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From: Shashi Mallela <shashi.mallela@linaro.org>
To: peter.maydell@linaro.org, leif@nuviainc.com, rad@semihalf.com,
	mst@redhat.com, imammedo@redhat.com
Cc: qemu-arm@nongnu.org, qemu-devel@nongnu.org
Subject: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing
Date: Wed, 30 Jun 2021 11:31:50 -0400	[thread overview]
Message-ID: <20210630153156.9421-5-shashi.mallela@linaro.org> (raw)
In-Reply-To: <20210630153156.9421-1-shashi.mallela@linaro.org>

Added ITS command queue handling for MAPTI,MAPI commands,handled ITS
translation which triggers an LPI via INT command as well as write
to GITS_TRANSLATER register,defined enum to differentiate between ITS
command interrupt trigger and GITS_TRANSLATER based interrupt trigger.
Each of these commands make use of other functionalities implemented to
get device table entry,collection table entry or interrupt translation
table entry required for their processing.

Signed-off-by: Shashi Mallela <shashi.mallela@linaro.org>
---
 hw/intc/arm_gicv3_its.c            | 361 ++++++++++++++++++++++++++++-
 hw/intc/gicv3_internal.h           |  26 +++
 include/hw/intc/arm_gicv3_common.h |   2 +
 3 files changed, 388 insertions(+), 1 deletion(-)

diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 5919d8d7b1..adaee72c1f 100644
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -28,6 +28,22 @@ struct GICv3ITSClass {
     void (*parent_reset)(DeviceState *dev);
 };
 
+/*
+ * This is an internal enum used to distinguish between LPI triggered
+ * via command queue and LPI triggered via gits_translater write.
+ */
+typedef enum ItsCmdType {
+    NONE = 0, /* internal indication for GITS_TRANSLATER write */
+    CLEAR = 1,
+    DISCARD = 2,
+    INT = 3,
+} ItsCmdType;
+
+typedef struct {
+    uint32_t iteh;
+    uint64_t itel;
+} IteEntry;
+
 static uint64_t baser_base_addr(uint64_t value, uint32_t page_sz)
 {
     uint64_t result = 0;
@@ -49,6 +65,330 @@ static uint64_t baser_base_addr(uint64_t value, uint32_t page_sz)
     return result;
 }
 
+static bool get_cte(GICv3ITSState *s, uint16_t icid, uint64_t *cte,
+                    MemTxResult *res)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint64_t l2t_addr;
+    uint64_t value;
+    bool valid_l2t;
+    uint32_t l2t_id;
+    uint32_t max_l2_entries;
+
+    if (s->ct.indirect) {
+        l2t_id = icid / (s->ct.page_sz / L1TABLE_ENTRY_SIZE);
+
+        value = address_space_ldq_le(as,
+                                     s->ct.base_addr +
+                                     (l2t_id * L1TABLE_ENTRY_SIZE),
+                                     MEMTXATTRS_UNSPECIFIED, res);
+
+        if (*res == MEMTX_OK) {
+            valid_l2t = (value & L2_TABLE_VALID_MASK) != 0;
+
+            if (valid_l2t) {
+                max_l2_entries = s->ct.page_sz / s->ct.entry_sz;
+
+                l2t_addr = value & ((1ULL << 51) - 1);
+
+                *cte =  address_space_ldq_le(as, l2t_addr +
+                                    ((icid % max_l2_entries) * GITS_CTE_SIZE),
+                                    MEMTXATTRS_UNSPECIFIED, res);
+           }
+       }
+    } else {
+        /* Flat level table */
+        *cte =  address_space_ldq_le(as, s->ct.base_addr +
+                                     (icid * GITS_CTE_SIZE),
+                                      MEMTXATTRS_UNSPECIFIED, res);
+    }
+
+    return (*cte & TABLE_ENTRY_VALID_MASK) != 0;
+}
+
+static MemTxResult update_ite(GICv3ITSState *s, uint32_t eventid, uint64_t dte,
+                              IteEntry ite)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint64_t itt_addr;
+    MemTxResult res = MEMTX_OK;
+
+    itt_addr = (dte >> 6ULL) & ITTADDR_MASK;
+    itt_addr <<= ITTADDR_SHIFT; /* 256 byte aligned */
+
+    address_space_stq_le(as, itt_addr + (eventid * sizeof(uint64_t)),
+                         ite.itel, MEMTXATTRS_UNSPECIFIED, &res);
+
+    if (res == MEMTX_OK) {
+        address_space_stl_le(as, itt_addr + ((eventid + sizeof(uint64_t)) *
+                             sizeof(uint32_t)), ite.iteh,
+                             MEMTXATTRS_UNSPECIFIED, &res);
+    }
+   return res;
+}
+
+static bool get_ite(GICv3ITSState *s, uint32_t eventid, uint64_t dte,
+                    uint16_t *icid, uint32_t *pIntid, MemTxResult *res)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint64_t itt_addr;
+    bool status = false;
+    IteEntry ite;
+
+    itt_addr = (dte >> 6ULL) & ITTADDR_MASK;
+    itt_addr <<= ITTADDR_SHIFT; /* 256 byte aligned */
+
+    memset(&ite, 0 , sizeof(ite));
+    ite.itel = address_space_ldq_le(as, itt_addr +
+                                    (eventid * sizeof(uint64_t)),
+                                    MEMTXATTRS_UNSPECIFIED, res);
+
+    if (*res == MEMTX_OK) {
+        ite.iteh = address_space_ldl_le(as, itt_addr + ((eventid +
+                                    sizeof(uint64_t)) * sizeof(uint32_t)),
+                                    MEMTXATTRS_UNSPECIFIED, res);
+
+        if (*res == MEMTX_OK) {
+            if (ite.itel & TABLE_ENTRY_VALID_MASK) {
+                if ((ite.itel >> ITE_ENTRY_INTTYPE_SHIFT) &
+                    GITS_TYPE_PHYSICAL) {
+                    *pIntid = (ite.itel >> ITE_ENTRY_INTID_SHIFT) &
+                               ITE_ENTRY_INTID_MASK;
+                    *icid = ite.iteh & ITE_ENTRY_ICID_MASK;
+                    status = true;
+                }
+            }
+        }
+    }
+    return status;
+}
+
+static uint64_t get_dte(GICv3ITSState *s, uint32_t devid, MemTxResult *res)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint64_t l2t_addr;
+    uint64_t value;
+    bool valid_l2t;
+    uint32_t l2t_id;
+    uint32_t max_l2_entries;
+
+    if (s->dt.indirect) {
+        l2t_id = devid / (s->dt.page_sz / L1TABLE_ENTRY_SIZE);
+
+        value = address_space_ldq_le(as,
+                                     s->dt.base_addr +
+                                     (l2t_id * L1TABLE_ENTRY_SIZE),
+                                     MEMTXATTRS_UNSPECIFIED, res);
+
+        if (*res == MEMTX_OK) {
+            valid_l2t = (value & L2_TABLE_VALID_MASK) != 0;
+
+            if (valid_l2t) {
+                max_l2_entries = s->dt.page_sz / s->dt.entry_sz;
+
+                l2t_addr = value & ((1ULL << 51) - 1);
+
+                value =  address_space_ldq_le(as, l2t_addr +
+                                   ((devid % max_l2_entries) * GITS_DTE_SIZE),
+                                   MEMTXATTRS_UNSPECIFIED, res);
+            }
+        }
+    } else {
+        /* Flat level table */
+        value = address_space_ldq_le(as, s->dt.base_addr +
+                                     (devid * GITS_DTE_SIZE),
+                                     MEMTXATTRS_UNSPECIFIED, res);
+    }
+
+    return value;
+}
+
+/*
+ * This function handles the processing of following commands based on
+ * the ItsCmdType parameter passed:-
+ * 1. trigerring of lpi interrupt translation via ITS INT command
+ * 2. trigerring of lpi interrupt translation via gits_translater register
+ * 3. handling of ITS CLEAR command
+ * 4. handling of ITS DISCARD command
+ */
+static MemTxResult process_its_cmd(GICv3ITSState *s, uint64_t value,
+                                   uint32_t offset, ItsCmdType cmd)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint32_t devid, eventid;
+    MemTxResult res = MEMTX_OK;
+    bool dte_valid;
+    uint64_t dte = 0;
+    uint32_t max_eventid;
+    uint16_t icid = 0;
+    uint32_t pIntid = 0;
+    bool ite_valid = false;
+    uint64_t cte = 0;
+    bool cte_valid = false;
+    IteEntry ite;
+
+    if (cmd == NONE) {
+        devid = offset;
+    } else {
+        devid = ((value & DEVID_MASK) >> DEVID_SHIFT);
+
+        offset += NUM_BYTES_IN_DW;
+        value = address_space_ldq_le(as, s->cq.base_addr + offset,
+                                     MEMTXATTRS_UNSPECIFIED, &res);
+    }
+
+    if (res != MEMTX_OK) {
+        return res;
+    }
+
+    eventid = (value & EVENTID_MASK);
+
+    dte = get_dte(s, devid, &res);
+
+    if (res != MEMTX_OK) {
+        return res;
+    }
+    dte_valid = dte & TABLE_ENTRY_VALID_MASK;
+
+    if (dte_valid) {
+        max_eventid = (1UL << (((dte >> 1U) & SIZE_MASK) + 1));
+
+        ite_valid = get_ite(s, eventid, dte, &icid, &pIntid, &res);
+
+        if (res != MEMTX_OK) {
+            return res;
+        }
+
+        if (ite_valid) {
+            cte_valid = get_cte(s, icid, &cte, &res);
+        }
+
+        if (res != MEMTX_OK) {
+            return res;
+        }
+    }
+
+    if ((devid > s->dt.maxids.max_devids) || !dte_valid || !ite_valid ||
+            !cte_valid || (eventid > max_eventid)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: invalid command attributes "
+                      "devid %d or eventid %d or invalid dte %d or"
+                      "invalid cte %d or invalid ite %d\n",
+                      __func__, devid, eventid, dte_valid, cte_valid,
+                      ite_valid);
+        /*
+         * in this implementation, in case of error
+         * we ignore this command and move onto the next
+         * command in the queue
+         */
+    } else {
+        /*
+         * Current implementation only supports rdbase == procnum
+         * Hence rdbase physical address is ignored
+         */
+        if (cmd == DISCARD) {
+            memset(&ite, 0 , sizeof(ite));
+            /* remove mapping from interrupt translation table */
+            res = update_ite(s, eventid, dte, ite);
+        }
+    }
+
+    return res;
+}
+
+static MemTxResult process_mapti(GICv3ITSState *s, uint64_t value,
+                                 uint32_t offset, bool ignore_pInt)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint32_t devid, eventid;
+    uint32_t pIntid = 0;
+    uint32_t max_eventid, max_Intid;
+    bool dte_valid;
+    MemTxResult res = MEMTX_OK;
+    uint16_t icid = 0;
+    uint64_t dte = 0;
+    IteEntry ite;
+    uint32_t int_spurious = INTID_SPURIOUS;
+    uint64_t idbits;
+
+    devid = ((value & DEVID_MASK) >> DEVID_SHIFT);
+    offset += NUM_BYTES_IN_DW;
+    value = address_space_ldq_le(as, s->cq.base_addr + offset,
+                                 MEMTXATTRS_UNSPECIFIED, &res);
+
+    if (res != MEMTX_OK) {
+        return res;
+    }
+
+    eventid = (value & EVENTID_MASK);
+
+    if (!ignore_pInt) {
+        pIntid = ((value & pINTID_MASK) >> pINTID_SHIFT);
+    }
+
+    offset += NUM_BYTES_IN_DW;
+    value = address_space_ldq_le(as, s->cq.base_addr + offset,
+                                 MEMTXATTRS_UNSPECIFIED, &res);
+
+    if (res != MEMTX_OK) {
+        return res;
+    }
+
+    icid = value & ICID_MASK;
+
+    dte = get_dte(s, devid, &res);
+
+    if (res != MEMTX_OK) {
+        return res;
+    }
+    dte_valid = dte & TABLE_ENTRY_VALID_MASK;
+
+    max_eventid = (1UL << (((dte >> 1U) & SIZE_MASK) + 1));
+
+    if (!ignore_pInt) {
+        idbits = MIN(FIELD_EX64(s->gicv3->cpu->gicr_propbaser, GICR_PROPBASER,
+                                IDBITS), GICD_TYPER_IDBITS);
+
+        if (idbits < GICR_PROPBASER_IDBITS_THRESHOLD) {
+            return res;
+        }
+        max_Intid = (1ULL << (idbits + 1));
+    }
+
+    if ((devid > s->dt.maxids.max_devids) || (icid > s->ct.maxids.max_collids)
+            || !dte_valid || (eventid > max_eventid) ||
+            (!ignore_pInt && ((pIntid < GICV3_LPI_INTID_START) ||
+               (pIntid > max_Intid)))) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: invalid command attributes "
+                      "devid %d or icid %d or eventid %d or pIntid %d or"
+                      "unmapped dte %d\n", __func__, devid, icid, eventid,
+                      pIntid, dte_valid);
+        /*
+         * in this implementation, in case of error
+         * we ignore this command and move onto the next
+         * command in the queue
+         */
+    } else {
+        memset(&ite, 0 , sizeof(ite));
+        /* add ite entry to interrupt translation table */
+        ite.itel = (dte_valid & TABLE_ENTRY_VALID_MASK) |
+                    (GITS_TYPE_PHYSICAL << ITE_ENTRY_INTTYPE_SHIFT);
+
+        if (ignore_pInt) {
+            ite.itel |= (eventid << ITE_ENTRY_INTID_SHIFT);
+        } else {
+            ite.itel |= (pIntid << ITE_ENTRY_INTID_SHIFT);
+        }
+        ite.itel |= (int_spurious << ITE_ENTRY_INTSP_SHIFT);
+        ite.iteh |= icid;
+
+        res = update_ite(s, eventid, dte, ite);
+    }
+
+    return res;
+}
+
 static MemTxResult update_cte(GICv3ITSState *s, uint16_t icid, bool valid,
                               uint64_t rdbase)
 {
@@ -127,7 +467,8 @@ static MemTxResult process_mapc(GICv3ITSState *s, uint32_t offset)
 
     icid = value & ICID_MASK;
 
-    rdbase = (value >> R_MAPC_RDBASE_SHIFT) & RDBASE_PROCNUM_MASK;
+    rdbase = (value & R_MAPC_RDBASE_MASK) >> R_MAPC_RDBASE_SHIFT;
+    rdbase &= RDBASE_PROCNUM_MASK;
 
     valid = (value & CMD_FIELD_VALID_MASK);
 
@@ -301,8 +642,10 @@ static void process_cmdq(GICv3ITSState *s)
 
         switch (cmd) {
         case GITS_CMD_INT:
+            res = process_its_cmd(s, data, cq_offset, INT);
             break;
         case GITS_CMD_CLEAR:
+            res = process_its_cmd(s, data, cq_offset, CLEAR);
             break;
         case GITS_CMD_SYNC:
             /*
@@ -319,10 +662,13 @@ static void process_cmdq(GICv3ITSState *s)
             res = process_mapc(s, cq_offset);
             break;
         case GITS_CMD_MAPTI:
+            res = process_mapti(s, data, cq_offset, false);
             break;
         case GITS_CMD_MAPI:
+            res = process_mapti(s, data, cq_offset, true);
             break;
         case GITS_CMD_DISCARD:
+            res = process_its_cmd(s, data, cq_offset, DISCARD);
             break;
         case GITS_CMD_INV:
         case GITS_CMD_INVALL:
@@ -484,7 +830,20 @@ static MemTxResult gicv3_its_translation_write(void *opaque, hwaddr offset,
                                                uint64_t data, unsigned size,
                                                MemTxAttrs attrs)
 {
+    GICv3ITSState *s = (GICv3ITSState *)opaque;
     MemTxResult result = MEMTX_OK;
+    uint32_t devid = 0;
+
+    switch (offset) {
+    case GITS_TRANSLATER:
+        if (s->ctlr & ITS_CTLR_ENABLED) {
+            devid = attrs.requester_id;
+            result = process_its_cmd(s, data, devid, NONE);
+        }
+        break;
+    default:
+        break;
+    }
 
     return result;
 }
diff --git a/hw/intc/gicv3_internal.h b/hw/intc/gicv3_internal.h
index a27b1e4d19..f7675a5adc 100644
--- a/hw/intc/gicv3_internal.h
+++ b/hw/intc/gicv3_internal.h
@@ -123,6 +123,20 @@
 #define GICR_TYPER_COMMONLPIAFF      (0x3 << 24)
 #define GICR_TYPER_AFFINITYVALUE     (0xFFFFFFFFULL << 32)
 
+FIELD(GICR_PROPBASER, IDBITS, 0, 5)
+FIELD(GICR_PROPBASER, INNERCACHE, 7, 3)
+FIELD(GICR_PROPBASER, SHAREABILITY, 10, 2)
+FIELD(GICR_PROPBASER, PHYADDR, 12, 40)
+FIELD(GICR_PROPBASER, OUTERCACHE, 56, 3)
+
+#define GICR_PROPBASER_IDBITS_THRESHOLD          0xd
+
+FIELD(GICR_PENDBASER, INNERCACHE, 7, 3)
+FIELD(GICR_PENDBASER, SHAREABILITY, 10, 2)
+FIELD(GICR_PENDBASER, PHYADDR, 16, 36)
+FIELD(GICR_PENDBASER, OUTERCACHE, 56, 3)
+FIELD(GICR_PENDBASER, PTZ, 62, 1)
+
 #define GICR_WAKER_ProcessorSleep    (1U << 1)
 #define GICR_WAKER_ChildrenAsleep    (1U << 2)
 
@@ -322,6 +336,13 @@ FIELD(MAPC, RDBASE, 16, 32)
 #define ITTADDR_MASK              ((1ULL << ITTADDR_LENGTH) - 1)
 #define SIZE_MASK                 0x1f
 
+/* MAPI command fields */
+#define EVENTID_MASK              ((1ULL << 32) - 1)
+
+/* MAPTI command fields */
+#define pINTID_SHIFT                 32
+#define pINTID_MASK               MAKE_64BIT_MASK(32, 32)
+
 #define DEVID_SHIFT                  32
 #define DEVID_MASK                MAKE_64BIT_MASK(32, 32)
 
@@ -347,6 +368,11 @@ FIELD(MAPC, RDBASE, 16, 32)
  * vPEID = 16 bits
  */
 #define ITS_ITT_ENTRY_SIZE            0xC
+#define ITE_ENTRY_INTTYPE_SHIFT        1
+#define ITE_ENTRY_INTID_SHIFT          2
+#define ITE_ENTRY_INTID_MASK         ((1ULL << 24) - 1)
+#define ITE_ENTRY_INTSP_SHIFT          26
+#define ITE_ENTRY_ICID_MASK          ((1ULL << 16) - 1)
 
 /* 16 bits EventId */
 #define ITS_IDBITS                   GICD_TYPER_IDBITS
diff --git a/include/hw/intc/arm_gicv3_common.h b/include/hw/intc/arm_gicv3_common.h
index 1fd5cedbbd..0715b0bc2a 100644
--- a/include/hw/intc/arm_gicv3_common.h
+++ b/include/hw/intc/arm_gicv3_common.h
@@ -36,6 +36,8 @@
 #define GICV3_MAXIRQ 1020
 #define GICV3_MAXSPI (GICV3_MAXIRQ - GIC_INTERNAL)
 
+#define GICV3_LPI_INTID_START 8192
+
 #define GICV3_REDIST_SIZE 0x20000
 
 /* Number of SGI target-list bits */
-- 
2.27.0



  parent reply	other threads:[~2021-06-30 15:38 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-30 15:31 [PATCH v5 00/10] GICv3 LPI and ITS feature implementation Shashi Mallela
2021-06-30 15:31 ` [PATCH v5 01/10] hw/intc: GICv3 ITS initial framework Shashi Mallela
2021-07-05 14:58   ` Peter Maydell
2021-07-05 15:55     ` shashi.mallela
2021-07-05 16:25       ` Peter Maydell
2021-07-05 17:04         ` shashi.mallela
2021-07-05 18:58           ` Peter Maydell
2021-07-07  2:08             ` shashi.mallela
2021-07-06  7:44   ` Eric Auger
2021-07-07  2:06     ` shashi.mallela
2021-06-30 15:31 ` [PATCH v5 02/10] hw/intc: GICv3 ITS register definitions added Shashi Mallela
2021-07-06  9:29   ` Eric Auger
2021-07-08 17:27     ` Eric Auger
2021-08-05 21:14       ` shashi.mallela
2021-06-30 15:31 ` [PATCH v5 03/10] hw/intc: GICv3 ITS command queue framework Shashi Mallela
2021-07-06  9:31   ` Eric Auger
2021-06-30 15:31 ` Shashi Mallela [this message]
2021-07-05 14:07   ` [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing Peter Maydell
2021-07-06  9:27     ` Eric Auger
2021-07-07  2:02       ` shashi.mallela
2021-07-05 14:54   ` Peter Maydell
2021-07-06  0:47     ` shashi.mallela
2021-07-06  3:25       ` shashi.mallela
2021-07-06  9:19         ` Peter Maydell
2021-07-06 12:46           ` shashi.mallela
2021-07-06 13:27             ` Peter Maydell
2021-07-07  2:08               ` shashi.mallela
2021-07-06 10:04         ` Eric Auger
2021-07-06 10:07           ` Peter Maydell
2021-07-06 10:05   ` Eric Auger
2021-06-30 15:31 ` [PATCH v5 05/10] hw/intc: GICv3 ITS Feature enablement Shashi Mallela
2021-07-05 14:20   ` Peter Maydell
2021-06-30 15:31 ` [PATCH v5 06/10] hw/intc: GICv3 redistributor ITS processing Shashi Mallela
2021-07-05 14:43   ` Peter Maydell
2021-06-30 15:31 ` [PATCH v5 07/10] hw/arm/sbsa-ref: add ITS support in SBSA GIC Shashi Mallela
2021-07-05 14:59   ` Peter Maydell
2021-06-30 15:31 ` [PATCH v5 08/10] tests/data/acpi/virt: Add IORT files for ITS Shashi Mallela
2021-06-30 15:31 ` [PATCH v5 09/10] hw/arm/virt: add ITS support in virt GIC Shashi Mallela
2021-06-30 15:31 ` [PATCH v5 10/10] tests/data/acpi/virt: Update IORT files for ITS Shashi Mallela
2021-07-05 15:02   ` Peter Maydell
2021-07-05 15:05 ` [PATCH v5 00/10] GICv3 LPI and ITS feature implementation Peter Maydell

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all data and code used by this external index.