index, const char *name, uint64_t memory_size, uint64_t guest_phys_addr, uint64_t userspace_addr, uint64_t offset) "%d:%s: size:0x%"PRIx64" GPA:0x%"PRIx64" QVA/userspace:0x%"PRIx64" RB offset:0x%"PRIx64
> > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> > index fd65616961..e19b9ef9cf 100644
> > --- a/hw/virtio/vhost-user.c
> > +++ b/hw/virtio/vhost-user.c
> > @@ -26,6 +26,7 @@
> >  #include <sys/socket.h>
> >  #include <sys/un.h>
> >  #include <linux/vhost.h>
> > +#include <linux/userfaultfd.h>
> >
> >  #define VHOST_MEMORY_MAX_NREGIONS    8
> >  #define VHOST_USER_F_PROTOCOL_FEATURES 30
> > @@ -974,7 +975,35 @@ out:
> >  static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
> >                                               void *ufd)
> >  {
> > -    return 0;
> > +    struct vhost_dev *dev = pcfd->data;
> > +    struct vhost_user *u = dev->opaque;
> > +    struct uffd_msg *msg = ufd;
> > +    uint64_t faultaddr = msg->arg.pagefault.address;
> > +    RAMBlock *rb = NULL;
> > +    uint64_t rb_offset;
> > +    int i;
> > +
> > +    trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
> > +                                            dev->mem->nregions);
> > +    for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
> > +        trace_vhost_user_postcopy_fault_handler_loop(i,
> > +                u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
> > +        if (faultaddr >= u->postcopy_client_bases[i]) {
> > +            /* Ofset of the fault address in the vhost region */
> > +            uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
> > +            if (region_offset < dev->mem->regions[i].memory_size) {
> > +                rb_offset = region_offset + u->region_rb_offset[i];
> 
> It may be worth to add an assert (i < u->region_rb_len) ?

The loop limit guarantees that anyway with the 2nd term of the
MIN.

Dave

> 
> > +                trace_vhost_user_postcopy_fault_handler_found(i,
> > +                        region_offset, rb_offset);
> > +                rb = u->region_rb[i];
> > +                return postcopy_request_shared_page(pcfd, rb, faultaddr,
> > +                                                    rb_offset);
> > +            }
> > +        }
> > +    }
> > +    error_report("%s: Failed to find region for fault %" PRIx64,
> > +                 __func__, faultaddr);
> > +    return -1;
> >  }
> >
> >  /*
> > --
> > 2.14.3
> >
> >
> 
> 
> 
> -- 
> Marc-André Lureau
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff mbox series

Patch

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index d7e9e1084b..3afd12cfea 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -7,6 +7,9 @@  vhost_region_add_section_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx
 vhost_section(const char *name, int r) "%s:%d"
 
 # hw/virtio/vhost-user.c
+vhost_user_postcopy_fault_handler(const char *name, uint64_t fault_address, int nregions) "%s: @0x%"PRIx64" nregions:%d"
+vhost_user_postcopy_fault_handler_loop(int i, uint64_t client_base, uint64_t size) "%d: client 0x%"PRIx64" +0x%"PRIx64
+vhost_user_postcopy_fault_handler_found(int i, uint64_t region_offset, uint64_t rb_offset) "%d: region_offset: 0x%"PRIx64" rb_offset:0x%"PRIx64
 vhost_user_postcopy_listen(void) ""
 vhost_user_set_mem_table_postcopy(uint64_t client_addr, uint64_t qhva, int reply_i, int region_i) "client:0x%"PRIx64" for hva: 0x%"PRIx64" reply %d region %d"
 vhost_user_set_mem_table_withfd(int index, const char *name, uint64_t memory_size, uint64_t guest_phys_addr, uint64_t userspace_addr, uint64_t offset) "%d:%s: size:0x%"PRIx64" GPA:0x%"PRIx64" QVA/userspace:0x%"PRIx64" RB offset:0x%"PRIx64
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index fd65616961..e19b9ef9cf 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -26,6 +26,7 @@ 
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <linux/vhost.h>
+#include <linux/userfaultfd.h>
 
 #define VHOST_MEMORY_MAX_NREGIONS    8
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
@@ -974,7 +975,35 @@  out:
 static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
                                              void *ufd)
 {
-    return 0;
+    struct vhost_dev *dev = pcfd->data;
+    struct vhost_user *u = dev->opaque;
+    struct uffd_msg *msg = ufd;
+    uint64_t faultaddr = msg->arg.pagefault.address;
+    RAMBlock *rb = NULL;
+    uint64_t rb_offset;
+    int i;
+
+    trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
+                                            dev->mem->nregions);
+    for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
+        trace_vhost_user_postcopy_fault_handler_loop(i,
+                u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
+        if (faultaddr >= u->postcopy_client_bases[i]) {
+            /* Ofset of the fault address in the vhost region */
+            uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
+            if (region_offset < dev->mem->regions[i].memory_size) {
+                rb_offset = region_offset + u->region_rb_offset[i];
+                trace_vhost_user_postcopy_fault_handler_found(i,
+                        region_offset, rb_offset);
+                rb = u->region_rb[i];
+                return postcopy_request_shared_page(pcfd, rb, faultaddr,
+                                                    rb_offset);
+            }
+        }
+    }
+    error_report("%s: Failed to find region for fault %" PRIx64,
+                 __func__, faultaddr);
+    return -1;
 }
 
 /*