# HG changeset patch
# User kaf24@xxxxxxxxxxxxxxxxxxxx
# Node ID 944cf29d126d9cdd84f033da9c0f8b1c843b1361
# Parent 6d9ea03c1baa19dfefbbb6ccc7ab43cff2383206
Move arch-specific portions of grant-table implementation
out of common code. Ready for use by ia64.
Signed-off-by: Keir Fraser <keir@xxxxxxxxxxxxx>
diff -r 6d9ea03c1baa -r 944cf29d126d xen/arch/ia64/Makefile
--- a/xen/arch/ia64/Makefile Wed Nov 23 12:38:34 2005
+++ b/xen/arch/ia64/Makefile Wed Nov 23 12:50:14 2005
@@ -10,7 +10,7 @@
extable.o linuxextable.o sort.o xenirq.o xentime.o \
regionreg.o entry.o unaligned.o privop.o vcpu.o \
irq_ia64.o irq_lsapic.o vhpt.o xenasm.o hyperprivop.o dom_fw.o \
- grant_table.o sn_console.o # ia64_ksyms.o
+ sn_console.o # ia64_ksyms.o
OBJS += vmx_init.o vmx_virt.o vmx_vcpu.o vmx_process.o vmx_vsa.o vmx_ivt.o\
vmx_phy_mode.o vmx_utility.o vmx_interrupt.o vmx_entry.o vmmu.o \
diff -r 6d9ea03c1baa -r 944cf29d126d xen/arch/x86/mm.c
--- a/xen/arch/x86/mm.c Wed Nov 23 12:38:34 2005
+++ b/xen/arch/x86/mm.c Wed Nov 23 12:50:14 2005
@@ -2306,7 +2306,7 @@
}
-int update_grant_pte_mapping(
+static int create_grant_pte_mapping(
unsigned long pte_addr, l1_pgentry_t _nl1e, struct vcpu *v)
{
int rc = GNTST_okay;
@@ -2368,7 +2368,7 @@
return rc;
}
-int clear_grant_pte_mapping(
+static int destroy_grant_pte_mapping(
unsigned long addr, unsigned long frame, struct domain *d)
{
int rc = GNTST_okay;
@@ -2445,7 +2445,7 @@
}
-int update_grant_va_mapping(
+static int create_grant_va_mapping(
unsigned long va, l1_pgentry_t _nl1e, struct vcpu *v)
{
l1_pgentry_t *pl1e, ol1e;
@@ -2475,7 +2475,8 @@
return GNTST_okay;
}
-int clear_grant_va_mapping(unsigned long addr, unsigned long frame)
+static int destroy_grant_va_mapping(
+ unsigned long addr, unsigned long frame)
{
l1_pgentry_t *pl1e, ol1e;
@@ -2508,6 +2509,74 @@
return 0;
}
+int create_grant_host_mapping(
+ unsigned long addr, unsigned long frame, unsigned int flags)
+{
+ l1_pgentry_t pte = l1e_from_pfn(frame, GRANT_PTE_FLAGS);
+
+ if ( (flags & GNTMAP_application_map) )
+ l1e_add_flags(pte,_PAGE_USER);
+ if ( !(flags & GNTMAP_readonly) )
+ l1e_add_flags(pte,_PAGE_RW);
+
+ if ( flags & GNTMAP_contains_pte )
+ return create_grant_pte_mapping(addr, pte, current);
+ return create_grant_va_mapping(addr, pte, current);
+}
+
+int destroy_grant_host_mapping(
+ unsigned long addr, unsigned long frame, unsigned int flags)
+{
+ if ( flags & GNTMAP_contains_pte )
+ return destroy_grant_pte_mapping(addr, frame, current->domain);
+ return destroy_grant_va_mapping(addr, frame);
+}
+
+int steal_page_for_grant_transfer(
+ struct domain *d, struct pfn_info *page)
+{
+ u32 _d, _nd, x, y;
+
+ spin_lock(&d->page_alloc_lock);
+
+ /*
+ * The tricky bit: atomically release ownership while there is just one
+ * benign reference to the page (PGC_allocated). If that reference
+ * disappears then the deallocation routine will safely spin.
+ */
+ _d = pickle_domptr(d);
+ _nd = page->u.inuse._domain;
+ y = page->count_info;
+ do {
+ x = y;
+ if (unlikely((x & (PGC_count_mask|PGC_allocated)) !=
+ (1 | PGC_allocated)) || unlikely(_nd != _d)) {
+ DPRINTK("gnttab_transfer: Bad page %p: ed=%p(%u), sd=%p,"
+ " caf=%08x, taf=%" PRtype_info "\n",
+ (void *) page_to_pfn(page),
+ d, d->domain_id, unpickle_domptr(_nd), x,
+ page->u.inuse.type_info);
+ spin_unlock(&d->page_alloc_lock);
+ return -1;
+ }
+ __asm__ __volatile__(
+ LOCK_PREFIX "cmpxchg8b %2"
+ : "=d" (_nd), "=a" (y),
+ "=m" (*(volatile u64 *)(&page->count_info))
+ : "0" (_d), "1" (x), "c" (NULL), "b" (x) );
+ } while (unlikely(_nd != _d) || unlikely(y != x));
+
+ /*
+ * Unlink from 'd'. At least one reference remains (now anonymous), so
+ * noone else is spinning to try to delete this page from 'd'.
+ */
+ d->tot_pages--;
+ list_del(&page->list);
+
+ spin_unlock(&d->page_alloc_lock);
+
+ return 0;
+}
int do_update_va_mapping(unsigned long va, u64 val64,
unsigned long flags)
diff -r 6d9ea03c1baa -r 944cf29d126d xen/common/Makefile
--- a/xen/common/Makefile Wed Nov 23 12:38:34 2005
+++ b/xen/common/Makefile Wed Nov 23 12:50:14 2005
@@ -1,9 +1,5 @@
include $(BASEDIR)/Rules.mk
-
-ifeq ($(TARGET_ARCH),ia64)
-OBJS := $(subst grant_table.o,,$(OBJS))
-endif
ifneq ($(perfc),y)
OBJS := $(subst perfc.o,,$(OBJS))
diff -r 6d9ea03c1baa -r 944cf29d126d xen/common/grant_table.c
--- a/xen/common/grant_table.c Wed Nov 23 12:38:34 2005
+++ b/xen/common/grant_table.c Wed Nov 23 12:50:14 2005
@@ -330,20 +330,7 @@
if ( dev_hst_ro_flags & GNTMAP_host_map )
{
- /* Write update into the pagetable. */
- l1_pgentry_t pte;
- pte = l1e_from_pfn(frame, GRANT_PTE_FLAGS);
-
- if ( (dev_hst_ro_flags & GNTMAP_application_map) )
- l1e_add_flags(pte,_PAGE_USER);
- if ( !(dev_hst_ro_flags & GNTMAP_readonly) )
- l1e_add_flags(pte,_PAGE_RW);
-
- if ( dev_hst_ro_flags & GNTMAP_contains_pte )
- rc = update_grant_pte_mapping(addr, pte, led);
- else
- rc = update_grant_va_mapping(addr, pte, led);
-
+ rc = create_grant_host_mapping(addr, frame, dev_hst_ro_flags);
if ( rc < 0 )
{
/* Failure: undo and abort. */
@@ -488,16 +475,8 @@
(flags & GNTMAP_host_map) &&
((act->pin & (GNTPIN_hstw_mask | GNTPIN_hstr_mask)) > 0))
{
- if ( flags & GNTMAP_contains_pte )
- {
- if ( (rc = clear_grant_pte_mapping(addr, frame, ld)) < 0 )
- goto unmap_out;
- }
- else
- {
- if ( (rc = clear_grant_va_mapping(addr, frame)) < 0 )
- goto unmap_out;
- }
+ if ( (rc = destroy_grant_host_mapping(addr, frame, flags)) < 0 )
+ goto unmap_out;
map->ref_and_flags &= ~GNTMAP_host_map;
@@ -512,9 +491,8 @@
}
/* If just unmapped a writable mapping, mark as dirtied */
- if ( unlikely(shadow_mode_log_dirty(rd)) &&
- !(flags & GNTMAP_readonly) )
- mark_dirty(rd, frame);
+ if ( !(flags & GNTMAP_readonly) )
+ gnttab_log_dirty(rd, frame);
/* If the last writable mapping has been removed, put_page_type */
if ( ((act->pin & (GNTPIN_devw_mask|GNTPIN_hstw_mask)) == 0) &&
@@ -599,9 +577,8 @@
ASSERT(d->grant_table != NULL);
(void)put_user(GNTST_okay, &uop->status);
for ( i = 0; i < op.nr_frames; i++ )
- (void)put_user(
- (virt_to_phys(d->grant_table->shared) >> PAGE_SHIFT) + i,
- &uop->frame_list[i]);
+ (void)put_user(gnttab_shared_mfn(d, d->grant_table, i),
+ &uop->frame_list[i]);
}
put_domain(d);
@@ -698,7 +675,6 @@
struct domain *d = current->domain;
struct domain *e;
struct pfn_info *page;
- u32 _d, _nd, x, y;
int i;
grant_entry_t *sha;
gnttab_transfer_t gop;
@@ -723,46 +699,11 @@
continue;
}
- spin_lock(&d->page_alloc_lock);
-
- /*
- * The tricky bit: atomically release ownership while
- * there is just one benign reference to the page
- * (PGC_allocated). If that reference disappears then the
- * deallocation routine will safely spin.
- */
- _d = pickle_domptr(d);
- _nd = page->u.inuse._domain;
- y = page->count_info;
- do {
- x = y;
- if (unlikely((x & (PGC_count_mask|PGC_allocated)) !=
- (1 | PGC_allocated)) || unlikely(_nd != _d)) {
- DPRINTK("gnttab_transfer: Bad page %p: ed=%p(%u), sd=%p,"
- " caf=%08x, taf=%" PRtype_info "\n",
- (void *) page_to_pfn(page),
- d, d->domain_id, unpickle_domptr(_nd), x,
- page->u.inuse.type_info);
- spin_unlock(&d->page_alloc_lock);
- (void)__put_user(GNTST_bad_page, &uop[i].status);
- continue;
- }
- __asm__ __volatile__(
- LOCK_PREFIX "cmpxchg8b %2"
- : "=d" (_nd), "=a" (y),
- "=m" (*(volatile u64 *)(&page->count_info))
- : "0" (_d), "1" (x), "c" (NULL), "b" (x) );
- } while (unlikely(_nd != _d) || unlikely(y != x));
-
- /*
- * Unlink from 'd'. At least one reference remains (now
- * anonymous), so noone else is spinning to try to delete
- * this page from 'd'.
- */
- d->tot_pages--;
- list_del(&page->list);
-
- spin_unlock(&d->page_alloc_lock);
+ if ( steal_page_for_grant_transfer(d, page) < 0 )
+ {
+ (void)__put_user(GNTST_bad_page, &uop[i].status);
+ continue;
+ }
/* Find the target domain. */
if ( unlikely((e = find_domain_by_id(gop.domid)) == NULL) )
@@ -991,14 +932,7 @@
memset(t->shared, 0, NR_GRANT_FRAMES * PAGE_SIZE);
for ( i = 0; i < NR_GRANT_FRAMES; i++ )
- {
- SHARE_PFN_WITH_DOMAIN(
- virt_to_page((char *)t->shared + (i * PAGE_SIZE)),
- d);
- set_pfn_from_mfn(
- (virt_to_phys(t->shared) >> PAGE_SHIFT) + i,
- INVALID_M2P_ENTRY);
- }
+ gnttab_create_shared_mfn(d, t, i);
/* Okay, install the structure. */
wmb(); /* avoid races with lock-free access to d->grant_table */
diff -r 6d9ea03c1baa -r 944cf29d126d xen/include/asm-x86/mm.h
--- a/xen/include/asm-x86/mm.h Wed Nov 23 12:38:34 2005
+++ b/xen/include/asm-x86/mm.h Wed Nov 23 12:50:14 2005
@@ -381,16 +381,4 @@
extern int __sync_lazy_execstate(void);
-/*
- * Caller must own d's BIGLOCK, is responsible for flushing the TLB, and must
- * hold a reference to the page.
- */
-int update_grant_va_mapping(
- unsigned long va, l1_pgentry_t _nl1e, struct vcpu *v);
-int update_grant_pte_mapping(
- unsigned long pte_addr, l1_pgentry_t _nl1e, struct vcpu *v);
-int clear_grant_va_mapping(unsigned long addr, unsigned long frame);
-int clear_grant_pte_mapping(
- unsigned long addr, unsigned long frame, struct domain *d);
-
#endif /* __ASM_X86_MM_H__ */
diff -r 6d9ea03c1baa -r 944cf29d126d xen/include/xen/grant_table.h
--- a/xen/include/xen/grant_table.h Wed Nov 23 12:38:34 2005
+++ b/xen/include/xen/grant_table.h Wed Nov 23 12:50:14 2005
@@ -4,7 +4,7 @@
* Mechanism for granting foreign access to page frames, and receiving
* page-ownership transfers.
*
- * Copyright (c) 2004 K A Fraser
+ * Copyright (c) 2004-2005 K A Fraser
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -21,11 +21,12 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#ifndef __XEN_GRANT_H__
-#define __XEN_GRANT_H__
+#ifndef __XEN_GRANT_TABLE_H__
+#define __XEN_GRANT_TABLE_H__
#include <xen/config.h>
#include <public/grant_table.h>
+#include <asm/grant_table.h>
/* Active grant entry - used for shadowing GTF_permit_access grants. */
typedef struct {
@@ -51,7 +52,6 @@
#define GNTPIN_devr_inc (1 << GNTPIN_devr_shift)
#define GNTPIN_devr_mask (0xFFU << GNTPIN_devr_shift)
-#define ORDER_GRANT_FRAMES 2
#define NR_GRANT_FRAMES (1U << ORDER_GRANT_FRAMES)
#define NR_GRANT_ENTRIES \
((NR_GRANT_FRAMES << PAGE_SHIFT) / sizeof(grant_entry_t))
@@ -107,4 +107,4 @@
gnttab_release_mappings(
struct domain *d);
-#endif /* __XEN_GRANT_H__ */
+#endif /* __XEN_GRANT_TABLE_H__ */
diff -r 6d9ea03c1baa -r 944cf29d126d xen/include/asm-ia64/grant_table.h
--- /dev/null Wed Nov 23 12:38:34 2005
+++ b/xen/include/asm-ia64/grant_table.h Wed Nov 23 12:50:14 2005
@@ -0,0 +1,26 @@
+/******************************************************************************
+ * include/asm-ia64/grant_table.h
+ */
+
+#ifndef __ASM_GRANT_TABLE_H__
+#define __ASM_GRANT_TABLE_H__
+
+#define ORDER_GRANT_FRAMES 0
+
+#define create_grant_host_mapping(a, f, fl) 0
+#define destroy_grant_host_mapping(a, f, fl) 0
+
+#define steal_page_for_grant_transfer(d, p) 0
+
+#define gnttab_create_shared_mfn(d, t, i) ((void)0)
+
+#define gnttab_shared_mfn(d, t, i) \
+ ( ((d) == dom0) ? \
+ ((virt_to_phys((t)shared) >> PAGE_SHIFT) + (i)) : \
+ (map_domain_page((d), 1UL<<40, virt_to_phys((t)->shared)), \
+ 1UL << (40 - PAGE_SHIFT)) \
+ )
+
+#define gnttab_log_dirty(d, f) ((void)0)
+
+#endif /* __ASM_GRANT_TABLE_H__ */
diff -r 6d9ea03c1baa -r 944cf29d126d xen/include/asm-x86/grant_table.h
--- /dev/null Wed Nov 23 12:38:34 2005
+++ b/xen/include/asm-x86/grant_table.h Wed Nov 23 12:50:14 2005
@@ -0,0 +1,42 @@
+/******************************************************************************
+ * include/asm-x86/grant_table.h
+ *
+ * Copyright (c) 2004-2005 K A Fraser
+ */
+
+#ifndef __ASM_GRANT_TABLE_H__
+#define __ASM_GRANT_TABLE_H__
+
+#define ORDER_GRANT_FRAMES 2
+
+/*
+ * Caller must own caller's BIGLOCK, is responsible for flushing the TLB, and
+ * must hold a reference to the page.
+ */
+int create_grant_host_mapping(
+ unsigned long addr, unsigned long frame, unsigned int flags);
+int destroy_grant_host_mapping(
+ unsigned long addr, unsigned long frame, unsigned int flags);
+
+int steal_page_for_grant_transfer(
+ struct domain *d, struct pfn_info *page);
+
+#define gnttab_create_shared_mfn(d, t, i) \
+ do { \
+ SHARE_PFN_WITH_DOMAIN( \
+ virt_to_page((char *)(t)->shared + ((i) * PAGE_SIZE)), (d)); \
+ set_pfn_from_mfn( \
+ (virt_to_phys((t)->shared) >> PAGE_SHIFT) + (i), \
+ INVALID_M2P_ENTRY); \
+ } while ( 0 )
+
+#define gnttab_shared_mfn(d, t, i) \
+ ((virt_to_phys((t)->shared) >> PAGE_SHIFT) + (i))
+
+#define gnttab_log_dirty(d, f) \
+ do { \
+ if ( unlikely(shadow_mode_log_dirty((d))) ) \
+ mark_dirty((d), (f)); \
+ } while ( 0 )
+
+#endif /* __ASM_GRANT_TABLE_H__ */
diff -r 6d9ea03c1baa -r 944cf29d126d xen/arch/ia64/xen/grant_table.c
--- a/xen/arch/ia64/xen/grant_table.c Wed Nov 23 12:38:34 2005
+++ /dev/null Wed Nov 23 12:50:14 2005
@@ -1,1354 +0,0 @@
-// temporarily in arch/ia64 until can merge into common/grant_table.c
-/******************************************************************************
- * common/grant_table.c
- *
- * Mechanism for granting foreign access to page frames, and receiving
- * page-ownership transfers.
- *
- * Copyright (c) 2005 Christopher Clark
- * Copyright (c) 2004 K A Fraser
- * Copyright (c) 2005 Andrew Warfield
- * Modifications by Geoffrey Lefebvre are (c) Intel Research Cambridge
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#define GRANT_DEBUG 0
-#define GRANT_DEBUG_VERBOSE 0
-
-#include <xen/config.h>
-#include <xen/lib.h>
-#include <xen/sched.h>
-#include <xen/shadow.h>
-#include <xen/mm.h>
-#ifdef __ia64__
-#define __addr_ok(a) 1 // FIXME-ia64: a variant of access_ok??
-// FIXME-ia64: these belong in an asm/grant_table.h... PAGE_SIZE different
-#undef ORDER_GRANT_FRAMES
-//#undef NUM_GRANT_FRAMES
-#define ORDER_GRANT_FRAMES 0
-//#define NUM_GRANT_FRAMES (1U << ORDER_GRANT_FRAMES)
-#endif
-#include <acm/acm_hooks.h>
-
-#if defined(CONFIG_X86_64)
-#define GRANT_PTE_FLAGS (_PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_DIRTY|_PAGE_USER)
-#else
-#define GRANT_PTE_FLAGS (_PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_DIRTY)
-#endif
-
-#define PIN_FAIL(_lbl, _rc, _f, _a...) \
- do { \
- DPRINTK( _f, ## _a ); \
- rc = (_rc); \
- goto _lbl; \
- } while ( 0 )
-
-static inline int
-get_maptrack_handle(
- grant_table_t *t)
-{
- unsigned int h;
- if ( unlikely((h = t->maptrack_head) == (t->maptrack_limit - 1)) )
- return -1;
- t->maptrack_head = t->maptrack[h].ref_and_flags >> MAPTRACK_REF_SHIFT;
- t->map_count++;
- return h;
-}
-
-static inline void
-put_maptrack_handle(
- grant_table_t *t, int handle)
-{
- t->maptrack[handle].ref_and_flags = t->maptrack_head << MAPTRACK_REF_SHIFT;
- t->maptrack_head = handle;
- t->map_count--;
-}
-
-static int
-__gnttab_activate_grant_ref(
- struct domain *mapping_d, /* IN */
- struct vcpu *mapping_ed,
- struct domain *granting_d,
- grant_ref_t ref,
- u16 dev_hst_ro_flags,
- u64 addr,
- unsigned long *pframe ) /* OUT */
-{
- domid_t sdom;
- u16 sflags;
- active_grant_entry_t *act;
- grant_entry_t *sha;
- s16 rc = 1;
- unsigned long frame = 0;
- int retries = 0;
-
- /*
- * Objectives of this function:
- * . Make the record ( granting_d, ref ) active, if not already.
- * . Update shared grant entry of owner, indicating frame is mapped.
- * . Increment the owner act->pin reference counts.
- * . get_page on shared frame if new mapping.
- * . get_page_type if this is first RW mapping of frame.
- * . Add PTE to virtual address space of mapping_d, if necessary.
- * Returns:
- * . -ve: error
- * . 1: ok
- * . 0: ok and TLB invalidate of host_addr needed.
- *
- * On success, *pframe contains mfn.
- */
-
- /*
- * We bound the number of times we retry CMPXCHG on memory locations that
- * we share with a guest OS. The reason is that the guest can modify that
- * location at a higher rate than we can read-modify-CMPXCHG, so the guest
- * could cause us to livelock. There are a few cases where it is valid for
- * the guest to race our updates (e.g., to change the GTF_readonly flag),
- * so we allow a few retries before failing.
- */
-
- act = &granting_d->grant_table->active[ref];
- sha = &granting_d->grant_table->shared[ref];
-
- spin_lock(&granting_d->grant_table->lock);
-
- if ( act->pin == 0 )
- {
- /* CASE 1: Activating a previously inactive entry. */
-
- sflags = sha->flags;
- sdom = sha->domid;
-
- /* This loop attempts to set the access (reading/writing) flags
- * in the grant table entry. It tries a cmpxchg on the field
- * up to five times, and then fails under the assumption that
- * the guest is misbehaving. */
- for ( ; ; )
- {
- u32 scombo, prev_scombo, new_scombo;
-
- if ( unlikely((sflags & GTF_type_mask) != GTF_permit_access) ||
- unlikely(sdom != mapping_d->domain_id) )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Bad flags (%x) or dom (%d). (NB. expected dom %d)\n",
- sflags, sdom, mapping_d->domain_id);
-
- /* Merge two 16-bit values into a 32-bit combined update. */
- /* NB. Endianness! */
- prev_scombo = scombo = ((u32)sdom << 16) | (u32)sflags;
-
- new_scombo = scombo | GTF_reading;
- if ( !(dev_hst_ro_flags & GNTMAP_readonly) )
- {
- new_scombo |= GTF_writing;
- if ( unlikely(sflags & GTF_readonly) )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Attempt to write-pin a r/o grant entry.\n");
- }
-
- /* NB. prev_scombo is updated in place to seen value. */
- if ( unlikely(cmpxchg_user((u32 *)&sha->flags,
- prev_scombo,
- new_scombo)) )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Fault while modifying shared flags and domid.\n");
-
- /* Did the combined update work (did we see what we expected?). */
- if ( likely(prev_scombo == scombo) )
- break;
-
- if ( retries++ == 4 )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Shared grant entry is unstable.\n");
-
- /* Didn't see what we expected. Split out the seen flags & dom. */
- /* NB. Endianness! */
- sflags = (u16)prev_scombo;
- sdom = (u16)(prev_scombo >> 16);
- }
-
- /* rmb(); */ /* not on x86 */
-
- frame = __gpfn_to_mfn_foreign(granting_d, sha->frame);
-
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here?
-#else
- if ( unlikely(!pfn_valid(frame)) ||
- unlikely(!((dev_hst_ro_flags & GNTMAP_readonly) ?
- get_page(&frame_table[frame], granting_d) :
- get_page_and_type(&frame_table[frame], granting_d,
- PGT_writable_page))) )
- {
- clear_bit(_GTF_writing, &sha->flags);
- clear_bit(_GTF_reading, &sha->flags);
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Could not pin the granted frame (%lx)!\n", frame);
- }
-#endif
-
- if ( dev_hst_ro_flags & GNTMAP_device_map )
- act->pin += (dev_hst_ro_flags & GNTMAP_readonly) ?
- GNTPIN_devr_inc : GNTPIN_devw_inc;
- if ( dev_hst_ro_flags & GNTMAP_host_map )
- act->pin += (dev_hst_ro_flags & GNTMAP_readonly) ?
- GNTPIN_hstr_inc : GNTPIN_hstw_inc;
- act->domid = sdom;
- act->frame = frame;
- }
- else
- {
- /* CASE 2: Active modications to an already active entry. */
-
- /*
- * A cheesy check for possible pin-count overflow.
- * A more accurate check cannot be done with a single comparison.
- */
- if ( (act->pin & 0x80808080U) != 0 )
- PIN_FAIL(unlock_out, ENOSPC,
- "Risk of counter overflow %08x\n", act->pin);
-
- frame = act->frame;
-
- if ( !(dev_hst_ro_flags & GNTMAP_readonly) &&
- !((sflags = sha->flags) & GTF_writing) )
- {
- for ( ; ; )
- {
- u16 prev_sflags;
-
- if ( unlikely(sflags & GTF_readonly) )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Attempt to write-pin a r/o grant entry.\n");
-
- prev_sflags = sflags;
-
- /* NB. prev_sflags is updated in place to seen value. */
- if ( unlikely(cmpxchg_user(&sha->flags, prev_sflags,
- prev_sflags | GTF_writing)) )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Fault while modifying shared flags.\n");
-
- if ( likely(prev_sflags == sflags) )
- break;
-
- if ( retries++ == 4 )
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Shared grant entry is unstable.\n");
-
- sflags = prev_sflags;
- }
-
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here?
-#else
- if ( unlikely(!get_page_type(&frame_table[frame],
- PGT_writable_page)) )
- {
- clear_bit(_GTF_writing, &sha->flags);
- PIN_FAIL(unlock_out, GNTST_general_error,
- "Attempt to write-pin a unwritable page.\n");
- }
-#endif
- }
-
- if ( dev_hst_ro_flags & GNTMAP_device_map )
- act->pin += (dev_hst_ro_flags & GNTMAP_readonly) ?
- GNTPIN_devr_inc : GNTPIN_devw_inc;
-
- if ( dev_hst_ro_flags & GNTMAP_host_map )
- act->pin += (dev_hst_ro_flags & GNTMAP_readonly) ?
- GNTPIN_hstr_inc : GNTPIN_hstw_inc;
- }
-
- /*
- * At this point:
- * act->pin updated to reference count mappings.
- * sha->flags updated to indicate to granting domain mapping done.
- * frame contains the mfn.
- */
-
- spin_unlock(&granting_d->grant_table->lock);
-
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here?
-#else
- if ( (addr != 0) && (dev_hst_ro_flags & GNTMAP_host_map) )
- {
- /* Write update into the pagetable. */
- l1_pgentry_t pte;
- pte = l1e_from_pfn(frame, GRANT_PTE_FLAGS);
-
- if ( (dev_hst_ro_flags & GNTMAP_application_map) )
- l1e_add_flags(pte,_PAGE_USER);
- if ( !(dev_hst_ro_flags & GNTMAP_readonly) )
- l1e_add_flags(pte,_PAGE_RW);
-
- if ( dev_hst_ro_flags & GNTMAP_contains_pte )
- rc = update_grant_pte_mapping(addr, pte, mapping_d, mapping_ed);
- else
- rc = update_grant_va_mapping(addr, pte, mapping_d, mapping_ed);
-
- /* IMPORTANT: rc indicates the degree of TLB flush that is required.
- * GNTST_flush_one (1) or GNTST_flush_all (2). This is done in the
- * outer gnttab_map_grant_ref. */
- if ( rc < 0 )
- {
- /* Failure: undo and abort. */
-
- spin_lock(&granting_d->grant_table->lock);
-
- if ( dev_hst_ro_flags & GNTMAP_readonly )
- {
- act->pin -= GNTPIN_hstr_inc;
- }
- else
- {
- act->pin -= GNTPIN_hstw_inc;
- if ( (act->pin & (GNTPIN_hstw_mask|GNTPIN_devw_mask)) == 0 )
- {
- clear_bit(_GTF_writing, &sha->flags);
- put_page_type(&frame_table[frame]);
- }
- }
-
- if ( act->pin == 0 )
- {
- clear_bit(_GTF_reading, &sha->flags);
- put_page(&frame_table[frame]);
- }
-
- spin_unlock(&granting_d->grant_table->lock);
- }
-
- }
-#endif
-
- *pframe = frame;
- return rc;
-
- unlock_out:
- spin_unlock(&granting_d->grant_table->lock);
- return rc;
-}
-
-/*
- * Returns 0 if TLB flush / invalidate required by caller.
- * va will indicate the address to be invalidated.
- *
- * addr is _either_ a host virtual address, or the address of the pte to
- * update, as indicated by the GNTMAP_contains_pte flag.
- */
-static int
-__gnttab_map_grant_ref(
- gnttab_map_grant_ref_t *uop,
- unsigned long *va)
-{
- domid_t dom;
- grant_ref_t ref;
- struct domain *ld, *rd;
- struct vcpu *led;
- u16 dev_hst_ro_flags;
- int handle;
- u64 addr;
- unsigned long frame = 0;
- int rc;
-
- led = current;
- ld = led->domain;
-
- /* Bitwise-OR avoids short-circuiting which screws control flow. */
- if ( unlikely(__get_user(dom, &uop->dom) |
- __get_user(ref, &uop->ref) |
- __get_user(addr, &uop->host_addr) |
- __get_user(dev_hst_ro_flags, &uop->flags)) )
- {
- DPRINTK("Fault while reading gnttab_map_grant_ref_t.\n");
- return -EFAULT; /* don't set status */
- }
-
- if ( (dev_hst_ro_flags & GNTMAP_host_map) &&
- ( (addr == 0) ||
- (!(dev_hst_ro_flags & GNTMAP_contains_pte) &&
- unlikely(!__addr_ok(addr))) ) )
- {
- DPRINTK("Bad virtual address (%"PRIx64") or flags (%"PRIx16").\n",
- addr, dev_hst_ro_flags);
- (void)__put_user(GNTST_bad_virt_addr, &uop->handle);
- return GNTST_bad_gntref;
- }
-
- if ( unlikely(ref >= NR_GRANT_ENTRIES) ||
- unlikely((dev_hst_ro_flags &
- (GNTMAP_device_map|GNTMAP_host_map)) == 0) )
- {
- DPRINTK("Bad ref (%d) or flags (%x).\n", ref, dev_hst_ro_flags);
- (void)__put_user(GNTST_bad_gntref, &uop->handle);
- return GNTST_bad_gntref;
- }
-
- if (acm_pre_grant_map_ref(dom)) {
- (void)__put_user(GNTST_permission_denied, &uop->handle);
- return GNTST_permission_denied;
- }
-
- if ( unlikely((rd = find_domain_by_id(dom)) == NULL) ||
- unlikely(ld == rd) )
- {
- if ( rd != NULL )
- put_domain(rd);
- DPRINTK("Could not find domain %d\n", dom);
- (void)__put_user(GNTST_bad_domain, &uop->handle);
- return GNTST_bad_domain;
- }
-
- /* Get a maptrack handle. */
- if ( unlikely((handle = get_maptrack_handle(ld->grant_table)) == -1) )
- {
- int i;
- grant_mapping_t *new_mt;
- grant_table_t *lgt = ld->grant_table;
-
- if ( (lgt->maptrack_limit << 1) > MAPTRACK_MAX_ENTRIES )
- {
- put_domain(rd);
- DPRINTK("Maptrack table is at maximum size.\n");
- (void)__put_user(GNTST_no_device_space, &uop->handle);
- return GNTST_no_device_space;
- }
-
- /* Grow the maptrack table. */
- new_mt = alloc_xenheap_pages(lgt->maptrack_order + 1);
- if ( new_mt == NULL )
- {
- put_domain(rd);
- DPRINTK("No more map handles available.\n");
- (void)__put_user(GNTST_no_device_space, &uop->handle);
- return GNTST_no_device_space;
- }
-
- memcpy(new_mt, lgt->maptrack, PAGE_SIZE << lgt->maptrack_order);
- for ( i = lgt->maptrack_limit; i < (lgt->maptrack_limit << 1); i++ )
- new_mt[i].ref_and_flags = (i+1) << MAPTRACK_REF_SHIFT;
-
- free_xenheap_pages(lgt->maptrack, lgt->maptrack_order);
- lgt->maptrack = new_mt;
- lgt->maptrack_order += 1;
- lgt->maptrack_limit <<= 1;
-
- DPRINTK("Doubled maptrack size\n");
- handle = get_maptrack_handle(ld->grant_table);
- }
-
-#if GRANT_DEBUG_VERBOSE
- DPRINTK("Mapping grant ref (%hu) for domain (%hu) with flags (%x)\n",
- ref, dom, dev_hst_ro_flags);
-#endif
-
- if ( 0 <= ( rc = __gnttab_activate_grant_ref( ld, led, rd, ref,
- dev_hst_ro_flags,
- addr, &frame)))
- {
- /*
- * Only make the maptrack live _after_ writing the pte, in case we
- * overwrite the same frame number, causing a maptrack walk to find it
- */
- ld->grant_table->maptrack[handle].domid = dom;
-
- ld->grant_table->maptrack[handle].ref_and_flags
- = (ref << MAPTRACK_REF_SHIFT) |
- (dev_hst_ro_flags & MAPTRACK_GNTMAP_MASK);
-
- (void)__put_user((u64)frame << PAGE_SHIFT, &uop->dev_bus_addr);
-
- if ( ( dev_hst_ro_flags & GNTMAP_host_map ) &&
- !( dev_hst_ro_flags & GNTMAP_contains_pte) )
- *va = addr;
-
- (void)__put_user(handle, &uop->handle);
- }
- else
- {
- (void)__put_user(rc, &uop->handle);
- put_maptrack_handle(ld->grant_table, handle);
- }
-
- put_domain(rd);
- return rc;
-}
-
-static long
-gnttab_map_grant_ref(
- gnttab_map_grant_ref_t *uop, unsigned int count)
-{
- int i, rc, flush = 0;
- unsigned long va = 0;
-
- for ( i = 0; i < count; i++ )
- if ( (rc =__gnttab_map_grant_ref(&uop[i], &va)) >= 0 )
- flush += rc;
-
-#ifdef __ia64__
-// FIXME-ia64: probably need to do something here to avoid stale mappings?
-#else
- if ( flush == 1 )
- flush_tlb_one_mask(current->domain->cpumask, va);
- else if ( flush != 0 )
- flush_tlb_mask(current->domain->cpumask);
-#endif
-
- return 0;
-}
-
-static int
-__gnttab_unmap_grant_ref(
- gnttab_unmap_grant_ref_t *uop,
- unsigned long *va)
-{
- domid_t dom;
- grant_ref_t ref;
- u16 handle;
- struct domain *ld, *rd;
- active_grant_entry_t *act;
- grant_entry_t *sha;
- grant_mapping_t *map;
- u16 flags;
- s16 rc = 1;
- u64 addr, dev_bus_addr;
- unsigned long frame;
-
- ld = current->domain;
-
- /* Bitwise-OR avoids short-circuiting which screws control flow. */
- if ( unlikely(__get_user(addr, &uop->host_addr) |
- __get_user(dev_bus_addr, &uop->dev_bus_addr) |
- __get_user(handle, &uop->handle)) )
- {
- DPRINTK("Fault while reading gnttab_unmap_grant_ref_t.\n");
- return -EFAULT; /* don't set status */
- }
-
- frame = (unsigned long)(dev_bus_addr >> PAGE_SHIFT);
-
- map = &ld->grant_table->maptrack[handle];
-
- if ( unlikely(handle >= ld->grant_table->maptrack_limit) ||
- unlikely(!(map->ref_and_flags & MAPTRACK_GNTMAP_MASK)) )
- {
- DPRINTK("Bad handle (%d).\n", handle);
- (void)__put_user(GNTST_bad_handle, &uop->status);
- return GNTST_bad_handle;
- }
-
- dom = map->domid;
- ref = map->ref_and_flags >> MAPTRACK_REF_SHIFT;
- flags = map->ref_and_flags & MAPTRACK_GNTMAP_MASK;
-
- if ( unlikely((rd = find_domain_by_id(dom)) == NULL) ||
- unlikely(ld == rd) )
- {
- if ( rd != NULL )
- put_domain(rd);
- DPRINTK("Could not find domain %d\n", dom);
- (void)__put_user(GNTST_bad_domain, &uop->status);
- return GNTST_bad_domain;
- }
-
-#if GRANT_DEBUG_VERBOSE
- DPRINTK("Unmapping grant ref (%hu) for domain (%hu) with handle (%hu)\n",
- ref, dom, handle);
-#endif
-
- act = &rd->grant_table->active[ref];
- sha = &rd->grant_table->shared[ref];
-
- spin_lock(&rd->grant_table->lock);
-
- if ( frame == 0 )
- {
- frame = act->frame;
- }
- else
- {
- if ( unlikely(frame != act->frame) )
- PIN_FAIL(unmap_out, GNTST_general_error,
- "Bad frame number doesn't match gntref.\n");
- if ( flags & GNTMAP_device_map )
- act->pin -= (flags & GNTMAP_readonly) ? GNTPIN_devr_inc
- : GNTPIN_devw_inc;
-
- map->ref_and_flags &= ~GNTMAP_device_map;
- (void)__put_user(0, &uop->dev_bus_addr);
-
- /* Frame is now unmapped for device access. */
- }
-
- if ( (addr != 0) &&
- (flags & GNTMAP_host_map) &&
- ((act->pin & (GNTPIN_hstw_mask | GNTPIN_hstr_mask)) > 0))
- {
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here?
-#else
- if ( flags & GNTMAP_contains_pte )
- {
- if ( (rc = clear_grant_pte_mapping(addr, frame, ld)) < 0 )
- goto unmap_out;
- }
- else
- {
- if ( (rc = clear_grant_va_mapping(addr, frame)) < 0 )
- goto unmap_out;
- }
-#endif
-
- map->ref_and_flags &= ~GNTMAP_host_map;
-
- act->pin -= (flags & GNTMAP_readonly) ? GNTPIN_hstr_inc
- : GNTPIN_hstw_inc;
-
- rc = 0;
- if ( !( flags & GNTMAP_contains_pte) )
- *va = addr;
- }
-
- if ( (map->ref_and_flags & (GNTMAP_device_map|GNTMAP_host_map)) == 0)
- {
- map->ref_and_flags = 0;
- put_maptrack_handle(ld->grant_table, handle);
- }
-
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here? I think not and then
-// this can probably be macro-ized into nothingness
-#else
- /* If just unmapped a writable mapping, mark as dirtied */
- if ( unlikely(shadow_mode_log_dirty(rd)) &&
- !( flags & GNTMAP_readonly ) )
- mark_dirty(rd, frame);
-#endif
-
- /* If the last writable mapping has been removed, put_page_type */
- if ( ( (act->pin & (GNTPIN_devw_mask|GNTPIN_hstw_mask) ) == 0) &&
- ( !( flags & GNTMAP_readonly ) ) )
- {
- clear_bit(_GTF_writing, &sha->flags);
- put_page_type(&frame_table[frame]);
- }
-
- if ( act->pin == 0 )
- {
- act->frame = 0xdeadbeef;
- clear_bit(_GTF_reading, &sha->flags);
- put_page(&frame_table[frame]);
- }
-
- unmap_out:
- (void)__put_user(rc, &uop->status);
- spin_unlock(&rd->grant_table->lock);
- put_domain(rd);
- return rc;
-}
-
-static long
-gnttab_unmap_grant_ref(
- gnttab_unmap_grant_ref_t *uop, unsigned int count)
-{
- int i, flush = 0;
- unsigned long va = 0;
-
- for ( i = 0; i < count; i++ )
- if ( __gnttab_unmap_grant_ref(&uop[i], &va) == 0 )
- flush++;
-
-#ifdef __ia64__
-// FIXME-ia64: probably need to do something here to avoid stale mappings?
-#else
- if ( flush == 1 )
- flush_tlb_one_mask(current->domain->cpumask, va);
- else if ( flush != 0 )
- flush_tlb_mask(current->domain->cpumask);
-#endif
-
- return 0;
-}
-
-static long
-gnttab_setup_table(
- gnttab_setup_table_t *uop, unsigned int count)
-{
- gnttab_setup_table_t op;
- struct domain *d;
- int i;
-
- if ( count != 1 )
- return -EINVAL;
-
- if ( unlikely(copy_from_user(&op, uop, sizeof(op)) != 0) )
- {
- DPRINTK("Fault while reading gnttab_setup_table_t.\n");
- return -EFAULT;
- }
-
- if ( unlikely(op.nr_frames > NR_GRANT_FRAMES) )
- {
- DPRINTK("Xen only supports up to %d grant-table frames per domain.\n",
- NR_GRANT_FRAMES);
- (void)put_user(GNTST_general_error, &uop->status);
- return 0;
- }
-
- if ( op.dom == DOMID_SELF )
- {
- op.dom = current->domain->domain_id;
- }
- else if ( unlikely(!IS_PRIV(current->domain)) )
- {
- (void)put_user(GNTST_permission_denied, &uop->status);
- return 0;
- }
-
- if ( unlikely((d = find_domain_by_id(op.dom)) == NULL) )
- {
- DPRINTK("Bad domid %d.\n", op.dom);
- (void)put_user(GNTST_bad_domain, &uop->status);
- return 0;
- }
-
- if ( op.nr_frames <= NR_GRANT_FRAMES )
- {
- ASSERT(d->grant_table != NULL);
- (void)put_user(GNTST_okay, &uop->status);
-#ifdef __ia64__
- if (d == dom0) {
- for ( i = 0; i < op.nr_frames; i++ )
- (void)put_user(
- (virt_to_phys(d->grant_table->shared) >> PAGE_SHIFT) + i,
- &uop->frame_list[i]);
- } else {
- /* IA64 hack - need to map it somewhere */
- unsigned long addr = (1UL << 40);
- map_domain_page(d, addr, virt_to_phys(d->grant_table->shared));
- (void)put_user(addr >> PAGE_SHIFT, &uop->frame_list[0]);
- }
-#else
- for ( i = 0; i < op.nr_frames; i++ )
- (void)put_user(
- (virt_to_phys(d->grant_table->shared) >> PAGE_SHIFT) + i,
- &uop->frame_list[i]);
-#endif
- }
-
- put_domain(d);
- return 0;
-}
-
-#if GRANT_DEBUG
-static int
-gnttab_dump_table(gnttab_dump_table_t *uop)
-{
- grant_table_t *gt;
- gnttab_dump_table_t op;
- struct domain *d;
- u32 shared_mfn;
- active_grant_entry_t *act;
- grant_entry_t sha_copy;
- grant_mapping_t *maptrack;
- int i;
-
-
- if ( unlikely(copy_from_user(&op, uop, sizeof(op)) != 0) )
- {
- DPRINTK("Fault while reading gnttab_dump_table_t.\n");
- return -EFAULT;
- }
-
- if ( op.dom == DOMID_SELF )
- {
- op.dom = current->domain->domain_id;
- }
-
- if ( unlikely((d = find_domain_by_id(op.dom)) == NULL) )
- {
- DPRINTK("Bad domid %d.\n", op.dom);
- (void)put_user(GNTST_bad_domain, &uop->status);
- return 0;
- }
-
- ASSERT(d->grant_table != NULL);
- gt = d->grant_table;
- (void)put_user(GNTST_okay, &uop->status);
-
- shared_mfn = virt_to_phys(d->grant_table->shared);
-
- DPRINTK("Grant table for dom (%hu) MFN (%x)\n",
- op.dom, shared_mfn);
-
- ASSERT(d->grant_table->active != NULL);
- ASSERT(d->grant_table->shared != NULL);
- ASSERT(d->grant_table->maptrack != NULL);
-
- for ( i = 0; i < NR_GRANT_ENTRIES; i++ )
- {
- sha_copy = gt->shared[i];
-
- if ( sha_copy.flags )
- {
- DPRINTK("Grant: dom (%hu) SHARED (%d) flags:(%hx) "
- "dom:(%hu) frame:(%x)\n",
- op.dom, i, sha_copy.flags, sha_copy.domid, sha_copy.frame);
- }
- }
-
- spin_lock(>->lock);
-
- for ( i = 0; i < NR_GRANT_ENTRIES; i++ )
- {
- act = >->active[i];
-
- if ( act->pin )
- {
- DPRINTK("Grant: dom (%hu) ACTIVE (%d) pin:(%x) "
- "dom:(%hu) frame:(%lx)\n",
- op.dom, i, act->pin, act->domid, act->frame);
- }
- }
-
- for ( i = 0; i < gt->maptrack_limit; i++ )
- {
- maptrack = >->maptrack[i];
-
- if ( maptrack->ref_and_flags & MAPTRACK_GNTMAP_MASK )
- {
- DPRINTK("Grant: dom (%hu) MAP (%d) ref:(%hu) flags:(%x) "
- "dom:(%hu)\n",
- op.dom, i,
- maptrack->ref_and_flags >> MAPTRACK_REF_SHIFT,
- maptrack->ref_and_flags & MAPTRACK_GNTMAP_MASK,
- maptrack->domid);
- }
- }
-
- spin_unlock(>->lock);
-
- put_domain(d);
- return 0;
-}
-#endif
-
-static long
-gnttab_transfer(gnttab_transfer_t *uop, unsigned int count)
-{
- struct domain *d = current->domain;
- struct domain *e;
- struct pfn_info *page;
- u32 _d, _nd, x, y;
- int i;
- int result = GNTST_okay;
-
-#ifdef __ia64__
-//FIXME-IA64: not support for now?
- return GNTST_general_error;
-#else
- for (i = 0; i < count; i++) {
- gnttab_transfer_t *gop = &uop[i];
-#if GRANT_DEBUG
- printk("gnttab_transfer: i=%d mfn=%lx domid=%d gref=%08x\n",
- i, gop->mfn, gop->domid, gop->handle);
-#endif
- page = &frame_table[gop->mfn];
-
- if (unlikely(IS_XEN_HEAP_FRAME(page))) {
- printk("gnttab_transfer: xen heap frame mfn=%lx\n",
- (unsigned long) gop->mfn);
- gop->status = GNTST_bad_virt_addr;
- continue;
- }
- if (unlikely(!pfn_valid(page_to_pfn(page)))) {
- printk("gnttab_transfer: invalid pfn for mfn=%lx\n",
- (unsigned long) gop->mfn);
- gop->status = GNTST_bad_virt_addr;
- continue;
- }
- if (unlikely((e = find_domain_by_id(gop->domid)) == NULL)) {
- printk("gnttab_transfer: can't find domain %d\n", gop->domid);
- gop->status = GNTST_bad_domain;
- continue;
- }
-
- spin_lock(&d->page_alloc_lock);
-
- /*
- * The tricky bit: atomically release ownership while
- * there is just one benign reference to the page
- * (PGC_allocated). If that reference disappears then the
- * deallocation routine will safely spin.
- */
- _d = pickle_domptr(d);
- _nd = page->u.inuse._domain;
- y = page->count_info;
- do {
- x = y;
- if (unlikely((x & (PGC_count_mask|PGC_allocated)) !=
- (1 | PGC_allocated)) || unlikely(_nd != _d)) {
- printk("gnttab_transfer: Bad page values %p: ed=%p(%u), sd=%p,"
- " caf=%08x, taf=%" PRtype_info "\n",
- (void *) page_to_pfn(page),
- d, d->domain_id, unpickle_domptr(_nd), x,
- page->u.inuse.type_info);
- spin_unlock(&d->page_alloc_lock);
- put_domain(e);
- return 0;
- }
- __asm__ __volatile__(
- LOCK_PREFIX "cmpxchg8b %2"
- : "=d" (_nd), "=a" (y),
- "=m" (*(volatile u64 *)(&page->count_info))
- : "0" (_d), "1" (x), "c" (NULL), "b" (x) );
- } while (unlikely(_nd != _d) || unlikely(y != x));
-
- /*
- * Unlink from 'd'. At least one reference remains (now
- * anonymous), so noone else is spinning to try to delete
- * this page from 'd'.
- */
- d->tot_pages--;
- list_del(&page->list);
-
- spin_unlock(&d->page_alloc_lock);
-
- spin_lock(&e->page_alloc_lock);
-
- /*
- * Check that 'e' will accept the page and has reservation
- * headroom. Also, a domain mustn't have PGC_allocated
- * pages when it is dying.
- */
-#ifdef GRANT_DEBUG
- if (unlikely(e->tot_pages >= e->max_pages)) {
- printk("gnttab_dontate: no headroom tot_pages=%d max_pages=%d\n",
- e->tot_pages, e->max_pages);
- spin_unlock(&e->page_alloc_lock);
- put_domain(e);
- result = GNTST_general_error;
- break;
- }
- if (unlikely(test_bit(DOMFLAGS_DYING, &e->domain_flags))) {
- printk("gnttab_transfer: target domain is dying\n");
- spin_unlock(&e->page_alloc_lock);
- put_domain(e);
- result = GNTST_general_error;
- break;
- }
- if (unlikely(!gnttab_prepare_for_transfer(e, d, gop->ref))) {
- printk("gnttab_transfer: gnttab_prepare_for_transfer fails\n");
- spin_unlock(&e->page_alloc_lock);
- put_domain(e);
- result = GNTST_general_error;
- break;
- }
-#else
- ASSERT(e->tot_pages <= e->max_pages);
- if (unlikely(test_bit(DOMFLAGS_DYING, &e->domain_flags)) ||
- unlikely(e->tot_pages == e->max_pages) ||
- unlikely(!gnttab_prepare_for_transfer(e, d, gop->ref))) {
- printk("gnttab_transfer: Transferee has no reservation headroom
(%d,"
- "%d) or provided a bad grant ref (%08x) or is dying (%p)\n",
- e->tot_pages, e->max_pages, gop->ref, e->d_flags);
- spin_unlock(&e->page_alloc_lock);
- put_domain(e);
- result = GNTST_general_error;
- break;
- }
-#endif
- /* Okay, add the page to 'e'. */
- if (unlikely(e->tot_pages++ == 0)) {
- get_knownalive_domain(e);
- }
- list_add_tail(&page->list, &e->page_list);
- page_set_owner(page, e);
-
- spin_unlock(&e->page_alloc_lock);
-
- /*
- * Transfer is all done: tell the guest about its new page
- * frame.
- */
- gnttab_notify_transfer(e, d, gop->ref, gop->mfn);
-
- put_domain(e);
-
- gop->status = GNTST_okay;
- }
- return result;
-#endif
-}
-
-long
-do_grant_table_op(
- unsigned int cmd, void *uop, unsigned int count)
-{
- long rc;
- struct domain *d = current->domain;
-
- if ( count > 512 )
- return -EINVAL;
-
- LOCK_BIGLOCK(d);
-
-#ifndef __ia64__
- sync_pagetable_state(d);
-#endif
-
- rc = -EFAULT;
- switch ( cmd )
- {
- case GNTTABOP_map_grant_ref:
- if ( unlikely(!array_access_ok(
- uop, count, sizeof(gnttab_map_grant_ref_t))) )
- goto out;
- rc = gnttab_map_grant_ref((gnttab_map_grant_ref_t *)uop, count);
- break;
- case GNTTABOP_unmap_grant_ref:
- if ( unlikely(!array_access_ok(
- uop, count, sizeof(gnttab_unmap_grant_ref_t))) )
- goto out;
- rc = gnttab_unmap_grant_ref((gnttab_unmap_grant_ref_t *)uop,
- count);
- break;
- case GNTTABOP_setup_table:
- rc = gnttab_setup_table((gnttab_setup_table_t *)uop, count);
- break;
-#if GRANT_DEBUG
- case GNTTABOP_dump_table:
- rc = gnttab_dump_table((gnttab_dump_table_t *)uop);
- break;
-#endif
- case GNTTABOP_transfer:
- if (unlikely(!array_access_ok(uop, count,
- sizeof(gnttab_transfer_t))))
- goto out;
- rc = gnttab_transfer(uop, count);
- break;
- default:
- rc = -ENOSYS;
- break;
- }
-
- out:
- UNLOCK_BIGLOCK(d);
-
- return rc;
-}
-
-int
-gnttab_prepare_for_transfer(
- struct domain *rd, struct domain *ld, grant_ref_t ref)
-{
- grant_table_t *rgt;
- grant_entry_t *sha;
- domid_t sdom;
- u16 sflags;
- u32 scombo, prev_scombo;
- int retries = 0;
- unsigned long target_pfn;
-
-#if GRANT_DEBUG_VERBOSE
- DPRINTK("gnttab_prepare_for_transfer rd(%hu) ld(%hu) ref(%hu).\n",
- rd->domain_id, ld->domain_id, ref);
-#endif
-
- if ( unlikely((rgt = rd->grant_table) == NULL) ||
- unlikely(ref >= NR_GRANT_ENTRIES) )
- {
- DPRINTK("Dom %d has no g.t., or ref is bad (%d).\n",
- rd->domain_id, ref);
- return 0;
- }
-
- spin_lock(&rgt->lock);
-
- sha = &rgt->shared[ref];
-
- sflags = sha->flags;
- sdom = sha->domid;
-
- for ( ; ; )
- {
- target_pfn = sha->frame;
-
- if ( unlikely(target_pfn >= max_page ) )
- {
- DPRINTK("Bad pfn (%lx)\n", target_pfn);
- goto fail;
- }
-
- if ( unlikely(sflags != GTF_accept_transfer) ||
- unlikely(sdom != ld->domain_id) )
- {
- DPRINTK("Bad flags (%x) or dom (%d). (NB. expected dom %d)\n",
- sflags, sdom, ld->domain_id);
- goto fail;
- }
-
- /* Merge two 16-bit values into a 32-bit combined update. */
- /* NB. Endianness! */
- prev_scombo = scombo = ((u32)sdom << 16) | (u32)sflags;
-
- /* NB. prev_scombo is updated in place to seen value. */
- if ( unlikely(cmpxchg_user((u32 *)&sha->flags, prev_scombo,
- prev_scombo | GTF_transfer_committed)) )
- {
- DPRINTK("Fault while modifying shared flags and domid.\n");
- goto fail;
- }
-
- /* Did the combined update work (did we see what we expected?). */
- if ( likely(prev_scombo == scombo) )
- break;
-
- if ( retries++ == 4 )
- {
- DPRINTK("Shared grant entry is unstable.\n");
- goto fail;
- }
-
- /* Didn't see what we expected. Split out the seen flags & dom. */
- /* NB. Endianness! */
- sflags = (u16)prev_scombo;
- sdom = (u16)(prev_scombo >> 16);
- }
-
- spin_unlock(&rgt->lock);
- return 1;
-
- fail:
- spin_unlock(&rgt->lock);
- return 0;
-}
-
-void
-gnttab_notify_transfer(
- struct domain *rd, struct domain *ld, grant_ref_t ref, unsigned long frame)
-{
- grant_entry_t *sha;
- unsigned long pfn;
-
-#if GRANT_DEBUG_VERBOSE
- DPRINTK("gnttab_notify_transfer rd(%hu) ld(%hu) ref(%hu).\n",
- rd->domain_id, ld->domain_id, ref);
-#endif
-
- sha = &rd->grant_table->shared[ref];
-
- spin_lock(&rd->grant_table->lock);
-
-#ifdef __ia64__
-// FIXME-ia64: any error checking need to be done here?
-#else
- pfn = sha->frame;
-
- if ( unlikely(pfn >= max_page ) )
- DPRINTK("Bad pfn (%lx)\n", pfn);
- else
- {
- machine_to_phys_mapping[frame] = pfn;
-
- if ( unlikely(shadow_mode_log_dirty(ld)))
- mark_dirty(ld, frame);
-
- if (shadow_mode_translate(ld))
- __phys_to_machine_mapping[pfn] = frame;
- }
-#endif
- sha->frame = __mfn_to_gpfn(rd, frame);
- sha->domid = rd->domain_id;
- wmb();
- sha->flags = ( GTF_accept_transfer | GTF_transfer_completed );
-
- spin_unlock(&rd->grant_table->lock);
-
- return;
-}
-
-int
-grant_table_create(
- struct domain *d)
-{
- grant_table_t *t;
- int i;
-
- if ( (t = xmalloc(grant_table_t)) == NULL )
- goto no_mem;
-
- /* Simple stuff. */
- memset(t, 0, sizeof(*t));
- spin_lock_init(&t->lock);
-
- /* Active grant table. */
- if ( (t->active = xmalloc_array(active_grant_entry_t, NR_GRANT_ENTRIES))
- == NULL )
- goto no_mem;
- memset(t->active, 0, sizeof(active_grant_entry_t) * NR_GRANT_ENTRIES);
-
- /* Tracking of mapped foreign frames table */
- if ( (t->maptrack = alloc_xenheap_page()) == NULL )
- goto no_mem;
- t->maptrack_order = 0;
- t->maptrack_limit = PAGE_SIZE / sizeof(grant_mapping_t);
- memset(t->maptrack, 0, PAGE_SIZE);
- for ( i = 0; i < t->maptrack_limit; i++ )
- t->maptrack[i].ref_and_flags = (i+1) << MAPTRACK_REF_SHIFT;
-
- /* Shared grant table. */
- t->shared = alloc_xenheap_pages(ORDER_GRANT_FRAMES);
- if ( t->shared == NULL )
- goto no_mem;
- memset(t->shared, 0, NR_GRANT_FRAMES * PAGE_SIZE);
-
-#ifdef __ia64__
-// I don't think there's anything to do here on ia64?...
-#else
- for ( i = 0; i < NR_GRANT_FRAMES; i++ )
- {
- SHARE_PFN_WITH_DOMAIN(
- virt_to_page((char *)(t->shared)+(i*PAGE_SIZE)), d);
- machine_to_phys_mapping[(virt_to_phys(t->shared) >> PAGE_SHIFT) + i] =
- INVALID_M2P_ENTRY;
- }
-#endif
-
- /* Okay, install the structure. */
- wmb(); /* avoid races with lock-free access to d->grant_table */
- d->grant_table = t;
- return 0;
-
- no_mem:
- if ( t != NULL )
- {
- xfree(t->active);
- free_xenheap_page(t->maptrack);
- xfree(t);
- }
- return -ENOMEM;
-}
-
-void
-gnttab_release_mappings(
- struct domain *ld)
-{
- grant_table_t *gt = ld->grant_table;
- grant_mapping_t *map;
- domid_t dom;
- grant_ref_t ref;
- u16 handle;
- struct domain *ld, *rd;
- unsigned long frame;
- active_grant_entry_t *act;
- grant_entry_t *sha;
-
- for ( handle = 0; handle < gt->maptrack_limit; handle++ )
- {
- map = >->maptrack[handle];
-
- if ( map->ref_and_flags & GNTMAP_device_map )
- {
- dom = map->domid;
- ref = map->ref_and_flags >> MAPTRACK_REF_SHIFT;
-
- DPRINTK("Grant release (%hu) ref:(%hu) flags:(%x) dom:(%hu)\n",
- handle, ref,
- map->ref_and_flags & MAPTRACK_GNTMAP_MASK, dom);
-
- if ( unlikely((rd = find_domain_by_id(dom)) == NULL) ||
- unlikely(ld == rd) )
- {
- if ( rd != NULL )
- put_domain(rd);
-
- printk(KERN_WARNING "Grant release: No dom%d\n", dom);
- continue;
- }
-
- act = &rd->grant_table->active[ref];
- sha = &rd->grant_table->shared[ref];
-
- spin_lock(&rd->grant_table->lock);
-
- if ( act->pin & (GNTPIN_devw_mask | GNTPIN_devr_mask) )
- {
- frame = act->frame;
-
- if ( ( (act->pin & GNTPIN_hstw_mask) == 0 ) &&
- ( (act->pin & GNTPIN_devw_mask) > 0 ) )
- {
- clear_bit(_GTF_writing, &sha->flags);
- put_page_type(&frame_table[frame]);
- }
-
- act->pin &= ~(GNTPIN_devw_mask | GNTPIN_devr_mask);
-
- if ( act->pin == 0 )
- {
- clear_bit(_GTF_reading, &sha->flags);
- map->ref_and_flags = 0;
- put_page(&frame_table[frame]);
- }
- else
- map->ref_and_flags &= ~GNTMAP_device_map;
- }
-
- spin_unlock(&rd->grant_table->lock);
-
- put_domain(rd);
- }
- }
-}
-
-
-void
-grant_table_destroy(
- struct domain *d)
-{
- grant_table_t *t;
-
- if ( (t = d->grant_table) != NULL )
- {
- /* Free memory relating to this grant table. */
- d->grant_table = NULL;
- free_xenheap_pages(t->shared, ORDER_GRANT_FRAMES);
- free_xenheap_page(t->maptrack);
- xfree(t->active);
- xfree(t);
- }
-}
-
-void
-grant_table_init(
- void)
-{
- /* Nothing. */
-}
-
-/*
- * Local variables:
- * mode: C
- * c-set-style: "BSD"
- * c-basic-offset: 4
- * tab-width: 4
- * indent-tabs-mode: nil
- * End:
- */
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