When launching a virtual machine, Gunyah userspace allocates memory for the guest and informs Gunyah about these memory regions through SET_USER_MEMORY_REGION ioctl. Co-developed-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx> Signed-off-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx> Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx> --- drivers/virt/gunyah/Makefile | 2 +- drivers/virt/gunyah/vm_mgr.c | 46 +++++++ drivers/virt/gunyah/vm_mgr.h | 28 +++- drivers/virt/gunyah/vm_mgr_mm.c | 223 ++++++++++++++++++++++++++++++++ include/uapi/linux/gunyah.h | 22 ++++ 5 files changed, 319 insertions(+), 2 deletions(-) create mode 100644 drivers/virt/gunyah/vm_mgr_mm.c diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile index 03951cf82023..ff8bc4925392 100644 --- a/drivers/virt/gunyah/Makefile +++ b/drivers/virt/gunyah/Makefile @@ -2,5 +2,5 @@ obj-$(CONFIG_GUNYAH) += gunyah.o -gunyah_rsc_mgr-y += rsc_mgr.o rsc_mgr_rpc.o vm_mgr.o +gunyah_rsc_mgr-y += rsc_mgr.o rsc_mgr_rpc.o vm_mgr.o vm_mgr_mm.o obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o diff --git a/drivers/virt/gunyah/vm_mgr.c b/drivers/virt/gunyah/vm_mgr.c index 0864dbd77e28..b847fde63333 100644 --- a/drivers/virt/gunyah/vm_mgr.c +++ b/drivers/virt/gunyah/vm_mgr.c @@ -35,14 +35,55 @@ static __must_check struct gunyah_vm *gunyah_vm_alloc(struct gh_rm_rpc *rm) ghvm->vmid = vmid; ghvm->rm = rm; + mutex_init(&ghvm->mm_lock); + INIT_LIST_HEAD(&ghvm->memory_mappings); + return ghvm; } static long gh_vm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { + struct gunyah_vm *ghvm = filp->private_data; + void __user *argp = (void __user *)arg; long r; switch (cmd) { + case GH_VM_SET_USER_MEM_REGION: { + struct gunyah_vm_memory_mapping *mapping; + struct gh_userspace_memory_region region; + + r = -EFAULT; + if (copy_from_user(®ion, argp, sizeof(region))) + break; + + r = -EINVAL; + /* All other flag bits are reserved for future use */ + if (region.flags & ~(GH_MEM_ALLOW_READ | GH_MEM_ALLOW_WRITE | GH_MEM_ALLOW_EXEC | + GH_MEM_LENT)) + break; + + + if (region.memory_size) { + r = 0; + mapping = gh_vm_mem_mapping_alloc(ghvm, ®ion); + if (IS_ERR(mapping)) { + r = PTR_ERR(mapping); + break; + } + } else { + mapping = gh_vm_mem_mapping_find(ghvm, region.label); + if (IS_ERR(mapping)) { + r = PTR_ERR(mapping); + break; + } + r = 0; + if (!mapping) + break; + gh_vm_mem_mapping_reclaim(ghvm, mapping); + kfree(mapping); + } + break; + } default: r = -ENOTTY; break; @@ -54,7 +95,12 @@ static long gh_vm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) static int gh_vm_release(struct inode *inode, struct file *filp) { struct gunyah_vm *ghvm = filp->private_data; + struct gunyah_vm_memory_mapping *mapping, *tmp; + list_for_each_entry_safe(mapping, tmp, &ghvm->memory_mappings, list) { + gh_vm_mem_mapping_reclaim(ghvm, mapping); + kfree(mapping); + } put_gh_rm(ghvm->rm); kfree(ghvm); return 0; diff --git a/drivers/virt/gunyah/vm_mgr.h b/drivers/virt/gunyah/vm_mgr.h index e47f34de7f9e..6b38bf780f76 100644 --- a/drivers/virt/gunyah/vm_mgr.h +++ b/drivers/virt/gunyah/vm_mgr.h @@ -7,14 +7,40 @@ #define _GH_PRIV_VM_MGR_H #include <linux/gunyah_rsc_mgr.h> +#include <linux/list.h> +#include <linux/miscdevice.h> +#include <linux/mutex.h> #include <uapi/linux/gunyah.h> long gh_dev_vm_mgr_ioctl(struct gh_rm *rm, unsigned int cmd, unsigned long arg); +enum gunyah_vm_mem_share_type { + VM_MEM_SHARE, + VM_MEM_LEND, +}; + +struct gunyah_vm_memory_mapping { + struct list_head list; + enum gunyah_vm_mem_share_type share_type; + struct gh_rm_mem_parcel parcel; + + __u64 guest_phys_addr; + struct page **pages; + unsigned long npages; +}; + struct gunyah_vm { u16 vmid; - struct gh_rm_rpc *rm; + struct gh_rm *rm; + + struct mutex mm_lock; + struct list_head memory_mappings; }; +struct gunyah_vm_memory_mapping *gh_vm_mem_mapping_alloc(struct gunyah_vm *ghvm, + struct gh_userspace_memory_region *region); +void gh_vm_mem_mapping_reclaim(struct gunyah_vm *ghvm, struct gunyah_vm_memory_mapping *mapping); +struct gunyah_vm_memory_mapping *gh_vm_mem_mapping_find(struct gunyah_vm *ghvm, u32 label); + #endif diff --git a/drivers/virt/gunyah/vm_mgr_mm.c b/drivers/virt/gunyah/vm_mgr_mm.c new file mode 100644 index 000000000000..f2dbdb4ee8ab --- /dev/null +++ b/drivers/virt/gunyah/vm_mgr_mm.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#define pr_fmt(fmt) "gh_vm_mgr: " fmt + +#include <linux/gunyah_rsc_mgr.h> +#include <linux/mm.h> + +#include <uapi/linux/gunyah.h> + +#include "vm_mgr.h" + +static inline bool page_contiguous(phys_addr_t p, phys_addr_t t) +{ + return t - p == PAGE_SIZE; +} + +static struct gunyah_vm_memory_mapping *__gh_vm_mem_mapping_find(struct gunyah_vm *ghvm, u32 label) +{ + struct gunyah_vm_memory_mapping *mapping; + + + list_for_each_entry(mapping, &ghvm->memory_mappings, list) + if (mapping->parcel.label == label) + return mapping; + + return NULL; +} + +void gh_vm_mem_mapping_reclaim(struct gunyah_vm *ghvm, struct gunyah_vm_memory_mapping *mapping) +{ + int i, ret = 0; + + if (mapping->parcel.mem_handle != GH_MEM_HANDLE_INVAL) { + ret = gh_rm_mem_reclaim(ghvm->rm, &mapping->parcel); + if (ret) + pr_warn("Failed to reclaim memory parcel for label %d: %d\n", + mapping->parcel.label, ret); + } + + if (!ret) + for (i = 0; i < mapping->npages; i++) + unpin_user_page(mapping->pages[i]); + + kfree(mapping->pages); + kfree(mapping->parcel.acl_entries); + kfree(mapping->parcel.mem_entries); + + mutex_lock(&ghvm->mm_lock); + list_del(&mapping->list); + mutex_unlock(&ghvm->mm_lock); +} + +struct gunyah_vm_memory_mapping *gh_vm_mem_mapping_find(struct gunyah_vm *ghvm, u32 label) +{ + struct gunyah_vm_memory_mapping *mapping; + int ret; + + ret = mutex_lock_interruptible(&ghvm->mm_lock); + if (ret) + return ERR_PTR(ret); + mapping = __gh_vm_mem_mapping_find(ghvm, label); + mutex_unlock(&ghvm->mm_lock); + return mapping ? : ERR_PTR(-ENODEV); +} + +struct gunyah_vm_memory_mapping *gh_vm_mem_mapping_alloc(struct gunyah_vm *ghvm, + struct gh_userspace_memory_region *region) +{ + phys_addr_t curr_page, prev_page; + struct gunyah_vm_memory_mapping *mapping, *tmp_mapping; + struct gh_rm_mem_entry *mem_entries; + int i, j, pinned, ret = 0; + struct gh_rm_mem_parcel *parcel; + size_t entry_size; + u16 vmid; + + if (!region->memory_size || !PAGE_ALIGNED(region->memory_size) || + !PAGE_ALIGNED(region->userspace_addr)) + return ERR_PTR(-EINVAL); + + if (!gh_api_has_feature(GH_API_FEATURE_MEMEXTENT)) + return ERR_PTR(-EOPNOTSUPP); + + ret = mutex_lock_interruptible(&ghvm->mm_lock); + if (ret) + return ERR_PTR(ret); + mapping = __gh_vm_mem_mapping_find(ghvm, region->label); + if (mapping) { + mutex_unlock(&ghvm->mm_lock); + return ERR_PTR(-EEXIST); + } + + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); + if (!mapping) { + ret = -ENOMEM; + goto unlock; + } + + mapping->parcel.label = region->label; + mapping->guest_phys_addr = region->guest_phys_addr; + mapping->npages = region->memory_size >> PAGE_SHIFT; + parcel = &mapping->parcel; + parcel->mem_handle = GH_MEM_HANDLE_INVAL; /* to be filled later by mem_share/mem_lend */ + parcel->mem_type = GH_RM_MEM_TYPE_NORMAL; + + /* Check for overlap */ + list_for_each_entry(tmp_mapping, &ghvm->memory_mappings, list) { + if (!((mapping->guest_phys_addr + (mapping->npages << PAGE_SHIFT) <= + tmp_mapping->guest_phys_addr) || + (mapping->guest_phys_addr >= + tmp_mapping->guest_phys_addr + (tmp_mapping->npages << PAGE_SHIFT)))) { + ret = -EEXIST; + goto unlock; + } + } + + list_add(&mapping->list, &ghvm->memory_mappings); +unlock: + mutex_unlock(&ghvm->mm_lock); + if (ret) + goto free_mapping; + + mapping->pages = kcalloc(mapping->npages, sizeof(*mapping->pages), GFP_KERNEL); + if (!mapping->pages) { + ret = -ENOMEM; + goto reclaim; + } + + pinned = pin_user_pages_fast(region->userspace_addr, mapping->npages, + FOLL_WRITE | FOLL_LONGTERM, mapping->pages); + if (pinned < 0) { + ret = pinned; + goto reclaim; + } else if (pinned != mapping->npages) { + ret = -EFAULT; + mapping->npages = pinned; /* update npages for reclaim */ + goto reclaim; + } + + if (region->flags & GH_MEM_LENT) { + parcel->n_acl_entries = 1; + mapping->share_type = VM_MEM_LEND; + } else { + parcel->n_acl_entries = 2; + mapping->share_type = VM_MEM_SHARE; + } + parcel->acl_entries = kcalloc(parcel->n_acl_entries, + sizeof(*parcel->acl_entries), + GFP_KERNEL); + if (!parcel->acl_entries) { + ret = -ENOMEM; + goto reclaim; + } + + parcel->acl_entries[0].vmid = cpu_to_le16(ghvm->vmid); + if (region->flags & GH_MEM_ALLOW_READ) + parcel->acl_entries[0].perms |= GH_RM_ACL_R; + if (region->flags & GH_MEM_ALLOW_WRITE) + parcel->acl_entries[0].perms |= GH_RM_ACL_W; + if (region->flags & GH_MEM_ALLOW_EXEC) + parcel->acl_entries[0].perms |= GH_RM_ACL_X; + + if (mapping->share_type == VM_MEM_SHARE) { + ret = gh_rm_get_vmid(ghvm->rm, &vmid); + if (ret) { + if (ret > 0) { + pr_warn("RM failed to get this VM's VMID: %d", ret); + ret = -EINVAL; + } + goto reclaim; + } + + parcel->acl_entries[1].vmid = cpu_to_le16(vmid); + /* Host assumed to have all these permissions. Gunyah will not + * grant new permissions if host actually had less than RWX + */ + parcel->acl_entries[1].perms |= GH_RM_ACL_R | GH_RM_ACL_W | GH_RM_ACL_X; + } + + mem_entries = kcalloc(mapping->npages, sizeof(*mem_entries), GFP_KERNEL); + if (!mem_entries) { + ret = -ENOMEM; + goto reclaim; + } + + /* reduce number of entries by combining contiguous pages into single memory entry */ + prev_page = page_to_phys(mapping->pages[0]); + mem_entries[0].ipa_base = cpu_to_le64(prev_page); + entry_size = PAGE_SIZE; + for (i = 1, j = 0; i < mapping->npages; i++) { + curr_page = page_to_phys(mapping->pages[i]); + if (page_contiguous(prev_page, curr_page)) { + entry_size += PAGE_SIZE; + } else { + mem_entries[j].size = cpu_to_le64(entry_size); + j++; + mem_entries[j].ipa_base = cpu_to_le64(curr_page); + entry_size = PAGE_SIZE; + } + + prev_page = curr_page; + } + mem_entries[j].size = cpu_to_le64(entry_size); + + parcel->n_mem_entries = j + 1; + parcel->mem_entries = kmemdup(mem_entries, sizeof(*mem_entries) * parcel->n_mem_entries, + GFP_KERNEL); + kfree(mem_entries); + if (!parcel->mem_entries) { + ret = -ENOMEM; + goto reclaim; + } + + return mapping; +reclaim: + gh_vm_mem_mapping_reclaim(ghvm, mapping); +free_mapping: + kfree(mapping); + return ERR_PTR(ret); +} diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h index 88a40d6e0b96..574f33b198d0 100644 --- a/include/uapi/linux/gunyah.h +++ b/include/uapi/linux/gunyah.h @@ -20,4 +20,26 @@ */ #define GH_CREATE_VM _IO(GH_IOCTL_TYPE, 0x0) /* Returns a Gunyah VM fd */ +/* + * ioctls for VM fds + */ +struct gh_userspace_memory_region { + __u32 label; +#define GH_MEM_ALLOW_READ (1UL << 0) +#define GH_MEM_ALLOW_WRITE (1UL << 1) +#define GH_MEM_ALLOW_EXEC (1UL << 2) +/* + * The guest will be lent the memory instead of shared. + * In other words, the guest has exclusive access to the memory region and the host loses access. + */ +#define GH_MEM_LENT (1UL << 3) + __u32 flags; + __u64 guest_phys_addr; + __u64 memory_size; + __u64 userspace_addr; +}; + +#define GH_VM_SET_USER_MEM_REGION _IOW(GH_IOCTL_TYPE, 0x1, \ + struct gh_userspace_memory_region) + #endif -- 2.39.0