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intel-iommu: add IOTLB using hash table
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Add IOTLB to cache information about the translation of input-addresses. IOTLB
use a GHashTable as cache. The key of the hash table is the logical-OR of gfn
and source id after left-shifting.

Signed-off-by: Le Tan <tamlokveer@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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@tamlok @mstsirkin
tamlok authored and mstsirkin committed Aug 28, 2014
1 parent d92fa2d commit b5a280c
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Showing 3 changed files with 251 additions and 7 deletions.
213 changes: 208 additions & 5 deletions hw/i386/intel_iommu.c
View file
Expand Up @@ -132,6 +132,35 @@ static uint64_t vtd_set_clear_mask_quad(IntelIOMMUState *s, hwaddr addr,
return new_val;
}

/* GHashTable functions */
static gboolean vtd_uint64_equal(gconstpointer v1, gconstpointer v2)
{
return *((const uint64_t *)v1) == *((const uint64_t *)v2);
}

static guint vtd_uint64_hash(gconstpointer v)
{
return (guint)*(const uint64_t *)v;
}

static gboolean vtd_hash_remove_by_domain(gpointer key, gpointer value,
gpointer user_data)
{
VTDIOTLBEntry *entry = (VTDIOTLBEntry *)value;
uint16_t domain_id = *(uint16_t *)user_data;
return entry->domain_id == domain_id;
}

static gboolean vtd_hash_remove_by_page(gpointer key, gpointer value,
gpointer user_data)
{
VTDIOTLBEntry *entry = (VTDIOTLBEntry *)value;
VTDIOTLBPageInvInfo *info = (VTDIOTLBPageInvInfo *)user_data;
uint64_t gfn = info->gfn & info->mask;
return (entry->domain_id == info->domain_id) &&
((entry->gfn & info->mask) == gfn);
}

/* Reset all the gen of VTDAddressSpace to zero and set the gen of
* IntelIOMMUState to 1.
*/
Expand Down Expand Up @@ -159,6 +188,48 @@ static void vtd_reset_context_cache(IntelIOMMUState *s)
s->context_cache_gen = 1;
}

static void vtd_reset_iotlb(IntelIOMMUState *s)
{
assert(s->iotlb);
g_hash_table_remove_all(s->iotlb);
}

static VTDIOTLBEntry *vtd_lookup_iotlb(IntelIOMMUState *s, uint16_t source_id,
hwaddr addr)
{
uint64_t key;

key = (addr >> VTD_PAGE_SHIFT_4K) |
((uint64_t)(source_id) << VTD_IOTLB_SID_SHIFT);
return g_hash_table_lookup(s->iotlb, &key);

}

static void vtd_update_iotlb(IntelIOMMUState *s, uint16_t source_id,
uint16_t domain_id, hwaddr addr, uint64_t slpte,
bool read_flags, bool write_flags)
{
VTDIOTLBEntry *entry = g_malloc(sizeof(*entry));
uint64_t *key = g_malloc(sizeof(*key));
uint64_t gfn = addr >> VTD_PAGE_SHIFT_4K;

VTD_DPRINTF(CACHE, "update iotlb sid 0x%"PRIx16 " gpa 0x%"PRIx64
" slpte 0x%"PRIx64 " did 0x%"PRIx16, source_id, addr, slpte,
domain_id);
if (g_hash_table_size(s->iotlb) >= VTD_IOTLB_MAX_SIZE) {
VTD_DPRINTF(CACHE, "iotlb exceeds size limit, forced to reset");
vtd_reset_iotlb(s);
}

entry->gfn = gfn;
entry->domain_id = domain_id;
entry->slpte = slpte;
entry->read_flags = read_flags;
entry->write_flags = write_flags;
*key = gfn | ((uint64_t)(source_id) << VTD_IOTLB_SID_SHIFT);
g_hash_table_replace(s->iotlb, key, entry);
}

/* Given the reg addr of both the message data and address, generate an
* interrupt via MSI.
*/
Expand Down Expand Up @@ -693,6 +764,7 @@ static void vtd_do_iommu_translate(VTDAddressSpace *vtd_as, uint8_t bus_num,
bool is_fpd_set = false;
bool reads = true;
bool writes = true;
VTDIOTLBEntry *iotlb_entry;

/* Check if the request is in interrupt address range */
if (vtd_is_interrupt_addr(addr)) {
Expand All @@ -716,6 +788,17 @@ static void vtd_do_iommu_translate(VTDAddressSpace *vtd_as, uint8_t bus_num,
return;
}
}
/* Try to fetch slpte form IOTLB */
iotlb_entry = vtd_lookup_iotlb(s, source_id, addr);
if (iotlb_entry) {
VTD_DPRINTF(CACHE, "hit iotlb sid 0x%"PRIx16 " gpa 0x%"PRIx64
" slpte 0x%"PRIx64 " did 0x%"PRIx16, source_id, addr,
iotlb_entry->slpte, iotlb_entry->domain_id);
slpte = iotlb_entry->slpte;
reads = iotlb_entry->read_flags;
writes = iotlb_entry->write_flags;
goto out;
}
/* Try to fetch context-entry from cache first */
if (cc_entry->context_cache_gen == s->context_cache_gen) {
VTD_DPRINTF(CACHE, "hit context-cache bus %d devfn %d "
Expand Down Expand Up @@ -760,6 +843,9 @@ static void vtd_do_iommu_translate(VTDAddressSpace *vtd_as, uint8_t bus_num,
return;
}

vtd_update_iotlb(s, source_id, VTD_CONTEXT_ENTRY_DID(ce.hi), addr, slpte,
reads, writes);
out:
entry->iova = addr & VTD_PAGE_MASK_4K;
entry->translated_addr = vtd_get_slpte_addr(slpte) & VTD_PAGE_MASK_4K;
entry->addr_mask = ~VTD_PAGE_MASK_4K;
Expand Down Expand Up @@ -859,6 +945,29 @@ static uint64_t vtd_context_cache_invalidate(IntelIOMMUState *s, uint64_t val)
return caig;
}

static void vtd_iotlb_global_invalidate(IntelIOMMUState *s)
{
vtd_reset_iotlb(s);
}

static void vtd_iotlb_domain_invalidate(IntelIOMMUState *s, uint16_t domain_id)
{
g_hash_table_foreach_remove(s->iotlb, vtd_hash_remove_by_domain,
&domain_id);
}

static void vtd_iotlb_page_invalidate(IntelIOMMUState *s, uint16_t domain_id,
hwaddr addr, uint8_t am)
{
VTDIOTLBPageInvInfo info;

assert(am <= VTD_MAMV);
info.domain_id = domain_id;
info.gfn = addr >> VTD_PAGE_SHIFT_4K;
info.mask = ~((1 << am) - 1);
g_hash_table_foreach_remove(s->iotlb, vtd_hash_remove_by_page, &info);
}

/* Flush IOTLB
* Returns the IOTLB Actual Invalidation Granularity.
* @val: the content of the IOTLB_REG
Expand All @@ -867,25 +976,44 @@ static uint64_t vtd_iotlb_flush(IntelIOMMUState *s, uint64_t val)
{
uint64_t iaig;
uint64_t type = val & VTD_TLB_FLUSH_GRANU_MASK;
uint16_t domain_id;
hwaddr addr;
uint8_t am;

switch (type) {
case VTD_TLB_GLOBAL_FLUSH:
VTD_DPRINTF(INV, "Global IOTLB flush");
VTD_DPRINTF(INV, "global invalidation");
iaig = VTD_TLB_GLOBAL_FLUSH_A;
vtd_iotlb_global_invalidate(s);
break;

case VTD_TLB_DSI_FLUSH:
VTD_DPRINTF(INV, "Domain-selective IOTLB flush");
domain_id = VTD_TLB_DID(val);
VTD_DPRINTF(INV, "domain-selective invalidation domain 0x%"PRIx16,
domain_id);
iaig = VTD_TLB_DSI_FLUSH_A;
vtd_iotlb_domain_invalidate(s, domain_id);
break;

case VTD_TLB_PSI_FLUSH:
VTD_DPRINTF(INV, "Page-selective-within-domain IOTLB flush");
domain_id = VTD_TLB_DID(val);
addr = vtd_get_quad_raw(s, DMAR_IVA_REG);
am = VTD_IVA_AM(addr);
addr = VTD_IVA_ADDR(addr);
VTD_DPRINTF(INV, "page-selective invalidation domain 0x%"PRIx16
" addr 0x%"PRIx64 " mask %"PRIu8, domain_id, addr, am);
if (am > VTD_MAMV) {
VTD_DPRINTF(GENERAL, "error: supported max address mask value is "
"%"PRIu8, (uint8_t)VTD_MAMV);
iaig = 0;
break;
}
iaig = VTD_TLB_PSI_FLUSH_A;
vtd_iotlb_page_invalidate(s, domain_id, addr, am);
break;

default:
VTD_DPRINTF(GENERAL, "error: wrong iotlb flush granularity");
VTD_DPRINTF(GENERAL, "error: invalid granularity");
iaig = 0;
}
return iaig;
Expand Down Expand Up @@ -1123,6 +1251,56 @@ static bool vtd_process_context_cache_desc(IntelIOMMUState *s,
return true;
}

static bool vtd_process_iotlb_desc(IntelIOMMUState *s, VTDInvDesc *inv_desc)
{
uint16_t domain_id;
uint8_t am;
hwaddr addr;

if ((inv_desc->lo & VTD_INV_DESC_IOTLB_RSVD_LO) ||
(inv_desc->hi & VTD_INV_DESC_IOTLB_RSVD_HI)) {
VTD_DPRINTF(GENERAL, "error: non-zero reserved field in IOTLB "
"Invalidate Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
inv_desc->hi, inv_desc->lo);
return false;
}

switch (inv_desc->lo & VTD_INV_DESC_IOTLB_G) {
case VTD_INV_DESC_IOTLB_GLOBAL:
VTD_DPRINTF(INV, "global invalidation");
vtd_iotlb_global_invalidate(s);
break;

case VTD_INV_DESC_IOTLB_DOMAIN:
domain_id = VTD_INV_DESC_IOTLB_DID(inv_desc->lo);
VTD_DPRINTF(INV, "domain-selective invalidation domain 0x%"PRIx16,
domain_id);
vtd_iotlb_domain_invalidate(s, domain_id);
break;

case VTD_INV_DESC_IOTLB_PAGE:
domain_id = VTD_INV_DESC_IOTLB_DID(inv_desc->lo);
addr = VTD_INV_DESC_IOTLB_ADDR(inv_desc->hi);
am = VTD_INV_DESC_IOTLB_AM(inv_desc->hi);
VTD_DPRINTF(INV, "page-selective invalidation domain 0x%"PRIx16
" addr 0x%"PRIx64 " mask %"PRIu8, domain_id, addr, am);
if (am > VTD_MAMV) {
VTD_DPRINTF(GENERAL, "error: supported max address mask value is "
"%"PRIu8, (uint8_t)VTD_MAMV);
return false;
}
vtd_iotlb_page_invalidate(s, domain_id, addr, am);
break;

default:
VTD_DPRINTF(GENERAL, "error: invalid granularity in IOTLB Invalidate "
"Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
inv_desc->hi, inv_desc->lo);
return false;
}
return true;
}

static bool vtd_process_inv_desc(IntelIOMMUState *s)
{
VTDInvDesc inv_desc;
Expand All @@ -1149,6 +1327,9 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
case VTD_INV_DESC_IOTLB:
VTD_DPRINTF(INV, "IOTLB Invalidate Descriptor hi 0x%"PRIx64
" lo 0x%"PRIx64, inv_desc.hi, inv_desc.lo);
if (!vtd_process_iotlb_desc(s, &inv_desc)) {
return false;
}
break;

case VTD_INV_DESC_WAIT:
Expand Down Expand Up @@ -1382,6 +1563,24 @@ static void vtd_mem_write(void *opaque, hwaddr addr,
vtd_handle_iotlb_write(s);
break;

/* Invalidate Address Register, 64-bit */
case DMAR_IVA_REG:
VTD_DPRINTF(INV, "DMAR_IVA_REG write addr 0x%"PRIx64
", size %d, val 0x%"PRIx64, addr, size, val);
if (size == 4) {
vtd_set_long(s, addr, val);
} else {
vtd_set_quad(s, addr, val);
}
break;

case DMAR_IVA_REG_HI:
VTD_DPRINTF(INV, "DMAR_IVA_REG_HI write addr 0x%"PRIx64
", size %d, val 0x%"PRIx64, addr, size, val);
assert(size == 4);
vtd_set_long(s, addr, val);
break;

/* Fault Status Register, 32-bit */
case DMAR_FSTS_REG:
VTD_DPRINTF(FLOG, "DMAR_FSTS_REG write addr 0x%"PRIx64
Expand Down Expand Up @@ -1658,10 +1857,11 @@ static void vtd_init(IntelIOMMUState *s)
s->iq_last_desc_type = VTD_INV_DESC_NONE;
s->next_frcd_reg = 0;
s->cap = VTD_CAP_FRO | VTD_CAP_NFR | VTD_CAP_ND | VTD_CAP_MGAW |
VTD_CAP_SAGAW;
VTD_CAP_SAGAW | VTD_CAP_MAMV | VTD_CAP_PSI;
s->ecap = VTD_ECAP_QI | VTD_ECAP_IRO;

vtd_reset_context_cache(s);
vtd_reset_iotlb(s);

/* Define registers with default values and bit semantics */
vtd_define_long(s, DMAR_VER_REG, 0x10UL, 0, 0);
Expand Down Expand Up @@ -1731,6 +1931,9 @@ static void vtd_realize(DeviceState *dev, Error **errp)
memory_region_init_io(&s->csrmem, OBJECT(s), &vtd_mem_ops, s,
"intel_iommu", DMAR_REG_SIZE);
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->csrmem);
/* No corresponding destroy */
s->iotlb = g_hash_table_new_full(vtd_uint64_hash, vtd_uint64_equal,
g_free, g_free);
vtd_init(s);
}

Expand Down
34 changes: 33 additions & 1 deletion hw/i386/intel_iommu_internal.h
View file
Expand Up @@ -111,6 +111,10 @@
#define VTD_INTERRUPT_ADDR_FIRST 0xfee00000ULL
#define VTD_INTERRUPT_ADDR_LAST 0xfeefffffULL

/* The shift of source_id in the key of IOTLB hash table */
#define VTD_IOTLB_SID_SHIFT 36
#define VTD_IOTLB_MAX_SIZE 1024 /* Max size of the hash table */

/* IOTLB_REG */
#define VTD_TLB_GLOBAL_FLUSH (1ULL << 60) /* Global invalidation */
#define VTD_TLB_DSI_FLUSH (2ULL << 60) /* Domain-selective */
Expand All @@ -121,6 +125,11 @@
#define VTD_TLB_PSI_FLUSH_A (3ULL << 57)
#define VTD_TLB_FLUSH_GRANU_MASK_A (3ULL << 57)
#define VTD_TLB_IVT (1ULL << 63)
#define VTD_TLB_DID(val) (((val) >> 32) & VTD_DOMAIN_ID_MASK)

/* IVA_REG */
#define VTD_IVA_ADDR(val) ((val) & ~0xfffULL & ((1ULL << VTD_MGAW) - 1))
#define VTD_IVA_AM(val) ((val) & 0x3fULL)

/* GCMD_REG */
#define VTD_GCMD_TE (1UL << 31)
Expand Down Expand Up @@ -176,6 +185,9 @@
#define VTD_CAP_ND (((VTD_DOMAIN_ID_SHIFT - 4) / 2) & 7ULL)
#define VTD_MGAW 39 /* Maximum Guest Address Width */
#define VTD_CAP_MGAW (((VTD_MGAW - 1) & 0x3fULL) << 16)
#define VTD_MAMV 9ULL
#define VTD_CAP_MAMV (VTD_MAMV << 48)
#define VTD_CAP_PSI (1ULL << 39)

/* Supported Adjusted Guest Address Widths */
#define VTD_CAP_SAGAW_SHIFT 8
Expand Down Expand Up @@ -293,6 +305,26 @@ typedef struct VTDInvDesc VTDInvDesc;
#define VTD_INV_DESC_CC_FM(val) (((val) >> 48) & 3UL)
#define VTD_INV_DESC_CC_RSVD 0xfffc00000000ffc0ULL

/* Masks for IOTLB Invalidate Descriptor */
#define VTD_INV_DESC_IOTLB_G (3ULL << 4)
#define VTD_INV_DESC_IOTLB_GLOBAL (1ULL << 4)
#define VTD_INV_DESC_IOTLB_DOMAIN (2ULL << 4)
#define VTD_INV_DESC_IOTLB_PAGE (3ULL << 4)
#define VTD_INV_DESC_IOTLB_DID(val) (((val) >> 16) & VTD_DOMAIN_ID_MASK)
#define VTD_INV_DESC_IOTLB_ADDR(val) ((val) & ~0xfffULL & \
((1ULL << VTD_MGAW) - 1))
#define VTD_INV_DESC_IOTLB_AM(val) ((val) & 0x3fULL)
#define VTD_INV_DESC_IOTLB_RSVD_LO 0xffffffff0000ff00ULL
#define VTD_INV_DESC_IOTLB_RSVD_HI 0xf80ULL

/* Information about page-selective IOTLB invalidate */
struct VTDIOTLBPageInvInfo {
uint16_t domain_id;
uint64_t gfn;
uint8_t mask;
};
typedef struct VTDIOTLBPageInvInfo VTDIOTLBPageInvInfo;

/* Pagesize of VTD paging structures, including root and context tables */
#define VTD_PAGE_SHIFT 12
#define VTD_PAGE_SIZE (1ULL << VTD_PAGE_SHIFT)
Expand Down Expand Up @@ -330,7 +362,7 @@ typedef struct VTDRootEntry VTDRootEntry;
#define VTD_CONTEXT_ENTRY_RSVD_LO (0xff0ULL | ~VTD_HAW_MASK)
/* hi */
#define VTD_CONTEXT_ENTRY_AW 7ULL /* Adjusted guest-address-width */
#define VTD_CONTEXT_ENTRY_DID (0xffffULL << 8) /* Domain Identifier */
#define VTD_CONTEXT_ENTRY_DID(val) (((val) >> 8) & VTD_DOMAIN_ID_MASK)
#define VTD_CONTEXT_ENTRY_RSVD_HI 0xffffffffff000080ULL

#define VTD_CONTEXT_ENTRY_NR (VTD_PAGE_SIZE / sizeof(VTDContextEntry))
Expand Down

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