From d011e4e654d7f519bf892995b9f4b453dbf8a3e5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 20 Dec 2016 09:44:41 +0000 Subject: [PATCH] irqchip/gic-v3-its: Add VLPI map/unmap operations In order to let a VLPI being injected into a guest, the VLPI must be mapped using the VMAPTI command. When moved to a different vcpu, it must be moved with the VMOVI command. These commands are issued via the irq_set_vcpu_affinity method, making sure we unmap the corresponding host LPI first. The reverse is also done when the VLPI is unmapped from the guest. Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its.c | 250 ++++++++++++++++++++++++++++++- 1 file changed, 247 insertions(+), 3 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index ead06d443c3b..5187c4b116d4 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -115,11 +115,17 @@ struct event_lpi_map { u16 *col_map; irq_hw_number_t lpi_base; int nr_lpis; + struct mutex vlpi_lock; + struct its_vm *vm; + struct its_vlpi_map *vlpi_maps; + int nr_vlpis; }; /* - * The ITS view of a device - belongs to an ITS, a collection, owns an - * interrupt translation table, and a list of interrupts. + * The ITS view of a device - belongs to an ITS, owns an interrupt + * translation table, and a list of interrupts. If it some of its + * LPIs are injected into a guest (GICv4), the event_map.vm field + * indicates which one. */ struct its_device { struct list_head entry; @@ -205,6 +211,21 @@ struct its_cmd_desc { struct { struct its_collection *col; } its_invall_cmd; + + struct { + struct its_vpe *vpe; + struct its_device *dev; + u32 virt_id; + u32 event_id; + bool db_enabled; + } its_vmapti_cmd; + + struct { + struct its_vpe *vpe; + struct its_device *dev; + u32 event_id; + bool db_enabled; + } its_vmovi_cmd; }; }; @@ -221,6 +242,9 @@ struct its_cmd_block { typedef struct its_collection *(*its_cmd_builder_t)(struct its_cmd_block *, struct its_cmd_desc *); +typedef struct its_vpe *(*its_cmd_vbuilder_t)(struct its_cmd_block *, + struct its_cmd_desc *); + static void its_mask_encode(u64 *raw_cmd, u64 val, int h, int l) { u64 mask = GENMASK_ULL(h, l); @@ -273,6 +297,26 @@ static void its_encode_collection(struct its_cmd_block *cmd, u16 col) its_mask_encode(&cmd->raw_cmd[2], col, 15, 0); } +static void its_encode_vpeid(struct its_cmd_block *cmd, u16 vpeid) +{ + its_mask_encode(&cmd->raw_cmd[1], vpeid, 47, 32); +} + +static void its_encode_virt_id(struct its_cmd_block *cmd, u32 virt_id) +{ + its_mask_encode(&cmd->raw_cmd[2], virt_id, 31, 0); +} + +static void its_encode_db_phys_id(struct its_cmd_block *cmd, u32 db_phys_id) +{ + its_mask_encode(&cmd->raw_cmd[2], db_phys_id, 63, 32); +} + +static void its_encode_db_valid(struct its_cmd_block *cmd, bool db_valid) +{ + its_mask_encode(&cmd->raw_cmd[2], db_valid, 0, 0); +} + static inline void its_fixup_cmd(struct its_cmd_block *cmd) { /* Let's fixup BE commands */ @@ -431,6 +475,50 @@ static struct its_collection *its_build_invall_cmd(struct its_cmd_block *cmd, return NULL; } +static struct its_vpe *its_build_vmapti_cmd(struct its_cmd_block *cmd, + struct its_cmd_desc *desc) +{ + u32 db; + + if (desc->its_vmapti_cmd.db_enabled) + db = desc->its_vmapti_cmd.vpe->vpe_db_lpi; + else + db = 1023; + + its_encode_cmd(cmd, GITS_CMD_VMAPTI); + its_encode_devid(cmd, desc->its_vmapti_cmd.dev->device_id); + its_encode_vpeid(cmd, desc->its_vmapti_cmd.vpe->vpe_id); + its_encode_event_id(cmd, desc->its_vmapti_cmd.event_id); + its_encode_db_phys_id(cmd, db); + its_encode_virt_id(cmd, desc->its_vmapti_cmd.virt_id); + + its_fixup_cmd(cmd); + + return desc->its_vmapti_cmd.vpe; +} + +static struct its_vpe *its_build_vmovi_cmd(struct its_cmd_block *cmd, + struct its_cmd_desc *desc) +{ + u32 db; + + if (desc->its_vmovi_cmd.db_enabled) + db = desc->its_vmovi_cmd.vpe->vpe_db_lpi; + else + db = 1023; + + its_encode_cmd(cmd, GITS_CMD_VMOVI); + its_encode_devid(cmd, desc->its_vmovi_cmd.dev->device_id); + its_encode_vpeid(cmd, desc->its_vmovi_cmd.vpe->vpe_id); + its_encode_event_id(cmd, desc->its_vmovi_cmd.event_id); + its_encode_db_phys_id(cmd, db); + its_encode_db_valid(cmd, true); + + its_fixup_cmd(cmd); + + return desc->its_vmovi_cmd.vpe; +} + static u64 its_cmd_ptr_to_offset(struct its_node *its, struct its_cmd_block *ptr) { @@ -582,6 +670,18 @@ static void its_build_sync_cmd(struct its_cmd_block *sync_cmd, static BUILD_SINGLE_CMD_FUNC(its_send_single_command, its_cmd_builder_t, struct its_collection, its_build_sync_cmd) +static void its_build_vsync_cmd(struct its_cmd_block *sync_cmd, + struct its_vpe *sync_vpe) +{ + its_encode_cmd(sync_cmd, GITS_CMD_VSYNC); + its_encode_vpeid(sync_cmd, sync_vpe->vpe_id); + + its_fixup_cmd(sync_cmd); +} + +static BUILD_SINGLE_CMD_FUNC(its_send_single_vcommand, its_cmd_vbuilder_t, + struct its_vpe, its_build_vsync_cmd) + static void its_send_int(struct its_device *dev, u32 event_id) { struct its_cmd_desc desc; @@ -675,6 +775,33 @@ static void its_send_invall(struct its_node *its, struct its_collection *col) its_send_single_command(its, its_build_invall_cmd, &desc); } +static void its_send_vmapti(struct its_device *dev, u32 id) +{ + struct its_vlpi_map *map = &dev->event_map.vlpi_maps[id]; + struct its_cmd_desc desc; + + desc.its_vmapti_cmd.vpe = map->vpe; + desc.its_vmapti_cmd.dev = dev; + desc.its_vmapti_cmd.virt_id = map->vintid; + desc.its_vmapti_cmd.event_id = id; + desc.its_vmapti_cmd.db_enabled = map->db_enabled; + + its_send_single_vcommand(dev->its, its_build_vmapti_cmd, &desc); +} + +static void its_send_vmovi(struct its_device *dev, u32 id) +{ + struct its_vlpi_map *map = &dev->event_map.vlpi_maps[id]; + struct its_cmd_desc desc; + + desc.its_vmovi_cmd.vpe = map->vpe; + desc.its_vmovi_cmd.dev = dev; + desc.its_vmovi_cmd.event_id = id; + desc.its_vmovi_cmd.db_enabled = map->db_enabled; + + its_send_single_vcommand(dev->its, its_build_vmovi_cmd, &desc); +} + /* * irqchip functions - assumes MSI, mostly. */ @@ -787,19 +914,135 @@ static int its_irq_set_irqchip_state(struct irq_data *d, return 0; } +static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + u32 event = its_get_event_id(d); + int ret = 0; + + if (!info->map) + return -EINVAL; + + mutex_lock(&its_dev->event_map.vlpi_lock); + + if (!its_dev->event_map.vm) { + struct its_vlpi_map *maps; + + maps = kzalloc(sizeof(*maps) * its_dev->event_map.nr_lpis, + GFP_KERNEL); + if (!maps) { + ret = -ENOMEM; + goto out; + } + + its_dev->event_map.vm = info->map->vm; + its_dev->event_map.vlpi_maps = maps; + } else if (its_dev->event_map.vm != info->map->vm) { + ret = -EINVAL; + goto out; + } + + /* Get our private copy of the mapping information */ + its_dev->event_map.vlpi_maps[event] = *info->map; + + if (irqd_is_forwarded_to_vcpu(d)) { + /* Already mapped, move it around */ + its_send_vmovi(its_dev, event); + } else { + /* Drop the physical mapping */ + its_send_discard(its_dev, event); + + /* and install the virtual one */ + its_send_vmapti(its_dev, event); + irqd_set_forwarded_to_vcpu(d); + + /* Increment the number of VLPIs */ + its_dev->event_map.nr_vlpis++; + } + +out: + mutex_unlock(&its_dev->event_map.vlpi_lock); + return ret; +} + +static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + u32 event = its_get_event_id(d); + int ret = 0; + + mutex_lock(&its_dev->event_map.vlpi_lock); + + if (!its_dev->event_map.vm || + !its_dev->event_map.vlpi_maps[event].vm) { + ret = -EINVAL; + goto out; + } + + /* Copy our mapping information to the incoming request */ + *info->map = its_dev->event_map.vlpi_maps[event]; + +out: + mutex_unlock(&its_dev->event_map.vlpi_lock); + return ret; +} + +static int its_vlpi_unmap(struct irq_data *d) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + u32 event = its_get_event_id(d); + int ret = 0; + + mutex_lock(&its_dev->event_map.vlpi_lock); + + if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d)) { + ret = -EINVAL; + goto out; + } + + /* Drop the virtual mapping */ + its_send_discard(its_dev, event); + + /* and restore the physical one */ + irqd_clr_forwarded_to_vcpu(d); + its_send_mapti(its_dev, d->hwirq, event); + lpi_update_config(d, 0xff, (LPI_PROP_DEFAULT_PRIO | + LPI_PROP_ENABLED | + LPI_PROP_GROUP1)); + + /* + * Drop the refcount and make the device available again if + * this was the last VLPI. + */ + if (!--its_dev->event_map.nr_vlpis) { + its_dev->event_map.vm = NULL; + kfree(its_dev->event_map.vlpi_maps); + } + +out: + mutex_unlock(&its_dev->event_map.vlpi_lock); + return ret; +} + static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info) { struct its_device *its_dev = irq_data_get_irq_chip_data(d); struct its_cmd_info *info = vcpu_info; /* Need a v4 ITS */ - if (!its_dev->its->is_v4 || !info) + if (!its_dev->its->is_v4) return -EINVAL; + /* Unmap request? */ + if (!info) + return its_vlpi_unmap(d); + switch (info->cmd_type) { case MAP_VLPI: + return its_vlpi_map(d, info); case GET_VLPI: + return its_vlpi_get(d, info); case PROP_UPDATE_VLPI: case PROP_UPDATE_AND_INV_VLPI: @@ -1518,6 +1761,7 @@ static struct its_device *its_create_device(struct its_node *its, u32 dev_id, dev->event_map.col_map = col_map; dev->event_map.lpi_base = lpi_base; dev->event_map.nr_lpis = nr_lpis; + mutex_init(&dev->event_map.vlpi_lock); dev->device_id = dev_id; INIT_LIST_HEAD(&dev->entry); -- 2.20.1