text: /*-
   *   BSD LICENSE
   *
   *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   *   All rights reserved.
   *
   *   Redistribution and use in source and binary forms, with or without
   *   modification, are permitted provided that the following conditions
   *   are met:
   *
   *     * Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in
   *       the documentation and/or other materials provided with the
   *       distribution.
   *     * Neither the name of Intel Corporation nor the names of its
   *       contributors may be used to endorse or promote products derived
   *       from this software without specific prior written permission.
   *
   *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef CHANNEL_MANAGER_H_
  #define CHANNEL_MANAGER_H_
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #include <linux/limits.h>
  #include <sys/un.h>
  #include <rte_atomic.h>
  
  /* Maximum number of CPUs */
  #define CHANNEL_CMDS_MAX_CPUS        64
  #if CHANNEL_CMDS_MAX_CPUS > 64
  #error Maximum number of cores is 64, overflow is guaranteed to \
      cause problems with VM Power Management
  #endif
  
  /* Maximum name length including '\0' terminator */
  #define CHANNEL_MGR_MAX_NAME_LEN    64
  
  /* Maximum number of channels to each Virtual Machine */
  #define CHANNEL_MGR_MAX_CHANNELS    64
  
  /* Hypervisor Path for libvirt(qemu/KVM) */
  #define CHANNEL_MGR_DEFAULT_HV_PATH "qemu:///system"
  
  /* File socket directory */
  #define CHANNEL_MGR_SOCKET_PATH     "/tmp/powermonitor/"
  
  #ifndef UNIX_PATH_MAX
  struct sockaddr_un _sockaddr_un;
  #define UNIX_PATH_MAX sizeof(_sockaddr_un.sun_path)
  #endif
  
  #define MAX_VMS 4
  #define MAX_VCPUS 20
  
  
  struct libvirt_vm_info {
  	const char *vm_name;
  	unsigned int pcpus[MAX_VCPUS];
  	uint8_t num_cpus;
  };
  
  struct libvirt_vm_info lvm_info[MAX_VMS];
  /* Communication Channel Status */
  enum channel_status { CHANNEL_MGR_CHANNEL_DISCONNECTED = 0,
  	CHANNEL_MGR_CHANNEL_CONNECTED,
  	CHANNEL_MGR_CHANNEL_DISABLED,
  	CHANNEL_MGR_CHANNEL_PROCESSING};
  
  /* VM libvirt(qemu/KVM) connection status */
  enum vm_status { CHANNEL_MGR_VM_INACTIVE = 0, CHANNEL_MGR_VM_ACTIVE};
  
  /*
   *  Represents a single and exclusive VM channel that exists between a guest and
   *  the host.
   */
  struct channel_info {
  	char channel_path[UNIX_PATH_MAX]; /**< Path to host socket */
  	volatile uint32_t status;    /**< Connection status(enum channel_status) */
  	int fd;                      /**< AF_UNIX socket fd */
  	unsigned channel_num;        /**< CHANNEL_MGR_SOCKET_PATH/<vm_name>.channel_num */
  	void *priv_info;             /**< Pointer to private info, do not modify */
  };
  
  /* Represents a single VM instance used to return internal information about
   * a VM */
  struct vm_info {
  	char name[CHANNEL_MGR_MAX_NAME_LEN];          /**< VM name */
  	enum vm_status status;                        /**< libvirt status */
  	uint64_t pcpu_mask[CHANNEL_CMDS_MAX_CPUS];    /**< pCPU mask for each vCPU */
  	unsigned num_vcpus;                           /**< number of vCPUS */
  	struct channel_info channels[CHANNEL_MGR_MAX_CHANNELS]; /**< Array of channel_info */
  	unsigned num_channels;                        /**< Number of channels */
  };
  
  /**
   * Initialize the Channel Manager resources and connect to the Hypervisor
   * specified in path.
   * This must be successfully called first before calling any other functions.
   * It must only be call once;
   *
   * @param path
   *  Must be a local path, e.g. qemu:///system.
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int channel_manager_init(const char *path);
  
  /**
   * Free resources associated with the Channel Manager.
   *
   * @param path
   *  Must be a local path, e.g. qemu:///system.
   *
   * @return
   *  None
   */
  void channel_manager_exit(void);
  
  /**
   * Get the Physical CPU mask for VM lcore channel(vcpu), result is assigned to
   * core_mask.
   * It is not thread-safe.
   *
   * @param chan_info
   *  Pointer to struct channel_info
   *
   * @param vcpu
   *  The virtual CPU to query.
   *
   *
   * @return
   *  - 0 on error.
   *  - >0 on success.
   */
  uint64_t get_pcpus_mask(struct channel_info *chan_info, unsigned vcpu);
  
  /**
   * Set the Physical CPU mask for the specified vCPU.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to lookup
   *
   * @param vcpu
   *  The virtual CPU to set.
   *
   * @param core_mask
   *  The core mask of the physical CPU(s) to bind the vCPU
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int set_pcpus_mask(char *vm_name, unsigned vcpu, uint64_t core_mask);
  
  /**
   * Set the Physical CPU for the specified vCPU.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to lookup
   *
   * @param vcpu
   *  The virtual CPU to set.
   *
   * @param core_num
   *  The core number of the physical CPU(s) to bind the vCPU
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int set_pcpu(char *vm_name, unsigned vcpu, unsigned core_num);
  /**
   * Add a VM as specified by name to the Channel Manager. The name must
   * correspond to a valid libvirt domain name.
   * This is required prior to adding channels.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to lookup.
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int add_vm(const char *name);
  
  /**
   * Remove a previously added Virtual Machine from the Channel Manager
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to lookup.
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int remove_vm(const char *name);
  
  /**
   * Add all available channels to the VM as specified by name.
   * Channels in the form of paths
   * (CHANNEL_MGR_SOCKET_PATH/<vm_name>.<channel_number>) will only be parsed.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to lookup.
   *
   * @return
   *  - N the number of channels added for the VM
   */
  int add_all_channels(const char *vm_name);
  
  /**
   * Add the channel numbers in channel_list to the domain specified by name.
   * Channels in the form of paths
   * (CHANNEL_MGR_SOCKET_PATH/<vm_name>.<channel_number>) will only be parsed.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to add channels.
   *
   * @param channel_list
   *  Pointer to list of unsigned integers, representing the channel number to add
   *  It must be allocated outside of this function.
   *
   * @param num_channels
   *  The amount of channel numbers in channel_list
   *
   * @return
   *  - N the number of channels added for the VM
   *  - 0 for error
   */
  int add_channels(const char *vm_name, unsigned *channel_list,
  		unsigned num_channels);
  
  /**
   * Remove a channel definition from the channel manager. This must only be
   * called from the channel monitor thread.
   *
   * @param chan_info
   *  Pointer to a valid struct channel_info.
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int remove_channel(struct channel_info **chan_info_dptr);
  
  /**
   * For all channels associated with a Virtual Machine name, update the
   * connection status. Valid states are CHANNEL_MGR_CHANNEL_CONNECTED or
   * CHANNEL_MGR_CHANNEL_DISABLED only.
   *
   *
   * @param name
   *  Virtual Machine name to modify all channels.
   *
   * @param status
   *  The status to set each channel
   *
   * @param num_channels
   *  The amount of channel numbers in channel_list
   *
   * @return
   *  - N the number of channels added for the VM
   *  - 0 for error
   */
  int set_channel_status_all(const char *name, enum channel_status status);
  
  /**
   * For all channels in channel_list associated with a Virtual Machine name
   * update the connection status of each.
   * Valid states are CHANNEL_MGR_CHANNEL_CONNECTED or
   * CHANNEL_MGR_CHANNEL_DISABLED only.
   * It is not thread-safe.
   *
   * @param name
   *  Virtual Machine name to add channels.
   *
   * @param channel_list
   *  Pointer to list of unsigned integers, representing the channel numbers to
   *  modify.
   *  It must be allocated outside of this function.
   *
   * @param num_channels
   *  The amount of channel numbers in channel_list
   *
   * @return
   *  - N the number of channels modified for the VM
   *  - 0 for error
   */
  int set_channel_status(const char *vm_name, unsigned *channel_list,
  		unsigned len_channel_list, enum channel_status status);
  
  /**
   * Populates a pointer to struct vm_info associated with vm_name.
   *
   * @param vm_name
   *  The name of the virtual machine to lookup.
   *
   *  @param vm_info
   *   Pointer to a struct vm_info, this must be allocated prior to calling this
   *   function.
   *
   * @return
   *  - 0 on success.
   *  - Negative on error.
   */
  int get_info_vm(const char *vm_name, struct vm_info *info);
  
  /**
   * Populates a table with all domains running and their physical cpu.
   * All information is gathered through libvirt api.
   *
   * @param num_vm
   *  modified to store number of active VMs
   *
   * @param num_vcpu
      modified to store number of vcpus active
   *
   * @return
   *   void
   */
  void get_all_vm(int *num_vm, int *num_vcpu);
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* CHANNEL_MANAGER_H_ */
  