diff options
Diffstat (limited to 'drivers/staging')
| -rw-r--r-- | drivers/staging/android/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/staging/android/Makefile | 1 | ||||
| -rw-r--r-- | drivers/staging/android/TODO | 9 | ||||
| -rw-r--r-- | drivers/staging/android/uapi/vsoc_shm.h | 295 | ||||
| -rw-r--r-- | drivers/staging/android/vsoc.c | 1149 |
5 files changed, 0 insertions, 1462 deletions
diff --git a/drivers/staging/android/Kconfig b/drivers/staging/android/Kconfig index d6d605d5cbde..8d8fd5c29349 100644 --- a/drivers/staging/android/Kconfig +++ b/drivers/staging/android/Kconfig @@ -14,14 +14,6 @@ config ASHMEM It is, in theory, a good memory allocator for low-memory devices, because it can discard shared memory units when under memory pressure. -config ANDROID_VSOC - tristate "Android Virtual SoC support" - depends on PCI_MSI - help - This option adds support for the Virtual SoC driver needed to boot - a 'cuttlefish' Android image inside QEmu. The driver interacts with - a QEmu ivshmem device. If built as a module, it will be called vsoc. - source "drivers/staging/android/ion/Kconfig" endif # if ANDROID diff --git a/drivers/staging/android/Makefile b/drivers/staging/android/Makefile index 14bd9c6ce10d..3b66cd0b0ec5 100644 --- a/drivers/staging/android/Makefile +++ b/drivers/staging/android/Makefile @@ -4,4 +4,3 @@ ccflags-y += -I$(src) # needed for trace events obj-y += ion/ obj-$(CONFIG_ASHMEM) += ashmem.o -obj-$(CONFIG_ANDROID_VSOC) += vsoc.o diff --git a/drivers/staging/android/TODO b/drivers/staging/android/TODO index 767dd98fd92d..80eccfaf6db5 100644 --- a/drivers/staging/android/TODO +++ b/drivers/staging/android/TODO @@ -9,14 +9,5 @@ ion/ - Split /dev/ion up into multiple nodes (e.g. /dev/ion/heap0) - Better test framework (integration with VGEM was suggested) -vsoc.c, uapi/vsoc_shm.h - - The current driver uses the same wait queue for all of the futexes in a - region. This will cause false wakeups in regions with a large number of - waiting threads. We should eventually use multiple queues and select the - queue based on the region. - - Add debugfs support for examining the permissions of regions. - - Remove VSOC_WAIT_FOR_INCOMING_INTERRUPT ioctl. This functionality has been - superseded by the futex and is there for legacy reasons. - Please send patches to Greg Kroah-Hartman <greg@kroah.com> and Cc: Arve Hjønnevåg <arve@android.com> and Riley Andrews <riandrews@android.com> diff --git a/drivers/staging/android/uapi/vsoc_shm.h b/drivers/staging/android/uapi/vsoc_shm.h deleted file mode 100644 index 6291fb24efb2..000000000000 --- a/drivers/staging/android/uapi/vsoc_shm.h +++ /dev/null @@ -1,295 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Copyright (C) 2017 Google, Inc. - * - */ - -#ifndef _UAPI_LINUX_VSOC_SHM_H -#define _UAPI_LINUX_VSOC_SHM_H - -#include <linux/types.h> - -/** - * A permission is a token that permits a receiver to read and/or write an area - * of memory within a Vsoc region. - * - * An fd_scoped permission grants both read and write access, and can be - * attached to a file description (see open(2)). - * Ownership of the area can then be shared by passing a file descriptor - * among processes. - * - * begin_offset and end_offset define the area of memory that is controlled by - * the permission. owner_offset points to a word, also in shared memory, that - * controls ownership of the area. - * - * ownership of the region expires when the associated file description is - * released. - * - * At most one permission can be attached to each file description. - * - * This is useful when implementing HALs like gralloc that scope and pass - * ownership of shared resources via file descriptors. - * - * The caller is responsibe for doing any fencing. - * - * The calling process will normally identify a currently free area of - * memory. It will construct a proposed fd_scoped_permission_arg structure: - * - * begin_offset and end_offset describe the area being claimed - * - * owner_offset points to the location in shared memory that indicates the - * owner of the area. - * - * owned_value is the value that will be stored in owner_offset iff the - * permission can be granted. It must be different than VSOC_REGION_FREE. - * - * Two fd_scoped_permission structures are compatible if they vary only by - * their owned_value fields. - * - * The driver ensures that, for any group of simultaneous callers proposing - * compatible fd_scoped_permissions, it will accept exactly one of the - * propopsals. The other callers will get a failure with errno of EAGAIN. - * - * A process receiving a file descriptor can identify the region being - * granted using the VSOC_GET_FD_SCOPED_PERMISSION ioctl. - */ -struct fd_scoped_permission { - __u32 begin_offset; - __u32 end_offset; - __u32 owner_offset; - __u32 owned_value; -}; - -/* - * This value represents a free area of memory. The driver expects to see this - * value at owner_offset when creating a permission otherwise it will not do it, - * and will write this value back once the permission is no longer needed. - */ -#define VSOC_REGION_FREE ((__u32)0) - -/** - * ioctl argument for VSOC_CREATE_FD_SCOPE_PERMISSION - */ -struct fd_scoped_permission_arg { - struct fd_scoped_permission perm; - __s32 managed_region_fd; -}; - -#define VSOC_NODE_FREE ((__u32)0) - -/* - * Describes a signal table in shared memory. Each non-zero entry in the - * table indicates that the receiver should signal the futex at the given - * offset. Offsets are relative to the region, not the shared memory window. - * - * interrupt_signalled_offset is used to reliably signal interrupts across the - * vmm boundary. There are two roles: transmitter and receiver. For example, - * in the host_to_guest_signal_table the host is the transmitter and the - * guest is the receiver. The protocol is as follows: - * - * 1. The transmitter should convert the offset of the futex to an offset - * in the signal table [0, (1 << num_nodes_lg2)) - * The transmitter can choose any appropriate hashing algorithm, including - * hash = futex_offset & ((1 << num_nodes_lg2) - 1) - * - * 3. The transmitter should atomically compare and swap futex_offset with 0 - * at hash. There are 3 possible outcomes - * a. The swap fails because the futex_offset is already in the table. - * The transmitter should stop. - * b. Some other offset is in the table. This is a hash collision. The - * transmitter should move to another table slot and try again. One - * possible algorithm: - * hash = (hash + 1) & ((1 << num_nodes_lg2) - 1) - * c. The swap worked. Continue below. - * - * 3. The transmitter atomically swaps 1 with the value at the - * interrupt_signalled_offset. There are two outcomes: - * a. The prior value was 1. In this case an interrupt has already been - * posted. The transmitter is done. - * b. The prior value was 0, indicating that the receiver may be sleeping. - * The transmitter will issue an interrupt. - * - * 4. On waking the receiver immediately exchanges a 0 with the - * interrupt_signalled_offset. If it receives a 0 then this a spurious - * interrupt. That may occasionally happen in the current protocol, but - * should be rare. - * - * 5. The receiver scans the signal table by atomicaly exchanging 0 at each - * location. If a non-zero offset is returned from the exchange the - * receiver wakes all sleepers at the given offset: - * futex((int*)(region_base + old_value), FUTEX_WAKE, MAX_INT); - * - * 6. The receiver thread then does a conditional wait, waking immediately - * if the value at interrupt_signalled_offset is non-zero. This catches cases - * here additional signals were posted while the table was being scanned. - * On the guest the wait is handled via the VSOC_WAIT_FOR_INCOMING_INTERRUPT - * ioctl. - */ -struct vsoc_signal_table_layout { - /* log_2(Number of signal table entries) */ - __u32 num_nodes_lg2; - /* - * Offset to the first signal table entry relative to the start of the - * region - */ - __u32 futex_uaddr_table_offset; - /* - * Offset to an atomic_t / atomic uint32_t. A non-zero value indicates - * that one or more offsets are currently posted in the table. - * semi-unique access to an entry in the table - */ - __u32 interrupt_signalled_offset; -}; - -#define VSOC_REGION_WHOLE ((__s32)0) -#define VSOC_DEVICE_NAME_SZ 16 - -/** - * Each HAL would (usually) talk to a single device region - * Mulitple entities care about these regions: - * - The ivshmem_server will populate the regions in shared memory - * - The guest kernel will read the region, create minor device nodes, and - * allow interested parties to register for FUTEX_WAKE events in the region - * - HALs will access via the minor device nodes published by the guest kernel - * - Host side processes will access the region via the ivshmem_server: - * 1. Pass name to ivshmem_server at a UNIX socket - * 2. ivshmemserver will reply with 2 fds: - * - host->guest doorbell fd - * - guest->host doorbell fd - * - fd for the shared memory region - * - region offset - * 3. Start a futex receiver thread on the doorbell fd pointed at the - * signal_nodes - */ -struct vsoc_device_region { - __u16 current_version; - __u16 min_compatible_version; - __u32 region_begin_offset; - __u32 region_end_offset; - __u32 offset_of_region_data; - struct vsoc_signal_table_layout guest_to_host_signal_table; - struct vsoc_signal_table_layout host_to_guest_signal_table; - /* Name of the device. Must always be terminated with a '\0', so - * the longest supported device name is 15 characters. - */ - char device_name[VSOC_DEVICE_NAME_SZ]; - /* There are two ways that permissions to access regions are handled: - * - When subdivided_by is VSOC_REGION_WHOLE, any process that can - * open the device node for the region gains complete access to it. - * - When subdivided is set processes that open the region cannot - * access it. Access to a sub-region must be established by invoking - * the VSOC_CREATE_FD_SCOPE_PERMISSION ioctl on the region - * referenced in subdivided_by, providing a fileinstance - * (represented by a fd) opened on this region. - */ - __u32 managed_by; -}; - -/* - * The vsoc layout descriptor. - * The first 4K should be reserved for the shm header and region descriptors. - * The regions should be page aligned. - */ - -struct vsoc_shm_layout_descriptor { - __u16 major_version; - __u16 minor_version; - - /* size of the shm. This may be redundant but nice to have */ - __u32 size; - - /* number of shared memory regions */ - __u32 region_count; - - /* The offset to the start of region descriptors */ - __u32 vsoc_region_desc_offset; -}; - -/* - * This specifies the current version that should be stored in - * vsoc_shm_layout_descriptor.major_version and - * vsoc_shm_layout_descriptor.minor_version. - * It should be updated only if the vsoc_device_region and - * vsoc_shm_layout_descriptor structures have changed. - * Versioning within each region is transferred - * via the min_compatible_version and current_version fields in - * vsoc_device_region. The driver does not consult these fields: they are left - * for the HALs and host processes and will change independently of the layout - * version. - */ -#define CURRENT_VSOC_LAYOUT_MAJOR_VERSION 2 -#define CURRENT_VSOC_LAYOUT_MINOR_VERSION 0 - -#define VSOC_CREATE_FD_SCOPED_PERMISSION \ - _IOW(0xF5, 0, struct fd_scoped_permission) -#define VSOC_GET_FD_SCOPED_PERMISSION _IOR(0xF5, 1, struct fd_scoped_permission) - -/* - * This is used to signal the host to scan the guest_to_host_signal_table - * for new futexes to wake. This sends an interrupt if one is not already - * in flight. - */ -#define VSOC_MAYBE_SEND_INTERRUPT_TO_HOST _IO(0xF5, 2) - -/* - * When this returns the guest will scan host_to_guest_signal_table to - * check for new futexes to wake. - */ -/* TODO(ghartman): Consider moving this to the bottom half */ -#define VSOC_WAIT_FOR_INCOMING_INTERRUPT _IO(0xF5, 3) - -/* - * Guest HALs will use this to retrieve the region description after - * opening their device node. - */ -#define VSOC_DESCRIBE_REGION _IOR(0xF5, 4, struct vsoc_device_region) - -/* - * Wake any threads that may be waiting for a host interrupt on this region. - * This is mostly used during shutdown. - */ -#define VSOC_SELF_INTERRUPT _IO(0xF5, 5) - -/* - * This is used to signal the host to scan the guest_to_host_signal_table - * for new futexes to wake. This sends an interrupt unconditionally. - */ -#define VSOC_SEND_INTERRUPT_TO_HOST _IO(0xF5, 6) - -enum wait_types { - VSOC_WAIT_UNDEFINED = 0, - VSOC_WAIT_IF_EQUAL = 1, - VSOC_WAIT_IF_EQUAL_TIMEOUT = 2 -}; - -/* - * Wait for a condition to be true - * - * Note, this is sized and aligned so the 32 bit and 64 bit layouts are - * identical. - */ -struct vsoc_cond_wait { - /* Input: Offset of the 32 bit word to check */ - __u32 offset; - /* Input: Value that will be compared with the offset */ - __u32 value; - /* Monotonic time to wake at in seconds */ - __u64 wake_time_sec; - /* Input: Monotonic time to wait in nanoseconds */ - __u32 wake_time_nsec; - /* Input: Type of wait */ - __u32 wait_type; - /* Output: Number of times the thread woke before returning. */ - __u32 wakes; - /* Ensure that we're 8-byte aligned and 8 byte length for 32/64 bit - * compatibility. - */ - __u32 reserved_1; -}; - -#define VSOC_COND_WAIT _IOWR(0xF5, 7, struct vsoc_cond_wait) - -/* Wake any local threads waiting at the offset given in arg */ -#define VSOC_COND_WAKE _IO(0xF5, 8) - -#endif /* _UAPI_LINUX_VSOC_SHM_H */ diff --git a/drivers/staging/android/vsoc.c b/drivers/staging/android/vsoc.c deleted file mode 100644 index 1240bb0317d9..000000000000 --- a/drivers/staging/android/vsoc.c +++ /dev/null @@ -1,1149 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * drivers/android/staging/vsoc.c - * - * Android Virtual System on a Chip (VSoC) driver - * - * Copyright (C) 2017 Google, Inc. - * - * Author: ghartman@google.com - * - * Based on drivers/char/kvm_ivshmem.c - driver for KVM Inter-VM shared memory - * Copyright 2009 Cam Macdonell <cam@cs.ualberta.ca> - * - * Based on cirrusfb.c and 8139cp.c: - * Copyright 1999-2001 Jeff Garzik - * Copyright 2001-2004 Jeff Garzik - */ - -#include <linux/dma-mapping.h> -#include <linux/freezer.h> -#include <linux/futex.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/mutex.h> -#include <linux/pci.h> -#include <linux/proc_fs.h> -#include <linux/sched.h> -#include <linux/syscalls.h> -#include <linux/uaccess.h> -#include <linux/interrupt.h> -#include <linux/cdev.h> -#include <linux/file.h> -#include "uapi/vsoc_shm.h" - -#define VSOC_DEV_NAME "vsoc" - -/* - * Description of the ivshmem-doorbell PCI device used by QEmu. These - * constants follow docs/specs/ivshmem-spec.txt, which can be found in - * the QEmu repository. This was last reconciled with the version that - * came out with 2.8 - */ - -/* - * These constants are determined KVM Inter-VM shared memory device - * register offsets - */ -enum { - INTR_MASK = 0x00, /* Interrupt Mask */ - INTR_STATUS = 0x04, /* Interrupt Status */ - IV_POSITION = 0x08, /* VM ID */ - DOORBELL = 0x0c, /* Doorbell */ -}; - -static const int REGISTER_BAR; /* Equal to 0 */ -static const int MAX_REGISTER_BAR_LEN = 0x100; -/* - * The MSI-x BAR is not used directly. - * - * static const int MSI_X_BAR = 1; - */ -static const int SHARED_MEMORY_BAR = 2; - -struct vsoc_region_data { - char name[VSOC_DEVICE_NAME_SZ + 1]; - wait_queue_head_t interrupt_wait_queue; - /* TODO(b/73664181): Use multiple futex wait queues */ - wait_queue_head_t futex_wait_queue; - /* Flag indicating that an interrupt has been signalled by the host. */ - atomic_t *incoming_signalled; - /* Flag indicating the guest has signalled the host. */ - atomic_t *outgoing_signalled; - bool irq_requested; - bool device_created; -}; - -struct vsoc_device { - /* Kernel virtual address of REGISTER_BAR. */ - void __iomem *regs; - /* Physical address of SHARED_MEMORY_BAR. */ - phys_addr_t shm_phys_start; - /* Kernel virtual address of SHARED_MEMORY_BAR. */ - void __iomem *kernel_mapped_shm; - /* Size of the entire shared memory window in bytes. */ - size_t shm_size; - /* - * Pointer to the virtual address of the shared memory layout structure. - * This is probably identical to kernel_mapped_shm, but saving this - * here saves a lot of annoying casts. - */ - struct vsoc_shm_layout_descriptor *layout; - /* - * Points to a table of region descriptors in the kernel's virtual - * address space. Calculated from - * vsoc_shm_layout_descriptor.vsoc_region_desc_offset - */ - struct vsoc_device_region *regions; - /* Head of a list of permissions that have been granted. */ - struct list_head permissions; - struct pci_dev *dev; - /* Per-region (and therefore per-interrupt) information. */ - struct vsoc_region_data *regions_data; - /* - * Table of msi-x entries. This has to be separated from struct - * vsoc_region_data because the kernel deals with them as an array. - */ - struct msix_entry *msix_entries; - /* Mutex that protectes the permission list */ - struct mutex mtx; - /* Major number assigned by the kernel */ - int major; - /* Character device assigned by the kernel */ - struct cdev cdev; - /* Device class assigned by the kernel */ - struct class *class; - /* - * Flags that indicate what we've initialized. These are used to do an - * orderly cleanup of the device. - */ - bool enabled_device; - bool requested_regions; - bool cdev_added; - bool class_added; - bool msix_enabled; -}; - -static struct vsoc_device vsoc_dev; - -/* - * TODO(ghartman): Add a /sys filesystem entry that summarizes the permissions. - */ - -struct fd_scoped_permission_node { - struct fd_scoped_permission permission; - struct list_head list; -}; - -struct vsoc_private_data { - struct fd_scoped_permission_node *fd_scoped_permission_node; -}; - -static long vsoc_ioctl(struct file *, unsigned int, unsigned long); -static int vsoc_mmap(struct file *, struct vm_area_struct *); -static int vsoc_open(struct inode *, struct file *); -static int vsoc_release(struct inode *, struct file *); -static ssize_t vsoc_read(struct file *, char __user *, size_t, loff_t *); -static ssize_t vsoc_write(struct file *, const char __user *, size_t, loff_t *); -static loff_t vsoc_lseek(struct file *filp, loff_t offset, int origin); -static int -do_create_fd_scoped_permission(struct vsoc_device_region *region_p, - struct fd_scoped_permission_node *np, - struct fd_scoped_permission_arg __user *arg); -static void -do_destroy_fd_scoped_permission(struct vsoc_device_region *owner_region_p, - struct fd_scoped_permission *perm); -static long do_vsoc_describe_region(struct file *, - struct vsoc_device_region __user *); -static ssize_t vsoc_get_area(struct file *filp, __u32 *perm_off); - -/** - * Validate arguments on entry points to the driver. - */ -inline int vsoc_validate_inode(struct inode *inode) -{ - if (iminor(inode) >= vsoc_dev.layout->region_count) { - dev_err(&vsoc_dev.dev->dev, - "describe_region: invalid region %d\n", iminor(inode)); - return -ENODEV; - } - return 0; -} - -inline int vsoc_validate_filep(struct file *filp) -{ - int ret = vsoc_validate_inode(file_inode(filp)); - - if (ret) - return ret; - if (!filp->private_data) { - dev_err(&vsoc_dev.dev->dev, - "No private data on fd, region %d\n", - iminor(file_inode(filp))); - return -EBADFD; - } - return 0; -} - -/* Converts from shared memory offset to virtual address */ -static inline void *shm_off_to_virtual_addr(__u32 offset) -{ - return (void __force *)vsoc_dev.kernel_mapped_shm + offset; -} - -/* Converts from shared memory offset to physical address */ -static inline phys_addr_t shm_off_to_phys_addr(__u32 offset) -{ - return vsoc_dev.shm_phys_start + offset; -} - -/** - * Convenience functions to obtain the region from the inode or file. - * Dangerous to call before validating the inode/file. - */ -static -inline struct vsoc_device_region *vsoc_region_from_inode(struct inode *inode) -{ - return &vsoc_dev.regions[iminor(inode)]; -} - -static -inline struct vsoc_device_region *vsoc_region_from_filep(struct file *inode) -{ - return vsoc_region_from_inode(file_inode(inode)); -} - -static inline uint32_t vsoc_device_region_size(struct vsoc_device_region *r) -{ - return r->region_end_offset - r->region_begin_offset; -} - -static const struct file_operations vsoc_ops = { - .owner = THIS_MODULE, - .open = vsoc_open, - .mmap = vsoc_mmap, - .read = vsoc_read, - .unlocked_ioctl = vsoc_ioctl, - .compat_ioctl = vsoc_ioctl, - .write = vsoc_write, - .llseek = vsoc_lseek, - .release = vsoc_release, -}; - -static struct pci_device_id vsoc_id_table[] = { - {0x1af4, 0x1110, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, - {0}, -}; - -MODULE_DEVICE_TABLE(pci, vsoc_id_table); - -static void vsoc_remove_device(struct pci_dev *pdev); -static int vsoc_probe_device(struct pci_dev *pdev, - const struct pci_device_id *ent); - -static struct pci_driver vsoc_pci_driver = { - .name = "vsoc", - .id_table = vsoc_id_table, - .probe = vsoc_probe_device, - .remove = vsoc_remove_device, -}; - -static int -do_create_fd_scoped_permission(struct vsoc_device_region *region_p, - struct fd_scoped_permission_node *np, - struct fd_scoped_permission_arg __user *arg) -{ - struct file *managed_filp; - s32 managed_fd; - atomic_t *owner_ptr = NULL; - struct vsoc_device_region *managed_region_p; - - if (copy_from_user(&np->permission, - &arg->perm, sizeof(np->permission)) || - copy_from_user(&managed_fd, - &arg->managed_region_fd, sizeof(managed_fd))) { - return -EFAULT; - } - managed_filp = fdget(managed_fd).file; - /* Check that it's a valid fd, */ - if (!managed_filp || vsoc_validate_filep(managed_filp)) - return -EPERM; - /* EEXIST if the given fd already has a permission. */ - if (((struct vsoc_private_data *)managed_filp->private_data)-> - fd_scoped_permission_node) - return -EEXIST; - managed_region_p = vsoc_region_from_filep(managed_filp); - /* Check that the provided region is managed by this one */ - if (&vsoc_dev.regions[managed_region_p->managed_by] != region_p) - return -EPERM; - /* The area must be well formed and have non-zero size */ - if (np->permission.begin_offset >= np->permission.end_offset) - return -EINVAL; - /* The area must fit in the memory window */ - if (np->permission.end_offset > - vsoc_device_region_size(managed_region_p)) - return -ERANGE; - /* The area must be in the region data section */ - if (np->permission.begin_offset < - managed_region_p->offset_of_region_data) - return -ERANGE; - /* The area must be page aligned */ - if (!PAGE_ALIGNED(np->permission.begin_offset) || - !PAGE_ALIGNED(np->permission.end_offset)) - return -EINVAL; - /* Owner offset must be naturally aligned in the window */ - if (np->permission.owner_offset & - (sizeof(np->permission.owner_offset) - 1)) - return -EINVAL; - /* The owner flag must reside in the owner memory */ - if (np->permission.owner_offset + sizeof(np->permission.owner_offset) > - vsoc_device_region_size(region_p)) - return -ERANGE; - /* The owner flag must reside in the data section */ - if (np->permission.owner_offset < region_p->offset_of_region_data) - return -EINVAL; - /* The owner value must change to claim the memory */ - if (np->permission.owned_value == VSOC_REGION_FREE) - return -EINVAL; - owner_ptr = - (atomic_t *)shm_off_to_virtual_addr(region_p->region_begin_offset + - np->permission.owner_offset); - /* We've already verified that this is in the shared memory window, so - * it should be safe to write to this address. - */ - if (atomic_cmpxchg(owner_ptr, - VSOC_REGION_FREE, - np->permission.owned_value) != VSOC_REGION_FREE) { - return -EBUSY; - } - ((struct vsoc_private_data *)managed_filp->private_data)-> - fd_scoped_permission_node = np; - /* The file offset needs to be adjusted if the calling - * process did any read/write operations on the fd - * before creating the permission. - */ - if (managed_filp->f_pos) { - if (managed_filp->f_pos > np->permission.end_offset) { - /* If the offset is beyond the permission end, set it - * to the end. - */ - managed_filp->f_pos = np->permission.end_offset; - } else { - /* If the offset is within the permission interval - * keep it there otherwise reset it to zero. - */ - if (managed_filp->f_pos < np->permission.begin_offset) { - managed_filp->f_pos = 0; - } else { - managed_filp->f_pos -= - np->permission.begin_offset; - } - } - } - return 0; -} - -static void -do_destroy_fd_scoped_permission_node(struct vsoc_device_region *owner_region_p, - struct fd_scoped_permission_node *node) -{ - if (node) { - do_destroy_fd_scoped_permission(owner_region_p, - &node->permission); - mutex_lock(&vsoc_dev.mtx); - list_del(&node->list); - mutex_unlock(&vsoc_dev.mtx); - kfree(node); - } -} - -static void -do_destroy_fd_scoped_permission(struct vsoc_device_region *owner_region_p, - struct fd_scoped_permission *perm) -{ - atomic_t *owner_ptr = NULL; - int prev = 0; - - if (!perm) - return; - owner_ptr = (atomic_t *)shm_off_to_virtual_addr - (owner_region_p->region_begin_offset + perm->owner_offset); - prev = atomic_xchg(owner_ptr, VSOC_REGION_FREE); - if (prev != perm->owned_value) - dev_err(&vsoc_dev.dev->dev, - "%x-%x: owner (%s) %x: expected to be %x was %x", - perm->begin_offset, perm->end_offset, - owner_region_p->device_name, perm->owner_offset, - perm->owned_value, prev); -} - -static long do_vsoc_describe_region(struct file *filp, - struct vsoc_device_region __user *dest) -{ - struct vsoc_device_region *region_p; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - region_p = vsoc_region_from_filep(filp); - if (copy_to_user(dest, region_p, sizeof(*region_p))) - return -EFAULT; - return 0; -} - -/** - * Implements the inner logic of cond_wait. Copies to and from userspace are - * done in the helper function below. - */ -static int handle_vsoc_cond_wait(struct file *filp, struct vsoc_cond_wait *arg) -{ - DEFINE_WAIT(wait); - u32 region_number = iminor(file_inode(filp)); - struct vsoc_region_data *data = vsoc_dev.regions_data + region_number; - struct hrtimer_sleeper timeout, *to = NULL; - int ret = 0; - struct vsoc_device_region *region_p = vsoc_region_from_filep(filp); - atomic_t *address = NULL; - ktime_t wake_time; - - /* Ensure that the offset is aligned */ - if (arg->offset & (sizeof(uint32_t) - 1)) - return -EADDRNOTAVAIL; - /* Ensure that the offset is within shared memory */ - if (((uint64_t)arg->offset) + region_p->region_begin_offset + - sizeof(uint32_t) > region_p->region_end_offset) - return -E2BIG; - address = shm_off_to_virtual_addr(region_p->region_begin_offset + - arg->offset); - - /* Ensure that the type of wait is valid */ - switch (arg->wait_type) { - case VSOC_WAIT_IF_EQUAL: - break; - case VSOC_WAIT_IF_EQUAL_TIMEOUT: - to = &timeout; - break; - default: - return -EINVAL; - } - - if (to) { - /* Copy the user-supplied timesec into the kernel structure. - * We do things this way to flatten differences between 32 bit - * and 64 bit timespecs. - */ - if (arg->wake_time_nsec >= NSEC_PER_SEC) - return -EINVAL; - wake_time = ktime_set(arg->wake_time_sec, arg->wake_time_nsec); - - hrtimer_init_sleeper_on_stack(to, CLOCK_MONOTONIC, - HRTIMER_MODE_ABS); - hrtimer_set_expires_range_ns(&to->timer, wake_time, - current->timer_slack_ns); - } - - while (1) { - prepare_to_wait(&data->futex_wait_queue, &wait, - TASK_INTERRUPTIBLE); - /* - * Check the sentinel value after prepare_to_wait. If the value - * changes after this check the writer will call signal, - * changing the task state from INTERRUPTIBLE to RUNNING. That - * will ensure that schedule() will eventually schedule this - * task. - */ - if (atomic_read(address) != arg->value) { - ret = 0; - break; - } - if (to) { - hrtimer_sleeper_start_expires(to, HRTIMER_MODE_ABS); - if (likely(to->task)) - freezable_schedule(); - hrtimer_cancel(&to->timer); - if (!to->task) { - ret = -ETIMEDOUT; - break; - } - } else { - freezable_schedule(); - } - /* Count the number of times that we woke up. This is useful - * for unit testing. - */ - ++arg->wakes; - if (signal_pending(current)) { - ret = -EINTR; - break; - } - } - finish_wait(&data->futex_wait_queue, &wait); - if (to) - destroy_hrtimer_on_stack(&to->timer); - return ret; -} - -/** - * Handles the details of copying from/to userspace to ensure that the copies - * happen on all of the return paths of cond_wait. - */ -static int do_vsoc_cond_wait(struct file *filp, - struct vsoc_cond_wait __user *untrusted_in) -{ - struct vsoc_cond_wait arg; - int rval = 0; - - if (copy_from_user(&arg, untrusted_in, sizeof(arg))) - return -EFAULT; - /* wakes is an out parameter. Initialize it to something sensible. */ - arg.wakes = 0; - rval = handle_vsoc_cond_wait(filp, &arg); - if (copy_to_user(untrusted_in, &arg, sizeof(arg))) - return -EFAULT; - return rval; -} - -static int do_vsoc_cond_wake(struct file *filp, uint32_t offset) -{ - struct vsoc_device_region *region_p = vsoc_region_from_filep(filp); - u32 region_number = iminor(file_inode(filp)); - struct vsoc_region_data *data = vsoc_dev.regions_data + region_number; - /* Ensure that the offset is aligned */ - if (offset & (sizeof(uint32_t) - 1)) - return -EADDRNOTAVAIL; - /* Ensure that the offset is within shared memory */ - if (((uint64_t)offset) + region_p->region_begin_offset + - sizeof(uint32_t) > region_p->region_end_offset) - return -E2BIG; - /* - * TODO(b/73664181): Use multiple futex wait queues. - * We need to wake every sleeper when the condition changes. Typically - * only a single thread will be waiting on the condition, but there - * are exceptions. The worst case is about 10 threads. - */ - wake_up_interruptible_all(&data->futex_wait_queue); - return 0; -} - -static long vsoc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) -{ - int rv = 0; - struct vsoc_device_region *region_p; - u32 reg_num; - struct vsoc_region_data *reg_data; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - region_p = vsoc_region_from_filep(filp); - reg_num = iminor(file_inode(filp)); - reg_data = vsoc_dev.regions_data + reg_num; - switch (cmd) { - case VSOC_CREATE_FD_SCOPED_PERMISSION: - { - struct fd_scoped_permission_node *node = NULL; - - node = kzalloc(sizeof(*node), GFP_KERNEL); - /* We can't allocate memory for the permission */ - if (!node) - return -ENOMEM; - INIT_LIST_HEAD(&node->list); - rv = do_create_fd_scoped_permission - (region_p, - node, - (struct fd_scoped_permission_arg __user *)arg); - if (!rv) { - mutex_lock(&vsoc_dev.mtx); - list_add(&node->list, &vsoc_dev.permissions); - mutex_unlock(&vsoc_dev.mtx); - } else { - kfree(node); - return rv; - } - } - break; - - case VSOC_GET_FD_SCOPED_PERMISSION: - { - struct fd_scoped_permission_node *node = - ((struct vsoc_private_data *)filp->private_data)-> - fd_scoped_permission_node; - if (!node) - return -ENOENT; - if (copy_to_user - ((struct fd_scoped_permission __user *)arg, - &node->permission, sizeof(node->permission))) - return -EFAULT; - } - break; - - case VSOC_MAYBE_SEND_INTERRUPT_TO_HOST: - if (!atomic_xchg(reg_data->outgoing_signalled, 1)) { - writel(reg_num, vsoc_dev.regs + DOORBELL); - return 0; - } else { - return -EBUSY; - } - break; - - case VSOC_SEND_INTERRUPT_TO_HOST: - writel(reg_num, vsoc_dev.regs + DOORBELL); - return 0; - case VSOC_WAIT_FOR_INCOMING_INTERRUPT: - wait_event_interruptible - (reg_data->interrupt_wait_queue, - (atomic_read(reg_data->incoming_signalled) != 0)); - break; - - case VSOC_DESCRIBE_REGION: - return do_vsoc_describe_region - (filp, - (struct vsoc_device_region __user *)arg); - - case VSOC_SELF_INTERRUPT: - atomic_set(reg_data->incoming_signalled, 1); - wake_up_interruptible(®_data->interrupt_wait_queue); - break; - - case VSOC_COND_WAIT: - return do_vsoc_cond_wait(filp, - (struct vsoc_cond_wait __user *)arg); - case VSOC_COND_WAKE: - return do_vsoc_cond_wake(filp, arg); - - default: - return -EINVAL; - } - return 0; -} - -static ssize_t vsoc_read(struct file *filp, char __user *buffer, size_t len, - loff_t *poffset) -{ - __u32 area_off; - const void *area_p; - ssize_t area_len; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - area_len = vsoc_get_area(filp, &area_off); - area_p = shm_off_to_virtual_addr(area_off); - area_p += *poffset; - area_len -= *poffset; - if (area_len <= 0) - return 0; - if (area_len < len) - len = area_len; - if (copy_to_user(buffer, area_p, len)) - return -EFAULT; - *poffset += len; - return len; -} - -static loff_t vsoc_lseek(struct file *filp, loff_t offset, int origin) -{ - ssize_t area_len = 0; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - area_len = vsoc_get_area(filp, NULL); - switch (origin) { - case SEEK_SET: - break; - - case SEEK_CUR: - if (offset > 0 && offset + filp->f_pos < 0) - return -EOVERFLOW; - offset += filp->f_pos; - break; - - case SEEK_END: - if (offset > 0 && offset + area_len < 0) - return -EOVERFLOW; - offset += area_len; - break; - - case SEEK_DATA: - if (offset >= area_len) - return -EINVAL; - if (offset < 0) - offset = 0; - break; - - case SEEK_HOLE: - /* Next hole is always the end of the region, unless offset is - * beyond that - */ - if (offset < area_len) - offset = area_len; - break; - - default: - return -EINVAL; - } - - if (offset < 0 || offset > area_len) - return -EINVAL; - filp->f_pos = offset; - - return offset; -} - -static ssize_t vsoc_write(struct file *filp, const char __user *buffer, - size_t len, loff_t *poffset) -{ - __u32 area_off; - void *area_p; - ssize_t area_len; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - area_len = vsoc_get_area(filp, &area_off); - area_p = shm_off_to_virtual_addr(area_off); - area_p += *poffset; - area_len -= *poffset; - if (area_len <= 0) - return 0; - if (area_len < len) - len = area_len; - if (copy_from_user(area_p, buffer, len)) - return -EFAULT; - *poffset += len; - return len; -} - -static irqreturn_t vsoc_interrupt(int irq, void *region_data_v) -{ - struct vsoc_region_data *region_data = - (struct vsoc_region_data *)region_data_v; - int reg_num = region_data - vsoc_dev.regions_data; - - if (unlikely(!region_data)) - return IRQ_NONE; - - if (unlikely(reg_num < 0 || - reg_num >= vsoc_dev.layout->region_count)) { - dev_err(&vsoc_dev.dev->dev, - "invalid irq @%p reg_num=0x%04x\n", - region_data, reg_num); - return IRQ_NONE; - } - if (unlikely(vsoc_dev.regions_data + reg_num != region_data)) { - dev_err(&vsoc_dev.dev->dev, - "irq not aligned @%p reg_num=0x%04x\n", - region_data, reg_num); - return IRQ_NONE; - } - wake_up_interruptible(®ion_data->interrupt_wait_queue); - return IRQ_HANDLED; -} - -static int vsoc_probe_device(struct pci_dev *pdev, - const struct pci_device_id *ent) -{ - int result; - int i; - resource_size_t reg_size; - dev_t devt; - - vsoc_dev.dev = pdev; - result = pci_enable_device(pdev); - if (result) { - dev_err(&pdev->dev, - "pci_enable_device failed %s: error %d\n", - pci_name(pdev), result); - return result; - } - vsoc_dev.enabled_device = true; - result = pci_request_regions(pdev, "vsoc"); - if (result < 0) { - dev_err(&pdev->dev, "pci_request_regions failed\n"); - vsoc_remove_device(pdev); - return -EBUSY; - } - vsoc_dev.requested_regions = true; - /* Set up the control registers in BAR 0 */ - reg_size = pci_resource_len(pdev, REGISTER_BAR); - if (reg_size > MAX_REGISTER_BAR_LEN) - vsoc_dev.regs = - pci_iomap(pdev, REGISTER_BAR, MAX_REGISTER_BAR_LEN); - else - vsoc_dev.regs = pci_iomap(pdev, REGISTER_BAR, reg_size); - - if (!vsoc_dev.regs) { - dev_err(&pdev->dev, - "cannot map registers of size %zu\n", - (size_t)reg_size); - vsoc_remove_device(pdev); - return -EBUSY; - } - - /* Map the shared memory in BAR 2 */ - vsoc_dev.shm_phys_start = pci_resource_start(pdev, SHARED_MEMORY_BAR); - vsoc_dev.shm_size = pci_resource_len(pdev, SHARED_MEMORY_BAR); - - dev_info(&pdev->dev, "shared memory @ DMA %pa size=0x%zx\n", - &vsoc_dev.shm_phys_start, vsoc_dev.shm_size); - vsoc_dev.kernel_mapped_shm = pci_iomap_wc(pdev, SHARED_MEMORY_BAR, 0); - if (!vsoc_dev.kernel_mapped_shm) { - dev_err(&vsoc_dev.dev->dev, "cannot iomap region\n"); - vsoc_remove_device(pdev); - return -EBUSY; - } - - vsoc_dev.layout = (struct vsoc_shm_layout_descriptor __force *) - vsoc_dev.kernel_mapped_shm; - dev_info(&pdev->dev, "major_version: %d\n", - vsoc_dev.layout->major_version); - dev_info(&pdev->dev, "minor_version: %d\n", - vsoc_dev.layout->minor_version); - dev_info(&pdev->dev, "size: 0x%x\n", vsoc_dev.layout->size); - dev_info(&pdev->dev, "regions: %d\n", vsoc_dev.layout->region_count); - if (vsoc_dev.layout->major_version != - CURRENT_VSOC_LAYOUT_MAJOR_VERSION) { - dev_err(&vsoc_dev.dev->dev, - "driver supports only major_version %d\n", - CURRENT_VSOC_LAYOUT_MAJOR_VERSION); - vsoc_remove_device(pdev); - return -EBUSY; - } - result = alloc_chrdev_region(&devt, 0, vsoc_dev.layout->region_count, - VSOC_DEV_NAME); - if (result) { - dev_err(&vsoc_dev.dev->dev, "alloc_chrdev_region failed\n"); - vsoc_remove_device(pdev); - return -EBUSY; - } - vsoc_dev.major = MAJOR(devt); - cdev_init(&vsoc_dev.cdev, &vsoc_ops); - vsoc_dev.cdev.owner = THIS_MODULE; - result = cdev_add(&vsoc_dev.cdev, devt, vsoc_dev.layout->region_count); - if (result) { - dev_err(&vsoc_dev.dev->dev, "cdev_add error\n"); - vsoc_remove_device(pdev); - return -EBUSY; - } - vsoc_dev.cdev_added = true; - vsoc_dev.class = class_create(THIS_MODULE, VSOC_DEV_NAME); - if (IS_ERR(vsoc_dev.class)) { - dev_err(&vsoc_dev.dev->dev, "class_create failed\n"); - vsoc_remove_device(pdev); - return PTR_ERR(vsoc_dev.class); - } - vsoc_dev.class_added = true; - vsoc_dev.regions = (struct vsoc_device_region __force *) - ((void *)vsoc_dev.layout + - vsoc_dev.layout->vsoc_region_desc_offset); - vsoc_dev.msix_entries = - kcalloc(vsoc_dev.layout->region_count, - sizeof(vsoc_dev.msix_entries[0]), GFP_KERNEL); - if (!vsoc_dev.msix_entries) { - dev_err(&vsoc_dev.dev->dev, - "unable to allocate msix_entries\n"); - vsoc_remove_device(pdev); - return -ENOSPC; - } - vsoc_dev.regions_data = - kcalloc(vsoc_dev.layout->region_count, - sizeof(vsoc_dev.regions_data[0]), GFP_KERNEL); - if (!vsoc_dev.regions_data) { - dev_err(&vsoc_dev.dev->dev, - "unable to allocate regions' data\n"); - vsoc_remove_device(pdev); - return -ENOSPC; - } - for (i = 0; i < vsoc_dev.layout->region_count; ++i) - vsoc_dev.msix_entries[i].entry = i; - - result = pci_enable_msix_exact(vsoc_dev.dev, vsoc_dev.msix_entries, - vsoc_dev.layout->region_count); - if (result) { - dev_info(&pdev->dev, "pci_enable_msix failed: %d\n", result); - vsoc_remove_device(pdev); - return -ENOSPC; - } - /* Check that all regions are well formed */ - for (i = 0; i < vsoc_dev.layout->region_count; ++i) { - const struct vsoc_device_region *region = vsoc_dev.regions + i; - - if (!PAGE_ALIGNED(region->region_begin_offset) || - !PAGE_ALIGNED(region->region_end_offset)) { - dev_err(&vsoc_dev.dev->dev, - "region %d not aligned (%x:%x)", i, - region->region_begin_offset, - region->region_end_offset); - vsoc_remove_device(pdev); - return -EFAULT; - } - if (region->region_begin_offset >= region->region_end_offset || - region->region_end_offset > vsoc_dev.shm_size) { - dev_err(&vsoc_dev.dev->dev, - "region %d offsets are wrong: %x %x %zx", - i, region->region_begin_offset, - region->region_end_offset, vsoc_dev.shm_size); - vsoc_remove_device(pdev); - return -EFAULT; - } - if (region->managed_by >= vsoc_dev.layout->region_count) { - dev_err(&vsoc_dev.dev->dev, - "region %d has invalid owner: %u", - i, region->managed_by); - vsoc_remove_device(pdev); - return -EFAULT; - } - } - vsoc_dev.msix_enabled = true; - for (i = 0; i < vsoc_dev.layout->region_count; ++i) { - const struct vsoc_device_region *region = vsoc_dev.regions + i; - size_t name_sz = sizeof(vsoc_dev.regions_data[i].name) - 1; - const struct vsoc_signal_table_layout *h_to_g_signal_table = - ®ion->host_to_guest_signal_table; - const struct vsoc_signal_table_layout *g_to_h_signal_table = - ®ion->guest_to_host_signal_table; - - vsoc_dev.regions_data[i].name[name_sz] = '\0'; - memcpy(vsoc_dev.regions_data[i].name, region->device_name, - name_sz); - dev_info(&pdev->dev, "region %d name=%s\n", - i, vsoc_dev.regions_data[i].name); - init_waitqueue_head - (&vsoc_dev.regions_data[i].interrupt_wait_queue); - init_waitqueue_head(&vsoc_dev.regions_data[i].futex_wait_queue); - vsoc_dev.regions_data[i].incoming_signalled = - shm_off_to_virtual_addr(region->region_begin_offset) + - h_to_g_signal_table->interrupt_signalled_offset; - vsoc_dev.regions_data[i].outgoing_signalled = - shm_off_to_virtual_addr(region->region_begin_offset) + - g_to_h_signal_table->interrupt_signalled_offset; - result = request_irq(vsoc_dev.msix_entries[i].vector, - vsoc_interrupt, 0, - vsoc_dev.regions_data[i].name, - vsoc_dev.regions_data + i); - if (result) { - dev_info(&pdev->dev, - "request_irq failed irq=%d vector=%d\n", - i, vsoc_dev.msix_entries[i].vector); - vsoc_remove_device(pdev); - return -ENOSPC; - } - vsoc_dev.regions_data[i].irq_requested = true; - if (!device_create(vsoc_dev.class, NULL, - MKDEV(vsoc_dev.major, i), - NULL, vsoc_dev.regions_data[i].name)) { - dev_err(&vsoc_dev.dev->dev, "device_create failed\n"); - vsoc_remove_device(pdev); - return -EBUSY; - } - vsoc_dev.regions_data[i].device_created = true; - } - return 0; -} - -/* - * This should undo all of the allocations in the probe function in reverse - * order. - * - * Notes: - * - * The device may have been partially initialized, so double check - * that the allocations happened. - * - * This function may be called multiple times, so mark resources as freed - * as they are deallocated. - */ -static void vsoc_remove_device(struct pci_dev *pdev) -{ - int i; - /* - * pdev is the first thing to be set on probe and the last thing - * to be cleared here. If it's NULL then there is no cleanup. - */ - if (!pdev || !vsoc_dev.dev) - return; - dev_info(&pdev->dev, "remove_device\n"); - if (vsoc_dev.regions_data) { - for (i = 0; i < vsoc_dev.layout->region_count; ++i) { - if (vsoc_dev.regions_data[i].device_created) { - device_destroy(vsoc_dev.class, - MKDEV(vsoc_dev.major, i)); - vsoc_dev.regions_data[i].device_created = false; - } - if (vsoc_dev.regions_data[i].irq_requested) - free_irq(vsoc_dev.msix_entries[i].vector, NULL); - vsoc_dev.regions_data[i].irq_requested = false; - } - kfree(vsoc_dev.regions_data); - vsoc_dev.regions_data = NULL; - } - if (vsoc_dev.msix_enabled) { - pci_disable_msix(pdev); - vsoc_dev.msix_enabled = false; - } - kfree(vsoc_dev.msix_entries); - vsoc_dev.msix_entries = NULL; - vsoc_dev.regions = NULL; - if (vsoc_dev.class_added) { - class_destroy(vsoc_dev.class); - vsoc_dev.class_added = false; - } - if (vsoc_dev.cdev_added) { - cdev_del(&vsoc_dev.cdev); - vsoc_dev.cdev_added = false; - } - if (vsoc_dev.major && vsoc_dev.layout) { - unregister_chrdev_region(MKDEV(vsoc_dev.major, 0), - vsoc_dev.layout->region_count); - vsoc_dev.major = 0; - } - vsoc_dev.layout = NULL; - if (vsoc_dev.kernel_mapped_shm) { - pci_iounmap(pdev, vsoc_dev.kernel_mapped_shm); - vsoc_dev.kernel_mapped_shm = NULL; - } - if (vsoc_dev.regs) { - pci_iounmap(pdev, vsoc_dev.regs); - vsoc_dev.regs = NULL; - } - if (vsoc_dev.requested_regions) { - pci_release_regions(pdev); - vsoc_dev.requested_regions = false; - } - if (vsoc_dev.enabled_device) { - pci_disable_device(pdev); - vsoc_dev.enabled_device = false; - } - /* Do this last: it indicates that the device is not initialized. */ - vsoc_dev.dev = NULL; -} - -static void __exit vsoc_cleanup_module(void) -{ - vsoc_remove_device(vsoc_dev.dev); - pci_unregister_driver(&vsoc_pci_driver); -} - -static int __init vsoc_init_module(void) -{ - int err = -ENOMEM; - - INIT_LIST_HEAD(&vsoc_dev.permissions); - mutex_init(&vsoc_dev.mtx); - - err = pci_register_driver(&vsoc_pci_driver); - if (err < 0) - return err; - return 0; -} - -static int vsoc_open(struct inode *inode, struct file *filp) -{ - /* Can't use vsoc_validate_filep because filp is still incomplete */ - int ret = vsoc_validate_inode(inode); - - if (ret) - return ret; - filp->private_data = - kzalloc(sizeof(struct vsoc_private_data), GFP_KERNEL); - if (!filp->private_data) - return -ENOMEM; - return 0; -} - -static int vsoc_release(struct inode *inode, struct file *filp) -{ - struct vsoc_private_data *private_data = NULL; - struct fd_scoped_permission_node *node = NULL; - struct vsoc_device_region *owner_region_p = NULL; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - private_data = (struct vsoc_private_data *)filp->private_data; - if (!private_data) - return 0; - - node = private_data->fd_scoped_permission_node; - if (node) { - owner_region_p = vsoc_region_from_inode(inode); - if (owner_region_p->managed_by != VSOC_REGION_WHOLE) { - owner_region_p = - &vsoc_dev.regions[owner_region_p->managed_by]; - } - do_destroy_fd_scoped_permission_node(owner_region_p, node); - private_data->fd_scoped_permission_node = NULL; - } - kfree(private_data); - filp->private_data = NULL; - - return 0; -} - -/* - * Returns the device relative offset and length of the area specified by the - * fd scoped permission. If there is no fd scoped permission set, a default - * permission covering the entire region is assumed, unless the region is owned - * by another one, in which case the default is a permission with zero size. - */ -static ssize_t vsoc_get_area(struct file *filp, __u32 *area_offset) -{ - __u32 off = 0; - ssize_t length = 0; - struct vsoc_device_region *region_p; - struct fd_scoped_permission *perm; - - region_p = vsoc_region_from_filep(filp); - off = region_p->region_begin_offset; - perm = &((struct vsoc_private_data *)filp->private_data)-> - fd_scoped_permission_node->permission; - if (perm) { - off += perm->begin_offset; - length = perm->end_offset - perm->begin_offset; - } else if (region_p->managed_by == VSOC_REGION_WHOLE) { - /* No permission set and the regions is not owned by another, - * default to full region access. - */ - length = vsoc_device_region_size(region_p); - } else { - /* return zero length, access is denied. */ - length = 0; - } - if (area_offset) - *area_offset = off; - return length; -} - -static int vsoc_mmap(struct file *filp, struct vm_area_struct *vma) -{ - unsigned long len = vma->vm_end - vma->vm_start; - __u32 area_off; - phys_addr_t mem_off; - ssize_t area_len; - int retval = vsoc_validate_filep(filp); - - if (retval) - return retval; - area_len = vsoc_get_area(filp, &area_off); - /* Add the requested offset */ - area_off += (vma->vm_pgoff << PAGE_SHIFT); - area_len -= (vma->vm_pgoff << PAGE_SHIFT); - if (area_len < len) - return -EINVAL; - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - mem_off = shm_off_to_phys_addr(area_off); - if (io_remap_pfn_range(vma, vma->vm_start, mem_off >> PAGE_SHIFT, - len, vma->vm_page_prot)) - return -EAGAIN; - return 0; -} - -module_init(vsoc_init_module); -module_exit(vsoc_cleanup_module); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Greg Hartman <ghartman@google.com>"); -MODULE_DESCRIPTION("VSoC interpretation of QEmu's ivshmem device"); -MODULE_VERSION("1.0"); |