diff options
Diffstat (limited to 'drivers/misc/mic/scif/scif_ports.c')
-rw-r--r-- | drivers/misc/mic/scif/scif_ports.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_ports.c b/drivers/misc/mic/scif/scif_ports.c new file mode 100644 index 000000000..594e18d27 --- /dev/null +++ b/drivers/misc/mic/scif/scif_ports.c @@ -0,0 +1,124 @@ +/* + * Intel MIC Platform Software Stack (MPSS) + * + * Copyright(c) 2014 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * Intel SCIF driver. + * + */ +#include <linux/idr.h> + +#include "scif_main.h" + +#define SCIF_PORT_COUNT 0x10000 /* Ports available */ + +struct idr scif_ports; + +/* + * struct scif_port - SCIF port information + * + * @ref_cnt - Reference count since there can be multiple endpoints + * created via scif_accept(..) simultaneously using a port. + */ +struct scif_port { + int ref_cnt; +}; + +/** + * __scif_get_port - Reserve a specified port # for SCIF and add it + * to the global list. + * @port : port # to be reserved. + * + * @return : Allocated SCIF port #, or -ENOSPC if port unavailable. + * On memory allocation failure, returns -ENOMEM. + */ +static int __scif_get_port(int start, int end) +{ + int id; + struct scif_port *port = kzalloc(sizeof(*port), GFP_ATOMIC); + + if (!port) + return -ENOMEM; + spin_lock(&scif_info.port_lock); + id = idr_alloc(&scif_ports, port, start, end, GFP_ATOMIC); + if (id >= 0) + port->ref_cnt++; + spin_unlock(&scif_info.port_lock); + return id; +} + +/** + * scif_rsrv_port - Reserve a specified port # for SCIF. + * @port : port # to be reserved. + * + * @return : Allocated SCIF port #, or -ENOSPC if port unavailable. + * On memory allocation failure, returns -ENOMEM. + */ +int scif_rsrv_port(u16 port) +{ + return __scif_get_port(port, port + 1); +} + +/** + * scif_get_new_port - Get and reserve any port # for SCIF in the range + * SCIF_PORT_RSVD + 1 to SCIF_PORT_COUNT - 1. + * + * @return : Allocated SCIF port #, or -ENOSPC if no ports available. + * On memory allocation failure, returns -ENOMEM. + */ +int scif_get_new_port(void) +{ + return __scif_get_port(SCIF_PORT_RSVD + 1, SCIF_PORT_COUNT); +} + +/** + * scif_get_port - Increment the reference count for a SCIF port + * @id : SCIF port + * + * @return : None + */ +void scif_get_port(u16 id) +{ + struct scif_port *port; + + if (!id) + return; + spin_lock(&scif_info.port_lock); + port = idr_find(&scif_ports, id); + if (port) + port->ref_cnt++; + spin_unlock(&scif_info.port_lock); +} + +/** + * scif_put_port - Release a reserved SCIF port + * @id : SCIF port to be released. + * + * @return : None + */ +void scif_put_port(u16 id) +{ + struct scif_port *port; + + if (!id) + return; + spin_lock(&scif_info.port_lock); + port = idr_find(&scif_ports, id); + if (port) { + port->ref_cnt--; + if (!port->ref_cnt) { + idr_remove(&scif_ports, id); + kfree(port); + } + } + spin_unlock(&scif_info.port_lock); +} |