Module Name: src
Committed By: jdolecek
Date: Sun Apr 19 18:47:40 UTC 2020
Modified Files:
src/sys/arch/xen/include: xen_shm.h
src/sys/arch/xen/x86: xen_shm_machdep.c
src/sys/arch/xen/xen: hypervisor.c xbdback_xenbus.c
Log Message:
change interface for xen_shm_map() so that caller always supplies the VA,
it now fails only if the Xen hypercall fails, in which case the failure
is final
change xbdback to pre-allocate KVA on xbdback attach (and free on detach),
so it has always KVA to map the request pages
remove no longer needed KVA allocation failure handling
To generate a diff of this commit:
cvs rdiff -u -r1.10 -r1.11 src/sys/arch/xen/include/xen_shm.h
cvs rdiff -u -r1.14 -r1.15 src/sys/arch/xen/x86/xen_shm_machdep.c
cvs rdiff -u -r1.74 -r1.75 src/sys/arch/xen/xen/hypervisor.c
cvs rdiff -u -r1.78 -r1.79 src/sys/arch/xen/xen/xbdback_xenbus.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/xen/include/xen_shm.h
diff -u src/sys/arch/xen/include/xen_shm.h:1.10 src/sys/arch/xen/include/xen_shm.h:1.11
--- src/sys/arch/xen/include/xen_shm.h:1.10 Tue Jan 8 19:59:24 2019
+++ src/sys/arch/xen/include/xen_shm.h Sun Apr 19 18:47:40 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: xen_shm.h,v 1.10 2019/01/08 19:59:24 jdolecek Exp $ */
+/* $NetBSD: xen_shm.h,v 1.11 2020/04/19 18:47:40 jdolecek Exp $ */
/*
* Copyright (c) 2005 Manuel Bouyer.
@@ -27,7 +27,7 @@
#include "opt_xen.h"
-#define XENSHM_MAX_PAGES_PER_REQUEST (MAXPHYS >> PAGE_SHIFT)
+#define XENSHM_MAX_PAGES_PER_REQUEST ((MAXPHYS + PAGE_SIZE) >> PAGE_SHIFT)
/*
* Helper routines for the backend drivers. This implement the necessary
@@ -35,10 +35,8 @@
* space, do I/O to it, and unmap it.
*/
-int xen_shm_map(int, int, grant_ref_t *, vaddr_t *, grant_handle_t *, int);
+int xen_shm_map(int, int, grant_ref_t *, vaddr_t, grant_handle_t *, int);
void xen_shm_unmap(vaddr_t, int, grant_handle_t *);
-int xen_shm_callback(int (*)(void *), void *);
/* flags for xen_shm_map() */
-#define XSHM_CALLBACK 0x01 /* called from a callback */
#define XSHM_RO 0x02 /* map the guest's memory read-only */
Index: src/sys/arch/xen/x86/xen_shm_machdep.c
diff -u src/sys/arch/xen/x86/xen_shm_machdep.c:1.14 src/sys/arch/xen/x86/xen_shm_machdep.c:1.15
--- src/sys/arch/xen/x86/xen_shm_machdep.c:1.14 Mon Apr 13 00:27:16 2020
+++ src/sys/arch/xen/x86/xen_shm_machdep.c Sun Apr 19 18:47:40 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: xen_shm_machdep.c,v 1.14 2020/04/13 00:27:16 chs Exp $ */
+/* $NetBSD: xen_shm_machdep.c,v 1.15 2020/04/19 18:47:40 jdolecek Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -25,7 +25,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xen_shm_machdep.c,v 1.14 2020/04/13 00:27:16 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xen_shm_machdep.c,v 1.15 2020/04/19 18:47:40 jdolecek Exp $");
#include <sys/types.h>
#include <sys/param.h>
@@ -55,71 +55,12 @@ __KERNEL_RCSID(0, "$NetBSD: xen_shm_mach
* available.
*/
-/* Grab enough VM space to map an entire vbd ring. */
-/* Xen3 linux guests seems to eat more pages, gives enough for 10 vbd rings */
-#define BLKIF_RING_SIZE __RING_SIZE((blkif_sring_t *)0, PAGE_SIZE)
-#define XENSHM_NPAGES (BLKIF_RING_SIZE * (BLKIF_MAX_SEGMENTS_PER_REQUEST + 1) * 10)
-
-/* vm space management */
-static vmem_t *xen_shm_arena __read_mostly;
-
-/* callbacks are registered in a FIFO list. */
-static SIMPLEQ_HEAD(xen_shm_callback_head, xen_shm_callback_entry)
- xen_shm_callbacks;
-
-struct xen_shm_callback_entry {
- SIMPLEQ_ENTRY(xen_shm_callback_entry) xshmc_entries;
- int (*xshmc_callback)(void *); /* our callback */
- void *xshmc_arg; /* cookie passed to the callback */
-};
-
-/* a pool of struct xen_shm_callback_entry */
-static struct pool xen_shm_callback_pool;
-
-#ifdef DEBUG
-/* for ratecheck(9) */
-static struct timeval xen_shm_errintvl = { 60, 0 }; /* a minute, each */
-#endif
-
-void
-xen_shm_init(void)
-{
- vaddr_t xen_shm_base_address;
- vaddr_t xen_shm_end_address;
- u_long xen_shm_base_address_pg;
- vsize_t xen_shm_size;
-
- SIMPLEQ_INIT(&xen_shm_callbacks);
- pool_init(&xen_shm_callback_pool, sizeof(struct xen_shm_callback_entry),
- 0, 0, 0, "xshmc", NULL, IPL_VM);
- /* ensure we'll always get items */
- pool_prime(&xen_shm_callback_pool, 1);
-
- xen_shm_size = (XENSHM_NPAGES * PAGE_SIZE);
-
- xen_shm_base_address = uvm_km_alloc(kernel_map, xen_shm_size, 0,
- UVM_KMF_VAONLY);
- xen_shm_end_address = xen_shm_base_address + xen_shm_size;
- xen_shm_base_address_pg = xen_shm_base_address >> PAGE_SHIFT;
- if (xen_shm_base_address == 0) {
- panic("xen_shm_init no VM space");
- }
- xen_shm_arena = vmem_create("xen_shm", xen_shm_base_address_pg,
- (xen_shm_end_address >> PAGE_SHIFT) - 1 - xen_shm_base_address_pg,
- 1, NULL, NULL, NULL, 1, VM_NOSLEEP, IPL_VM);
- if (xen_shm_arena == NULL) {
- panic("xen_shm_init no arena");
- }
-}
-
int
-xen_shm_map(int nentries, int domid, grant_ref_t *grefp, vaddr_t *vap,
+xen_shm_map(int nentries, int domid, grant_ref_t *grefp, vaddr_t va,
grant_handle_t *handlep, int flags)
{
gnttab_map_grant_ref_t op[XENSHM_MAX_PAGES_PER_REQUEST];
- vmem_addr_t new_va_pg;
- vaddr_t new_va;
- int ret, i, s;
+ int ret, i;
#ifdef DIAGNOSTIC
if (nentries > XENSHM_MAX_PAGES_PER_REQUEST) {
@@ -127,41 +68,8 @@ xen_shm_map(int nentries, int domid, gra
}
#endif
- /* XXXSMP */
- s = splvm(); /* splvm is the lowest level blocking disk and net IRQ */
-
- /*
- * If a driver is waiting for resources, don't try to allocate
- * yet. This is to avoid a flood of small requests stalling large
- * ones.
- */
- if (__predict_false(SIMPLEQ_FIRST(&xen_shm_callbacks) != NULL) &&
- (flags & XSHM_CALLBACK) == 0) {
- splx(s);
-#ifdef DEBUG
- static struct timeval lasttime;
- if (ratecheck(&lasttime, &xen_shm_errintvl))
- printf("xen_shm_map: ENOMEM1\n");
-#endif
- return ENOMEM;
- }
-
- /* Allocate the needed virtual space. */
- if (vmem_alloc(xen_shm_arena, nentries,
- VM_INSTANTFIT | VM_NOSLEEP, &new_va_pg) != 0) {
- splx(s);
-#ifdef DEBUG
- static struct timeval lasttime;
- if (ratecheck(&lasttime, &xen_shm_errintvl))
- printf("xen_shm_map: ENOMEM\n");
-#endif
- return ENOMEM;
- }
- splx(s);
-
- new_va = new_va_pg << PAGE_SHIFT;
for (i = 0; i < nentries; i++) {
- op[i].host_addr = new_va + i * PAGE_SIZE;
+ op[i].host_addr = va + i * PAGE_SIZE;
op[i].dom = domid;
op[i].ref = grefp[i];
op[i].flags = GNTMAP_host_map |
@@ -170,16 +78,19 @@ xen_shm_map(int nentries, int domid, gra
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, op, nentries);
if (__predict_false(ret)) {
- panic("xen_shm_map: HYPERVISOR_grant_table_op failed");
+ printf("%s: HYPERVISOR_grant_table_op failed\n", __func__);
+ return EINVAL;
}
for (i = 0; i < nentries; i++) {
+#ifdef DIAGNOSTIC
if (__predict_false(op[i].status))
- return op[i].status;
+ panic("%s: op[%d] status %d", __func__, i,
+ op[i].status);
+#endif
handlep[i] = op[i].handle;
}
- *vap = new_va;
return 0;
}
@@ -187,8 +98,7 @@ void
xen_shm_unmap(vaddr_t va, int nentries, grant_handle_t *handlep)
{
gnttab_unmap_grant_ref_t op[XENSHM_MAX_PAGES_PER_REQUEST];
- struct xen_shm_callback_entry *xshmc;
- int ret, i, s;
+ int ret, i;
#ifdef DIAGNOSTIC
if (nentries > XENSHM_MAX_PAGES_PER_REQUEST) {
@@ -207,48 +117,4 @@ xen_shm_unmap(vaddr_t va, int nentries,
if (__predict_false(ret)) {
panic("xen_shm_unmap: unmap failed");
}
-
- va = va >> PAGE_SHIFT;
-
- /* XXXSMP */
- s = splvm(); /* splvm is the lowest level blocking disk and net IRQ */
-
- vmem_free(xen_shm_arena, va, nentries);
- while (__predict_false((xshmc = SIMPLEQ_FIRST(&xen_shm_callbacks))
- != NULL)) {
- SIMPLEQ_REMOVE_HEAD(&xen_shm_callbacks, xshmc_entries);
- splx(s);
- if (xshmc->xshmc_callback(xshmc->xshmc_arg) == 0) {
- /* callback succeeded */
- s = splvm(); /* XXXSMP */
- pool_put(&xen_shm_callback_pool, xshmc);
- } else {
- /* callback failed, probably out of resources */
- s = splvm(); /* XXXSMP */
- SIMPLEQ_INSERT_TAIL(&xen_shm_callbacks, xshmc,
- xshmc_entries);
- break;
- }
- }
-
- splx(s);
-}
-
-int
-xen_shm_callback(int (*callback)(void *), void *arg)
-{
- struct xen_shm_callback_entry *xshmc;
- int s;
-
- s = splvm(); /* XXXSMP */
- xshmc = pool_get(&xen_shm_callback_pool, PR_NOWAIT);
- if (xshmc == NULL) {
- splx(s);
- return ENOMEM;
- }
- xshmc->xshmc_arg = arg;
- xshmc->xshmc_callback = callback;
- SIMPLEQ_INSERT_TAIL(&xen_shm_callbacks, xshmc, xshmc_entries);
- splx(s);
- return 0;
}
Index: src/sys/arch/xen/xen/hypervisor.c
diff -u src/sys/arch/xen/xen/hypervisor.c:1.74 src/sys/arch/xen/xen/hypervisor.c:1.75
--- src/sys/arch/xen/xen/hypervisor.c:1.74 Fri Apr 10 14:54:33 2020
+++ src/sys/arch/xen/xen/hypervisor.c Sun Apr 19 18:47:40 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: hypervisor.c,v 1.74 2020/04/10 14:54:33 jdolecek Exp $ */
+/* $NetBSD: hypervisor.c,v 1.75 2020/04/19 18:47:40 jdolecek Exp $ */
/*
* Copyright (c) 2005 Manuel Bouyer.
@@ -53,7 +53,7 @@
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: hypervisor.c,v 1.74 2020/04/10 14:54:33 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: hypervisor.c,v 1.75 2020/04/19 18:47:40 jdolecek Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -415,7 +415,7 @@ hypervisor_match(device_t parent, cfdata
bi.common.len = sizeof(struct btinfo_rootdevice);
/* From i386/multiboot.c */
- /* $NetBSD: hypervisor.c,v 1.74 2020/04/10 14:54:33 jdolecek Exp $ */
+ /* $NetBSD: hypervisor.c,v 1.75 2020/04/19 18:47:40 jdolecek Exp $ */
int i, len;
vaddr_t data;
extern struct bootinfo bootinfo;
@@ -620,7 +620,6 @@ hypervisor_attach(device_t parent, devic
if (xendomain_is_privileged()) {
xenprivcmd_init();
- xen_shm_init();
}
#endif /* DOM0OPS */
Index: src/sys/arch/xen/xen/xbdback_xenbus.c
diff -u src/sys/arch/xen/xen/xbdback_xenbus.c:1.78 src/sys/arch/xen/xen/xbdback_xenbus.c:1.79
--- src/sys/arch/xen/xen/xbdback_xenbus.c:1.78 Mon Apr 13 00:27:17 2020
+++ src/sys/arch/xen/xen/xbdback_xenbus.c Sun Apr 19 18:47:40 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: xbdback_xenbus.c,v 1.78 2020/04/13 00:27:17 chs Exp $ */
+/* $NetBSD: xbdback_xenbus.c,v 1.79 2020/04/19 18:47:40 jdolecek Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -26,7 +26,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.78 2020/04/13 00:27:17 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.79 2020/04/19 18:47:40 jdolecek Exp $");
#include <sys/atomic.h>
#include <sys/buf.h>
@@ -61,19 +61,19 @@ __KERNEL_RCSID(0, "$NetBSD: xbdback_xenb
#define XENPRINTF(x)
#endif
-#define BLKIF_RING_SIZE __RING_SIZE((blkif_sring_t *)0, PAGE_SIZE)
+#define BLKIF_RING_SIZE __CONST_RING_SIZE(blkif, PAGE_SIZE)
/*
* Backend block device driver for Xen
*/
-/* Max number of pages per request. The request may not be page aligned */
-#define BLKIF_MAX_PAGES_PER_REQUEST (BLKIF_MAX_SEGMENTS_PER_REQUEST + 1)
-
/* Values are expressed in 512-byte sectors */
#define VBD_BSIZE 512
#define VBD_MAXSECT ((PAGE_SIZE / VBD_BSIZE) - 1)
+/* Need to alloc one extra page to account for possible mapping offset */
+#define VBD_VA_SIZE (MAXPHYS + PAGE_SIZE)
+
struct xbdback_request;
struct xbdback_io;
struct xbdback_fragment;
@@ -150,6 +150,11 @@ enum xbdi_proto {
XBDIP_64
};
+struct xbdback_va {
+ SLIST_ENTRY(xbdback_va) xv_next;
+ vaddr_t xv_vaddr;
+};
+
/* we keep the xbdback instances in a linked list */
struct xbdback_instance {
SLIST_ENTRY(xbdback_instance) next;
@@ -162,6 +167,9 @@ struct xbdback_instance {
kmutex_t xbdi_lock;
kcondvar_t xbdi_cv; /* wait channel for thread work */
xbdback_state_t xbdi_status; /* thread's status */
+ /* KVA for mapping transfers */
+ struct xbdback_va xbdi_va[BLKIF_RING_SIZE];
+ SLIST_HEAD(, xbdback_va) xbdi_va_free;
/* backing device parameters */
dev_t xbdi_dev;
const struct bdevsw *xbdi_bdevsw; /* pointer to the device's bdevsw */
@@ -185,7 +193,6 @@ struct xbdback_instance {
*/
RING_IDX xbdi_req_prod; /* limit on request indices */
xbdback_cont_t xbdi_cont, xbdi_cont_aux;
- SIMPLEQ_ENTRY(xbdback_instance) xbdi_on_hold; /* waiting on resources */
/* _request state: track requests fetched from ring */
struct xbdback_request *xbdi_req; /* if NULL, ignore following */
blkif_request_t xbdi_xen_req;
@@ -246,6 +253,7 @@ struct xbdback_io {
SLIST_HEAD(, xbdback_fragment) xio_rq;
/* the virtual address to map the request at */
vaddr_t xio_vaddr;
+ struct xbdback_va *xio_xv;
/* grants to map */
grant_ref_t xio_gref[XENSHM_MAX_PAGES_PER_REQUEST];
/* grants release */
@@ -259,6 +267,7 @@ struct xbdback_io {
#define xio_buf u.xio_rw.xio_buf
#define xio_rq u.xio_rw.xio_rq
#define xio_vaddr u.xio_rw.xio_vaddr
+#define xio_xv u.xio_rw.xio_xv
#define xio_gref u.xio_rw.xio_gref
#define xio_gh u.xio_rw.xio_gh
#define xio_nrma u.xio_rw.xio_nrma
@@ -283,20 +292,16 @@ struct xbdback_fragment {
* submitted by frontend.
*/
/* XXXSMP */
-struct xbdback_pool {
+static struct xbdback_pool {
struct pool_cache pc;
struct timeval last_warning;
} xbdback_request_pool, xbdback_io_pool, xbdback_fragment_pool;
-SIMPLEQ_HEAD(xbdback_iqueue, xbdback_instance);
-static struct xbdback_iqueue xbdback_shmq;
-static int xbdback_shmcb; /* have we already registered a callback? */
-
/* Interval between reports of I/O errors from frontend */
-struct timeval xbdback_err_intvl = { 1, 0 };
+static const struct timeval xbdback_err_intvl = { 1, 0 };
#ifdef DEBUG
-struct timeval xbdback_fragio_intvl = { 60, 0 };
+static const struct timeval xbdback_fragio_intvl = { 60, 0 };
#endif
void xbdbackattach(int);
static int xbdback_xenbus_create(struct xenbus_device *);
@@ -333,9 +338,6 @@ static void *xbdback_co_io_gotfrag2(stru
static void *xbdback_co_map_io(struct xbdback_instance *, void *);
static void *xbdback_co_do_io(struct xbdback_instance *, void *);
-static void *xbdback_co_wait_shm_callback(struct xbdback_instance *, void *);
-
-static int xbdback_shm_callback(void *);
static void xbdback_io_error(struct xbdback_io *, int);
static void xbdback_iodone(struct buf *);
static void xbdback_send_reply(struct xbdback_instance *, uint64_t , int , int);
@@ -366,8 +368,6 @@ xbdbackattach(int n)
*/
SLIST_INIT(&xbdback_instances);
mutex_init(&xbdback_lock, MUTEX_DEFAULT, IPL_NONE);
- SIMPLEQ_INIT(&xbdback_shmq);
- xbdback_shmcb = 0;
pool_cache_bootstrap(&xbdback_request_pool.pc,
sizeof(struct xbdback_request), 0, 0, 0, "xbbrp", NULL,
@@ -449,6 +449,13 @@ xbdback_xenbus_create(struct xenbus_devi
xbusd->xbusd_otherend_changed = xbdback_frontend_changed;
xbdi->xbdi_xbusd = xbusd;
+ for (i = 0; i < BLKIF_RING_SIZE; i++) {
+ xbdi->xbdi_va[i].xv_vaddr = uvm_km_alloc(kernel_map,
+ VBD_VA_SIZE, 0, UVM_KMF_VAONLY|UVM_KMF_WAITVA);
+ SLIST_INSERT_HEAD(&xbdi->xbdi_va_free, &xbdi->xbdi_va[i],
+ xv_next);
+ }
+
error = xenbus_watch_path2(xbusd, xbusd->xbusd_path, "physical-device",
&xbdi->xbdi_watch, xbdback_backend_changed);
if (error) {
@@ -515,6 +522,15 @@ xbdback_xenbus_destroy(void *arg)
mutex_enter(&xbdback_lock);
SLIST_REMOVE(&xbdback_instances, xbdi, xbdback_instance, next);
mutex_exit(&xbdback_lock);
+
+ for (int i = 0; i < BLKIF_RING_SIZE; i++) {
+ if (xbdi->xbdi_va[i].xv_vaddr != 0) {
+ uvm_km_free(kernel_map, xbdi->xbdi_va[i].xv_vaddr,
+ VBD_VA_SIZE, UVM_KMF_VAONLY);
+ xbdi->xbdi_va[i].xv_vaddr = 0;
+ }
+ }
+
mutex_destroy(&xbdi->xbdi_lock);
cv_destroy(&xbdi->xbdi_cv);
kmem_free(xbdi, sizeof(*xbdi));
@@ -1406,7 +1422,8 @@ xbdback_co_io_gotio(struct xbdback_insta
xbd_io->xio_operation = xbdi->xbdi_xen_req.operation;
start_offset = xbdi->xbdi_this_fs * VBD_BSIZE;
-
+ KASSERT(start_offset < PAGE_SIZE);
+
if (xbdi->xbdi_xen_req.operation == BLKIF_OP_WRITE) {
buf_flags = B_WRITE;
} else {
@@ -1531,6 +1548,8 @@ static void *
xbdback_co_do_io(struct xbdback_instance *xbdi, void *obj)
{
struct xbdback_io *xbd_io = xbdi->xbdi_io;
+ vaddr_t start_offset;
+ int nsegs __diagused;
switch (xbd_io->xio_operation) {
case BLKIF_OP_FLUSH_DISKCACHE:
@@ -1559,27 +1578,20 @@ xbdback_co_do_io(struct xbdback_instance
}
case BLKIF_OP_READ:
case BLKIF_OP_WRITE:
+ start_offset = (vaddr_t)xbd_io->xio_buf.b_data;
+ KASSERT(xbd_io->xio_buf.b_bcount + start_offset < VDB_VA_SIZE);
xbd_io->xio_buf.b_data = (void *)
- ((vaddr_t)xbd_io->xio_buf.b_data + xbd_io->xio_vaddr);
+ (start_offset + xbd_io->xio_vaddr);
#ifdef DIAGNOSTIC
- {
- vaddr_t bdata = (vaddr_t)xbd_io->xio_buf.b_data;
- int nsegs =
- ((((bdata + xbd_io->xio_buf.b_bcount - 1) & ~PAGE_MASK) -
- (bdata & ~PAGE_MASK)) >> PAGE_SHIFT) + 1;
- if ((bdata & ~PAGE_MASK) != (xbd_io->xio_vaddr & ~PAGE_MASK)) {
- printf("xbdback_co_do_io: vaddr %#" PRIxVADDR
- " bdata %#" PRIxVADDR "\n",
- xbd_io->xio_vaddr, bdata);
- panic("xbdback_co_do_io: bdata page change");
- }
+ nsegs = round_page(start_offset + xbd_io->xio_buf.b_bcount)
+ >> PAGE_SHIFT;
if (nsegs > xbd_io->xio_nrma) {
printf("xbdback_co_do_io: vaddr %#" PRIxVADDR
" bcount %#x doesn't fit in %d pages\n",
- bdata, xbd_io->xio_buf.b_bcount, xbd_io->xio_nrma);
+ start_offset, xbd_io->xio_buf.b_bcount,
+ xbd_io->xio_nrma);
panic("xbdback_co_do_io: not enough pages");
}
- }
#endif
if ((xbd_io->xio_buf.b_flags & B_READ) == 0) {
mutex_enter(xbd_io->xio_buf.b_vp->v_interlock);
@@ -1745,7 +1757,7 @@ xbdback_send_reply(struct xbdback_instan
static void *
xbdback_map_shm(struct xbdback_io *xbd_io)
{
- struct xbdback_instance *xbdi;
+ struct xbdback_instance *xbdi = xbd_io->xio_xbdi;
struct xbdback_request *xbd_rq;
int error, s;
@@ -1759,11 +1771,17 @@ xbdback_map_shm(struct xbdback_io *xbd_i
KASSERT(xbd_io->xio_mapped == 0);
- xbdi = xbd_io->xio_xbdi;
+ s = splvm(); /* XXXSMP */
xbd_rq = SLIST_FIRST(&xbd_io->xio_rq)->car;
+ xbd_io->xio_xv = SLIST_FIRST(&xbdi->xbdi_va_free);
+ KASSERT(xbd_io->xio_xv != NULL);
+ SLIST_REMOVE_HEAD(&xbdi->xbdi_va_free, xv_next);
+ xbd_io->xio_vaddr = xbd_io->xio_xv->xv_vaddr;
+ splx(s);
+
error = xen_shm_map(xbd_io->xio_nrma, xbdi->xbdi_domid,
- xbd_io->xio_gref, &xbd_io->xio_vaddr, xbd_io->xio_gh,
+ xbd_io->xio_gref, xbd_io->xio_vaddr, xbd_io->xio_gh,
(xbd_rq->rq_operation == BLKIF_OP_WRITE) ? XSHM_RO : 0);
switch(error) {
@@ -1777,107 +1795,25 @@ xbdback_map_shm(struct xbdback_io *xbd_i
#endif
xbd_io->xio_mapped = 1;
return xbdi;
- case ENOMEM:
- s = splvm(); /* XXXSMP */
- if (!xbdback_shmcb) {
- if (xen_shm_callback(xbdback_shm_callback, xbdi)
- != 0) {
- splx(s);
- panic("xbdback_map_shm: "
- "xen_shm_callback failed");
- }
- xbdback_shmcb = 1;
- }
- SIMPLEQ_INSERT_TAIL(&xbdback_shmq, xbdi, xbdi_on_hold);
- splx(s);
- /* Put the thread to sleep until the callback is called */
- xbdi->xbdi_cont = xbdback_co_wait_shm_callback;
- return NULL;
default:
if (ratecheck(&xbdi->xbdi_lasterr_time, &xbdback_err_intvl)) {
printf("xbdback_map_shm: xen_shm error %d ", error);
}
xbdback_io_error(xbdi->xbdi_io, error);
+ SLIST_INSERT_HEAD(&xbdi->xbdi_va_free, xbd_io->xio_xv, xv_next);
+ xbd_io->xio_xv = NULL;
xbdi->xbdi_io = NULL;
xbdi->xbdi_cont = xbdi->xbdi_cont_aux;
return xbdi;
}
}
-static int
-xbdback_shm_callback(void *arg)
-{
- int error, s;
-
- /*
- * The shm callback may be executed at any level, including
- * IPL_BIO and IPL_NET levels. Raise to the lowest priority level
- * that can mask both.
- */
- s = splvm(); /* XXXSMP */
- while(!SIMPLEQ_EMPTY(&xbdback_shmq)) {
- struct xbdback_instance *xbdi;
- struct xbdback_io *xbd_io;
- struct xbdback_request *xbd_rq;
-
- xbdi = SIMPLEQ_FIRST(&xbdback_shmq);
- xbd_io = xbdi->xbdi_io;
- xbd_rq = SLIST_FIRST(&xbd_io->xio_rq)->car;
- KASSERT(xbd_io->xio_mapped == 0);
-
- error = xen_shm_map(xbd_io->xio_nrma,
- xbdi->xbdi_domid, xbd_io->xio_gref,
- &xbd_io->xio_vaddr, xbd_io->xio_gh,
- XSHM_CALLBACK |
- ((xbd_rq->rq_operation == BLKIF_OP_WRITE) ? XSHM_RO: 0));
- switch(error) {
- case ENOMEM:
- splx(s);
- return -1; /* will try again later */
- case 0:
- SIMPLEQ_REMOVE_HEAD(&xbdback_shmq, xbdi_on_hold);
- xbd_io->xio_mapped = 1;
- xbdback_wakeup_thread(xbdi);
- break;
- default:
- SIMPLEQ_REMOVE_HEAD(&xbdback_shmq, xbdi_on_hold);
- printf("xbdback_shm_callback: xen_shm error %d\n",
- error);
- xbdback_io_error(xbd_io, error);
- xbdi->xbdi_io = NULL;
- xbdback_wakeup_thread(xbdi);
- break;
- }
- }
- xbdback_shmcb = 0;
- splx(s);
- return 0;
-}
-
-/*
- * Allows waiting for the shm callback to complete.
- */
-static void *
-xbdback_co_wait_shm_callback(struct xbdback_instance *xbdi, void *obj)
-{
-
- if (xbdi->xbdi_io == NULL || xbdi->xbdi_io->xio_mapped == 1) {
- /*
- * Only proceed to next step when the callback reported
- * success or failure.
- */
- xbdi->xbdi_cont = xbdi->xbdi_cont_aux;
- return xbdi;
- } else {
- /* go back to sleep */
- return NULL;
- }
-}
-
/* unmap a request from our virtual address space (request is done) */
static void
xbdback_unmap_shm(struct xbdback_io *xbd_io)
{
+ struct xbdback_instance *xbdi = xbd_io->xio_xbdi;
+
#ifdef XENDEBUG_VBD
int i;
printf("xbdback_unmap_shm handle ");
@@ -1891,6 +1827,8 @@ xbdback_unmap_shm(struct xbdback_io *xbd
xbd_io->xio_mapped = 0;
xen_shm_unmap(xbd_io->xio_vaddr, xbd_io->xio_nrma,
xbd_io->xio_gh);
+ SLIST_INSERT_HEAD(&xbdi->xbdi_va_free, xbd_io->xio_xv, xv_next);
+ xbd_io->xio_xv = NULL;
xbd_io->xio_vaddr = -1;
}
