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1426 lines
40 KiB
1426 lines
40 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* z/VM IUCV hypervisor console (HVC) device driver |
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* |
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* This HVC device driver provides terminal access using |
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* z/VM IUCV communication paths. |
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* |
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* Copyright IBM Corp. 2008, 2013 |
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* |
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* Author(s): Hendrik Brueckner <[email protected]> |
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*/ |
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#define KMSG_COMPONENT "hvc_iucv" |
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
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|
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#include <linux/types.h> |
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#include <linux/slab.h> |
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#include <asm/ebcdic.h> |
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#include <linux/ctype.h> |
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#include <linux/delay.h> |
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#include <linux/device.h> |
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#include <linux/init.h> |
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#include <linux/mempool.h> |
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#include <linux/moduleparam.h> |
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#include <linux/tty.h> |
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#include <linux/wait.h> |
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#include <net/iucv/iucv.h> |
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|
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#include "hvc_console.h" |
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/* General device driver settings */ |
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#define HVC_IUCV_MAGIC 0xc9e4c3e5 |
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#define MAX_HVC_IUCV_LINES HVC_ALLOC_TTY_ADAPTERS |
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#define MEMPOOL_MIN_NR (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4) |
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|
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/* IUCV TTY message */ |
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#define MSG_VERSION 0x02 /* Message version */ |
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#define MSG_TYPE_ERROR 0x01 /* Error message */ |
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#define MSG_TYPE_TERMENV 0x02 /* Terminal environment variable */ |
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#define MSG_TYPE_TERMIOS 0x04 /* Terminal IO struct update */ |
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#define MSG_TYPE_WINSIZE 0x08 /* Terminal window size update */ |
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#define MSG_TYPE_DATA 0x10 /* Terminal data */ |
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struct iucv_tty_msg { |
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u8 version; /* Message version */ |
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u8 type; /* Message type */ |
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#define MSG_MAX_DATALEN ((u16)(~0)) |
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u16 datalen; /* Payload length */ |
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u8 data[]; /* Payload buffer */ |
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} __attribute__((packed)); |
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#define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data)) |
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|
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enum iucv_state_t { |
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IUCV_DISCONN = 0, |
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IUCV_CONNECTED = 1, |
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IUCV_SEVERED = 2, |
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}; |
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|
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enum tty_state_t { |
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TTY_CLOSED = 0, |
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TTY_OPENED = 1, |
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}; |
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|
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struct hvc_iucv_private { |
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struct hvc_struct *hvc; /* HVC struct reference */ |
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u8 srv_name[8]; /* IUCV service name (ebcdic) */ |
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unsigned char is_console; /* Linux console usage flag */ |
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enum iucv_state_t iucv_state; /* IUCV connection status */ |
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enum tty_state_t tty_state; /* TTY status */ |
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struct iucv_path *path; /* IUCV path pointer */ |
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spinlock_t lock; /* hvc_iucv_private lock */ |
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#define SNDBUF_SIZE (PAGE_SIZE) /* must be < MSG_MAX_DATALEN */ |
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void *sndbuf; /* send buffer */ |
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size_t sndbuf_len; /* length of send buffer */ |
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#define QUEUE_SNDBUF_DELAY (HZ / 25) |
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struct delayed_work sndbuf_work; /* work: send iucv msg(s) */ |
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wait_queue_head_t sndbuf_waitq; /* wait for send completion */ |
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struct list_head tty_outqueue; /* outgoing IUCV messages */ |
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struct list_head tty_inqueue; /* incoming IUCV messages */ |
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struct device *dev; /* device structure */ |
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u8 info_path[16]; /* IUCV path info (dev attr) */ |
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}; |
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struct iucv_tty_buffer { |
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struct list_head list; /* list pointer */ |
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struct iucv_message msg; /* store an IUCV message */ |
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size_t offset; /* data buffer offset */ |
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struct iucv_tty_msg *mbuf; /* buffer to store input/output data */ |
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}; |
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|
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/* IUCV callback handler */ |
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static int hvc_iucv_path_pending(struct iucv_path *, u8 *, u8 *); |
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static void hvc_iucv_path_severed(struct iucv_path *, u8 *); |
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static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *); |
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static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *); |
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/* Kernel module parameter: use one terminal device as default */ |
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static unsigned long hvc_iucv_devices = 1; |
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|
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/* Array of allocated hvc iucv tty lines... */ |
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static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; |
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#define IUCV_HVC_CON_IDX (0) |
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/* List of z/VM user ID filter entries (struct iucv_vmid_filter) */ |
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#define MAX_VMID_FILTER (500) |
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#define FILTER_WILDCARD_CHAR '*' |
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static size_t hvc_iucv_filter_size; |
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static void *hvc_iucv_filter; |
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static const char *hvc_iucv_filter_string; |
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static DEFINE_RWLOCK(hvc_iucv_filter_lock); |
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|
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/* Kmem cache and mempool for iucv_tty_buffer elements */ |
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static struct kmem_cache *hvc_iucv_buffer_cache; |
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static mempool_t *hvc_iucv_mempool; |
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|
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/* IUCV handler callback functions */ |
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static struct iucv_handler hvc_iucv_handler = { |
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.path_pending = hvc_iucv_path_pending, |
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.path_severed = hvc_iucv_path_severed, |
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.message_complete = hvc_iucv_msg_complete, |
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.message_pending = hvc_iucv_msg_pending, |
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}; |
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/** |
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* hvc_iucv_get_private() - Return a struct hvc_iucv_private instance. |
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* @num: The HVC virtual terminal number (vtermno) |
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* |
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* This function returns the struct hvc_iucv_private instance that corresponds |
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* to the HVC virtual terminal number specified as parameter @num. |
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*/ |
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static struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num) |
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{ |
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if ((num < HVC_IUCV_MAGIC) || (num - HVC_IUCV_MAGIC > hvc_iucv_devices)) |
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return NULL; |
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return hvc_iucv_table[num - HVC_IUCV_MAGIC]; |
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} |
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/** |
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* alloc_tty_buffer() - Return a new struct iucv_tty_buffer element. |
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* @size: Size of the internal buffer used to store data. |
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* @flags: Memory allocation flags passed to mempool. |
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* |
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* This function allocates a new struct iucv_tty_buffer element and, optionally, |
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* allocates an internal data buffer with the specified size @size. |
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* The internal data buffer is always allocated with GFP_DMA which is |
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* required for receiving and sending data with IUCV. |
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* Note: The total message size arises from the internal buffer size and the |
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* members of the iucv_tty_msg structure. |
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* The function returns NULL if memory allocation has failed. |
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*/ |
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static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags) |
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{ |
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struct iucv_tty_buffer *bufp; |
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bufp = mempool_alloc(hvc_iucv_mempool, flags); |
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if (!bufp) |
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return NULL; |
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memset(bufp, 0, sizeof(*bufp)); |
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|
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if (size > 0) { |
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bufp->msg.length = MSG_SIZE(size); |
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bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA); |
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if (!bufp->mbuf) { |
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mempool_free(bufp, hvc_iucv_mempool); |
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return NULL; |
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} |
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bufp->mbuf->version = MSG_VERSION; |
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bufp->mbuf->type = MSG_TYPE_DATA; |
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bufp->mbuf->datalen = (u16) size; |
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} |
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return bufp; |
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} |
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/** |
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* destroy_tty_buffer() - destroy struct iucv_tty_buffer element. |
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* @bufp: Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL. |
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*/ |
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static void destroy_tty_buffer(struct iucv_tty_buffer *bufp) |
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{ |
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kfree(bufp->mbuf); |
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mempool_free(bufp, hvc_iucv_mempool); |
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} |
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/** |
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* destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element. |
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* @list: List containing struct iucv_tty_buffer elements. |
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*/ |
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static void destroy_tty_buffer_list(struct list_head *list) |
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{ |
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struct iucv_tty_buffer *ent, *next; |
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list_for_each_entry_safe(ent, next, list, list) { |
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list_del(&ent->list); |
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destroy_tty_buffer(ent); |
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} |
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} |
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|
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/** |
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* hvc_iucv_write() - Receive IUCV message & write data to HVC buffer. |
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* @priv: Pointer to struct hvc_iucv_private |
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* @buf: HVC buffer for writing received terminal data. |
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* @count: HVC buffer size. |
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* @has_more_data: Pointer to an int variable. |
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* |
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* The function picks up pending messages from the input queue and receives |
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* the message data that is then written to the specified buffer @buf. |
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* If the buffer size @count is less than the data message size, the |
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* message is kept on the input queue and @has_more_data is set to 1. |
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* If all message data has been written, the message is removed from |
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* the input queue. |
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* |
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* The function returns the number of bytes written to the terminal, zero if |
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* there are no pending data messages available or if there is no established |
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* IUCV path. |
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* If the IUCV path has been severed, then -EPIPE is returned to cause a |
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* hang up (that is issued by the HVC layer). |
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*/ |
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static int hvc_iucv_write(struct hvc_iucv_private *priv, |
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char *buf, int count, int *has_more_data) |
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{ |
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struct iucv_tty_buffer *rb; |
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int written; |
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int rc; |
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/* immediately return if there is no IUCV connection */ |
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if (priv->iucv_state == IUCV_DISCONN) |
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return 0; |
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/* if the IUCV path has been severed, return -EPIPE to inform the |
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* HVC layer to hang up the tty device. */ |
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if (priv->iucv_state == IUCV_SEVERED) |
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return -EPIPE; |
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/* check if there are pending messages */ |
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if (list_empty(&priv->tty_inqueue)) |
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return 0; |
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/* receive an iucv message and flip data to the tty (ldisc) */ |
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rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list); |
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written = 0; |
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if (!rb->mbuf) { /* message not yet received ... */ |
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/* allocate mem to store msg data; if no memory is available |
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* then leave the buffer on the list and re-try later */ |
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rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA); |
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if (!rb->mbuf) |
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return -ENOMEM; |
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rc = __iucv_message_receive(priv->path, &rb->msg, 0, |
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rb->mbuf, rb->msg.length, NULL); |
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switch (rc) { |
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case 0: /* Successful */ |
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break; |
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case 2: /* No message found */ |
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case 9: /* Message purged */ |
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break; |
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default: |
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written = -EIO; |
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} |
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/* remove buffer if an error has occurred or received data |
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* is not correct */ |
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if (rc || (rb->mbuf->version != MSG_VERSION) || |
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(rb->msg.length != MSG_SIZE(rb->mbuf->datalen))) |
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goto out_remove_buffer; |
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} |
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switch (rb->mbuf->type) { |
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case MSG_TYPE_DATA: |
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written = min_t(int, rb->mbuf->datalen - rb->offset, count); |
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memcpy(buf, rb->mbuf->data + rb->offset, written); |
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if (written < (rb->mbuf->datalen - rb->offset)) { |
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rb->offset += written; |
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*has_more_data = 1; |
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goto out_written; |
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} |
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break; |
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case MSG_TYPE_WINSIZE: |
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if (rb->mbuf->datalen != sizeof(struct winsize)) |
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break; |
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/* The caller must ensure that the hvc is locked, which |
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* is the case when called from hvc_iucv_get_chars() */ |
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__hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data)); |
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break; |
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case MSG_TYPE_ERROR: /* ignored ... */ |
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case MSG_TYPE_TERMENV: /* ignored ... */ |
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case MSG_TYPE_TERMIOS: /* ignored ... */ |
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break; |
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} |
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out_remove_buffer: |
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list_del(&rb->list); |
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destroy_tty_buffer(rb); |
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*has_more_data = !list_empty(&priv->tty_inqueue); |
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out_written: |
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return written; |
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} |
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/** |
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* hvc_iucv_get_chars() - HVC get_chars operation. |
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* @vtermno: HVC virtual terminal number. |
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* @buf: Pointer to a buffer to store data |
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* @count: Size of buffer available for writing |
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* |
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* The HVC thread calls this method to read characters from the back-end. |
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* If an IUCV communication path has been established, pending IUCV messages |
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* are received and data is copied into buffer @buf up to @count bytes. |
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* |
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* Locking: The routine gets called under an irqsave() spinlock; and |
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* the routine locks the struct hvc_iucv_private->lock to call |
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* helper functions. |
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*/ |
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static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count) |
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{ |
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struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno); |
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int written; |
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int has_more_data; |
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if (count <= 0) |
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return 0; |
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if (!priv) |
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return -ENODEV; |
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spin_lock(&priv->lock); |
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has_more_data = 0; |
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written = hvc_iucv_write(priv, buf, count, &has_more_data); |
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spin_unlock(&priv->lock); |
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/* if there are still messages on the queue... schedule another run */ |
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if (has_more_data) |
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hvc_kick(); |
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return written; |
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} |
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/** |
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* hvc_iucv_queue() - Buffer terminal data for sending. |
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* @priv: Pointer to struct hvc_iucv_private instance. |
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* @buf: Buffer containing data to send. |
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* @count: Size of buffer and amount of data to send. |
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* |
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* The function queues data for sending. To actually send the buffered data, |
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* a work queue function is scheduled (with QUEUE_SNDBUF_DELAY). |
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* The function returns the number of data bytes that has been buffered. |
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* |
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* If the device is not connected, data is ignored and the function returns |
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* @count. |
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* If the buffer is full, the function returns 0. |
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* If an existing IUCV communicaton path has been severed, -EPIPE is returned |
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* (that can be passed to HVC layer to cause a tty hangup). |
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*/ |
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static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf, |
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int count) |
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{ |
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size_t len; |
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if (priv->iucv_state == IUCV_DISCONN) |
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return count; /* ignore data */ |
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if (priv->iucv_state == IUCV_SEVERED) |
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return -EPIPE; |
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len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len); |
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if (!len) |
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return 0; |
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memcpy(priv->sndbuf + priv->sndbuf_len, buf, len); |
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priv->sndbuf_len += len; |
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if (priv->iucv_state == IUCV_CONNECTED) |
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schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY); |
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return len; |
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} |
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/** |
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* hvc_iucv_send() - Send an IUCV message containing terminal data. |
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* @priv: Pointer to struct hvc_iucv_private instance. |
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* |
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* If an IUCV communication path has been established, the buffered output data |
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* is sent via an IUCV message and the number of bytes sent is returned. |
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* Returns 0 if there is no established IUCV communication path or |
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* -EPIPE if an existing IUCV communicaton path has been severed. |
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*/ |
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static int hvc_iucv_send(struct hvc_iucv_private *priv) |
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{ |
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struct iucv_tty_buffer *sb; |
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int rc, len; |
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if (priv->iucv_state == IUCV_SEVERED) |
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return -EPIPE; |
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if (priv->iucv_state == IUCV_DISCONN) |
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return -EIO; |
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|
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if (!priv->sndbuf_len) |
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return 0; |
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/* allocate internal buffer to store msg data and also compute total |
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* message length */ |
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sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC); |
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if (!sb) |
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return -ENOMEM; |
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memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len); |
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sb->mbuf->datalen = (u16) priv->sndbuf_len; |
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sb->msg.length = MSG_SIZE(sb->mbuf->datalen); |
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list_add_tail(&sb->list, &priv->tty_outqueue); |
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rc = __iucv_message_send(priv->path, &sb->msg, 0, 0, |
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(void *) sb->mbuf, sb->msg.length); |
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if (rc) { |
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/* drop the message here; however we might want to handle |
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* 0x03 (msg limit reached) by trying again... */ |
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list_del(&sb->list); |
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destroy_tty_buffer(sb); |
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} |
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len = priv->sndbuf_len; |
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priv->sndbuf_len = 0; |
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|
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return len; |
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} |
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|
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/** |
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* hvc_iucv_sndbuf_work() - Send buffered data over IUCV |
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* @work: Work structure. |
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* |
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* This work queue function sends buffered output data over IUCV and, |
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* if not all buffered data could be sent, reschedules itself. |
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*/ |
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static void hvc_iucv_sndbuf_work(struct work_struct *work) |
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{ |
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struct hvc_iucv_private *priv; |
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|
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priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work); |
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spin_lock_bh(&priv->lock); |
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hvc_iucv_send(priv); |
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spin_unlock_bh(&priv->lock); |
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} |
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|
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/** |
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* hvc_iucv_put_chars() - HVC put_chars operation. |
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* @vtermno: HVC virtual terminal number. |
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* @buf: Pointer to an buffer to read data from |
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* @count: Size of buffer available for reading |
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* |
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* The HVC thread calls this method to write characters to the back-end. |
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* The function calls hvc_iucv_queue() to queue terminal data for sending. |
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* |
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* Locking: The method gets called under an irqsave() spinlock; and |
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* locks struct hvc_iucv_private->lock. |
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*/ |
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static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count) |
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{ |
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struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno); |
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int queued; |
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|
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if (count <= 0) |
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return 0; |
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|
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if (!priv) |
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return -ENODEV; |
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|
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spin_lock(&priv->lock); |
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queued = hvc_iucv_queue(priv, buf, count); |
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spin_unlock(&priv->lock); |
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|
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return queued; |
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} |
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|
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/** |
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* hvc_iucv_notifier_add() - HVC notifier for opening a TTY for the first time. |
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* @hp: Pointer to the HVC device (struct hvc_struct) |
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* @id: Additional data (originally passed to hvc_alloc): the index of an struct |
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* hvc_iucv_private instance. |
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* |
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* The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private |
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* instance that is derived from @id. Always returns 0. |
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* |
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* Locking: struct hvc_iucv_private->lock, spin_lock_bh |
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*/ |
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static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id) |
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{ |
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struct hvc_iucv_private *priv; |
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|
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priv = hvc_iucv_get_private(id); |
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if (!priv) |
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return 0; |
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|
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spin_lock_bh(&priv->lock); |
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priv->tty_state = TTY_OPENED; |
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spin_unlock_bh(&priv->lock); |
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|
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return 0; |
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} |
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|
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/** |
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* hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance. |
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* @priv: Pointer to the struct hvc_iucv_private instance. |
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*/ |
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static void hvc_iucv_cleanup(struct hvc_iucv_private *priv) |
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{ |
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destroy_tty_buffer_list(&priv->tty_outqueue); |
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destroy_tty_buffer_list(&priv->tty_inqueue); |
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|
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priv->tty_state = TTY_CLOSED; |
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priv->iucv_state = IUCV_DISCONN; |
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|
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priv->sndbuf_len = 0; |
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} |
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|
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/** |
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* tty_outqueue_empty() - Test if the tty outq is empty |
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* @priv: Pointer to struct hvc_iucv_private instance. |
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*/ |
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static inline int tty_outqueue_empty(struct hvc_iucv_private *priv) |
|
{ |
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int rc; |
|
|
|
spin_lock_bh(&priv->lock); |
|
rc = list_empty(&priv->tty_outqueue); |
|
spin_unlock_bh(&priv->lock); |
|
|
|
return rc; |
|
} |
|
|
|
/** |
|
* flush_sndbuf_sync() - Flush send buffer and wait for completion |
|
* @priv: Pointer to struct hvc_iucv_private instance. |
|
* |
|
* The routine cancels a pending sndbuf work, calls hvc_iucv_send() |
|
* to flush any buffered terminal output data and waits for completion. |
|
*/ |
|
static void flush_sndbuf_sync(struct hvc_iucv_private *priv) |
|
{ |
|
int sync_wait; |
|
|
|
cancel_delayed_work_sync(&priv->sndbuf_work); |
|
|
|
spin_lock_bh(&priv->lock); |
|
hvc_iucv_send(priv); /* force sending buffered data */ |
|
sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */ |
|
spin_unlock_bh(&priv->lock); |
|
|
|
if (sync_wait) |
|
wait_event_timeout(priv->sndbuf_waitq, |
|
tty_outqueue_empty(priv), HZ/10); |
|
} |
|
|
|
/** |
|
* hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up |
|
* @priv: Pointer to hvc_iucv_private structure |
|
* |
|
* This routine severs an existing IUCV communication path and hangs |
|
* up the underlying HVC terminal device. |
|
* The hang-up occurs only if an IUCV communication path is established; |
|
* otherwise there is no need to hang up the terminal device. |
|
* |
|
* The IUCV HVC hang-up is separated into two steps: |
|
* 1. After the IUCV path has been severed, the iucv_state is set to |
|
* IUCV_SEVERED. |
|
* 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the |
|
* IUCV_SEVERED state causes the tty hang-up in the HVC layer. |
|
* |
|
* If the tty has not yet been opened, clean up the hvc_iucv_private |
|
* structure to allow re-connects. |
|
* If the tty has been opened, let get_chars() return -EPIPE to signal |
|
* the HVC layer to hang up the tty and, if so, wake up the HVC thread |
|
* to call get_chars()... |
|
* |
|
* Special notes on hanging up a HVC terminal instantiated as console: |
|
* Hang-up: 1. do_tty_hangup() replaces file ops (= hung_up_tty_fops) |
|
* 2. do_tty_hangup() calls tty->ops->close() for console_filp |
|
* => no hangup notifier is called by HVC (default) |
|
* 2. hvc_close() returns because of tty_hung_up_p(filp) |
|
* => no delete notifier is called! |
|
* Finally, the back-end is not being notified, thus, the tty session is |
|
* kept active (TTY_OPEN) to be ready for re-connects. |
|
* |
|
* Locking: spin_lock(&priv->lock) w/o disabling bh |
|
*/ |
|
static void hvc_iucv_hangup(struct hvc_iucv_private *priv) |
|
{ |
|
struct iucv_path *path; |
|
|
|
path = NULL; |
|
spin_lock(&priv->lock); |
|
if (priv->iucv_state == IUCV_CONNECTED) { |
|
path = priv->path; |
|
priv->path = NULL; |
|
priv->iucv_state = IUCV_SEVERED; |
|
if (priv->tty_state == TTY_CLOSED) |
|
hvc_iucv_cleanup(priv); |
|
else |
|
/* console is special (see above) */ |
|
if (priv->is_console) { |
|
hvc_iucv_cleanup(priv); |
|
priv->tty_state = TTY_OPENED; |
|
} else |
|
hvc_kick(); |
|
} |
|
spin_unlock(&priv->lock); |
|
|
|
/* finally sever path (outside of priv->lock due to lock ordering) */ |
|
if (path) { |
|
iucv_path_sever(path, NULL); |
|
iucv_path_free(path); |
|
} |
|
} |
|
|
|
/** |
|
* hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups. |
|
* @hp: Pointer to the HVC device (struct hvc_struct) |
|
* @id: Additional data (originally passed to hvc_alloc): |
|
* the index of an struct hvc_iucv_private instance. |
|
* |
|
* This routine notifies the HVC back-end that a tty hangup (carrier loss, |
|
* virtual or otherwise) has occurred. |
|
* The z/VM IUCV HVC device driver ignores virtual hangups (vhangup()) |
|
* to keep an existing IUCV communication path established. |
|
* (Background: vhangup() is called from user space (by getty or login) to |
|
* disable writing to the tty by other applications). |
|
* If the tty has been opened and an established IUCV path has been severed |
|
* (we caused the tty hangup), the function calls hvc_iucv_cleanup(). |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id) |
|
{ |
|
struct hvc_iucv_private *priv; |
|
|
|
priv = hvc_iucv_get_private(id); |
|
if (!priv) |
|
return; |
|
|
|
flush_sndbuf_sync(priv); |
|
|
|
spin_lock_bh(&priv->lock); |
|
/* NOTE: If the hangup was scheduled by ourself (from the iucv |
|
* path_servered callback [IUCV_SEVERED]), we have to clean up |
|
* our structure and to set state to TTY_CLOSED. |
|
* If the tty was hung up otherwise (e.g. vhangup()), then we |
|
* ignore this hangup and keep an established IUCV path open... |
|
* (...the reason is that we are not able to connect back to the |
|
* client if we disconnect on hang up) */ |
|
priv->tty_state = TTY_CLOSED; |
|
|
|
if (priv->iucv_state == IUCV_SEVERED) |
|
hvc_iucv_cleanup(priv); |
|
spin_unlock_bh(&priv->lock); |
|
} |
|
|
|
/** |
|
* hvc_iucv_dtr_rts() - HVC notifier for handling DTR/RTS |
|
* @hp: Pointer the HVC device (struct hvc_struct) |
|
* @raise: Non-zero to raise or zero to lower DTR/RTS lines |
|
* |
|
* This routine notifies the HVC back-end to raise or lower DTR/RTS |
|
* lines. Raising DTR/RTS is ignored. Lowering DTR/RTS indicates to |
|
* drop the IUCV connection (similar to hang up the modem). |
|
*/ |
|
static void hvc_iucv_dtr_rts(struct hvc_struct *hp, int raise) |
|
{ |
|
struct hvc_iucv_private *priv; |
|
struct iucv_path *path; |
|
|
|
/* Raising the DTR/RTS is ignored as IUCV connections can be |
|
* established at any times. |
|
*/ |
|
if (raise) |
|
return; |
|
|
|
priv = hvc_iucv_get_private(hp->vtermno); |
|
if (!priv) |
|
return; |
|
|
|
/* Lowering the DTR/RTS lines disconnects an established IUCV |
|
* connection. |
|
*/ |
|
flush_sndbuf_sync(priv); |
|
|
|
spin_lock_bh(&priv->lock); |
|
path = priv->path; /* save reference to IUCV path */ |
|
priv->path = NULL; |
|
priv->iucv_state = IUCV_DISCONN; |
|
spin_unlock_bh(&priv->lock); |
|
|
|
/* Sever IUCV path outside of priv->lock due to lock ordering of: |
|
* priv->lock <--> iucv_table_lock */ |
|
if (path) { |
|
iucv_path_sever(path, NULL); |
|
iucv_path_free(path); |
|
} |
|
} |
|
|
|
/** |
|
* hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time. |
|
* @hp: Pointer to the HVC device (struct hvc_struct) |
|
* @id: Additional data (originally passed to hvc_alloc): |
|
* the index of an struct hvc_iucv_private instance. |
|
* |
|
* This routine notifies the HVC back-end that the last tty device fd has been |
|
* closed. The function cleans up tty resources. The clean-up of the IUCV |
|
* connection is done in hvc_iucv_dtr_rts() and depends on the HUPCL termios |
|
* control setting. |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id) |
|
{ |
|
struct hvc_iucv_private *priv; |
|
|
|
priv = hvc_iucv_get_private(id); |
|
if (!priv) |
|
return; |
|
|
|
flush_sndbuf_sync(priv); |
|
|
|
spin_lock_bh(&priv->lock); |
|
destroy_tty_buffer_list(&priv->tty_outqueue); |
|
destroy_tty_buffer_list(&priv->tty_inqueue); |
|
priv->tty_state = TTY_CLOSED; |
|
priv->sndbuf_len = 0; |
|
spin_unlock_bh(&priv->lock); |
|
} |
|
|
|
/** |
|
* hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID |
|
* @ipvmid: Originating z/VM user ID (right padded with blanks) |
|
* |
|
* Returns 0 if the z/VM user ID that is specified with @ipvmid is permitted to |
|
* connect, otherwise non-zero. |
|
*/ |
|
static int hvc_iucv_filter_connreq(u8 ipvmid[8]) |
|
{ |
|
const char *wildcard, *filter_entry; |
|
size_t i, len; |
|
|
|
/* Note: default policy is ACCEPT if no filter is set */ |
|
if (!hvc_iucv_filter_size) |
|
return 0; |
|
|
|
for (i = 0; i < hvc_iucv_filter_size; i++) { |
|
filter_entry = hvc_iucv_filter + (8 * i); |
|
|
|
/* If a filter entry contains the filter wildcard character, |
|
* reduce the length to match the leading portion of the user |
|
* ID only (wildcard match). Characters following the wildcard |
|
* are ignored. |
|
*/ |
|
wildcard = strnchr(filter_entry, 8, FILTER_WILDCARD_CHAR); |
|
len = (wildcard) ? wildcard - filter_entry : 8; |
|
if (0 == memcmp(ipvmid, filter_entry, len)) |
|
return 0; |
|
} |
|
return 1; |
|
} |
|
|
|
/** |
|
* hvc_iucv_path_pending() - IUCV handler to process a connection request. |
|
* @path: Pending path (struct iucv_path) |
|
* @ipvmid: z/VM system identifier of originator |
|
* @ipuser: User specified data for this path |
|
* (AF_IUCV: port/service name and originator port) |
|
* |
|
* The function uses the @ipuser data to determine if the pending path belongs |
|
* to a terminal managed by this device driver. |
|
* If the path belongs to this driver, ensure that the terminal is not accessed |
|
* multiple times (only one connection to a terminal is allowed). |
|
* If the terminal is not yet connected, the pending path is accepted and is |
|
* associated to the appropriate struct hvc_iucv_private instance. |
|
* |
|
* Returns 0 if @path belongs to a terminal managed by the this device driver; |
|
* otherwise returns -ENODEV in order to dispatch this path to other handlers. |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static int hvc_iucv_path_pending(struct iucv_path *path, u8 *ipvmid, |
|
u8 *ipuser) |
|
{ |
|
struct hvc_iucv_private *priv, *tmp; |
|
u8 wildcard[9] = "lnxhvc "; |
|
int i, rc, find_unused; |
|
u8 nuser_data[16]; |
|
u8 vm_user_id[9]; |
|
|
|
ASCEBC(wildcard, sizeof(wildcard)); |
|
find_unused = !memcmp(wildcard, ipuser, 8); |
|
|
|
/* First, check if the pending path request is managed by this |
|
* IUCV handler: |
|
* - find a disconnected device if ipuser contains the wildcard |
|
* - find the device that matches the terminal ID in ipuser |
|
*/ |
|
priv = NULL; |
|
for (i = 0; i < hvc_iucv_devices; i++) { |
|
tmp = hvc_iucv_table[i]; |
|
if (!tmp) |
|
continue; |
|
|
|
if (find_unused) { |
|
spin_lock(&tmp->lock); |
|
if (tmp->iucv_state == IUCV_DISCONN) |
|
priv = tmp; |
|
spin_unlock(&tmp->lock); |
|
|
|
} else if (!memcmp(tmp->srv_name, ipuser, 8)) |
|
priv = tmp; |
|
if (priv) |
|
break; |
|
} |
|
if (!priv) |
|
return -ENODEV; |
|
|
|
/* Enforce that ipvmid is allowed to connect to us */ |
|
read_lock(&hvc_iucv_filter_lock); |
|
rc = hvc_iucv_filter_connreq(ipvmid); |
|
read_unlock(&hvc_iucv_filter_lock); |
|
if (rc) { |
|
iucv_path_sever(path, ipuser); |
|
iucv_path_free(path); |
|
memcpy(vm_user_id, ipvmid, 8); |
|
vm_user_id[8] = 0; |
|
pr_info("A connection request from z/VM user ID %s " |
|
"was refused\n", vm_user_id); |
|
return 0; |
|
} |
|
|
|
spin_lock(&priv->lock); |
|
|
|
/* If the terminal is already connected or being severed, then sever |
|
* this path to enforce that there is only ONE established communication |
|
* path per terminal. */ |
|
if (priv->iucv_state != IUCV_DISCONN) { |
|
iucv_path_sever(path, ipuser); |
|
iucv_path_free(path); |
|
goto out_path_handled; |
|
} |
|
|
|
/* accept path */ |
|
memcpy(nuser_data, ipuser + 8, 8); /* remote service (for af_iucv) */ |
|
memcpy(nuser_data + 8, ipuser, 8); /* local service (for af_iucv) */ |
|
path->msglim = 0xffff; /* IUCV MSGLIMIT */ |
|
path->flags &= ~IUCV_IPRMDATA; /* TODO: use IUCV_IPRMDATA */ |
|
rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv); |
|
if (rc) { |
|
iucv_path_sever(path, ipuser); |
|
iucv_path_free(path); |
|
goto out_path_handled; |
|
} |
|
priv->path = path; |
|
priv->iucv_state = IUCV_CONNECTED; |
|
|
|
/* store path information */ |
|
memcpy(priv->info_path, ipvmid, 8); |
|
memcpy(priv->info_path + 8, ipuser + 8, 8); |
|
|
|
/* flush buffered output data... */ |
|
schedule_delayed_work(&priv->sndbuf_work, 5); |
|
|
|
out_path_handled: |
|
spin_unlock(&priv->lock); |
|
return 0; |
|
} |
|
|
|
/** |
|
* hvc_iucv_path_severed() - IUCV handler to process a path sever. |
|
* @path: Pending path (struct iucv_path) |
|
* @ipuser: User specified data for this path |
|
* (AF_IUCV: port/service name and originator port) |
|
* |
|
* This function calls the hvc_iucv_hangup() function for the |
|
* respective IUCV HVC terminal. |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static void hvc_iucv_path_severed(struct iucv_path *path, u8 *ipuser) |
|
{ |
|
struct hvc_iucv_private *priv = path->private; |
|
|
|
hvc_iucv_hangup(priv); |
|
} |
|
|
|
/** |
|
* hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message. |
|
* @path: Pending path (struct iucv_path) |
|
* @msg: Pointer to the IUCV message |
|
* |
|
* The function puts an incoming message on the input queue for later |
|
* processing (by hvc_iucv_get_chars() / hvc_iucv_write()). |
|
* If the tty has not yet been opened, the message is rejected. |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static void hvc_iucv_msg_pending(struct iucv_path *path, |
|
struct iucv_message *msg) |
|
{ |
|
struct hvc_iucv_private *priv = path->private; |
|
struct iucv_tty_buffer *rb; |
|
|
|
/* reject messages that exceed max size of iucv_tty_msg->datalen */ |
|
if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) { |
|
iucv_message_reject(path, msg); |
|
return; |
|
} |
|
|
|
spin_lock(&priv->lock); |
|
|
|
/* reject messages if tty has not yet been opened */ |
|
if (priv->tty_state == TTY_CLOSED) { |
|
iucv_message_reject(path, msg); |
|
goto unlock_return; |
|
} |
|
|
|
/* allocate tty buffer to save iucv msg only */ |
|
rb = alloc_tty_buffer(0, GFP_ATOMIC); |
|
if (!rb) { |
|
iucv_message_reject(path, msg); |
|
goto unlock_return; /* -ENOMEM */ |
|
} |
|
rb->msg = *msg; |
|
|
|
list_add_tail(&rb->list, &priv->tty_inqueue); |
|
|
|
hvc_kick(); /* wake up hvc thread */ |
|
|
|
unlock_return: |
|
spin_unlock(&priv->lock); |
|
} |
|
|
|
/** |
|
* hvc_iucv_msg_complete() - IUCV handler to process message completion |
|
* @path: Pending path (struct iucv_path) |
|
* @msg: Pointer to the IUCV message |
|
* |
|
* The function is called upon completion of message delivery to remove the |
|
* message from the outqueue. Additional delivery information can be found |
|
* msg->audit: rejected messages (0x040000 (IPADRJCT)), and |
|
* purged messages (0x010000 (IPADPGNR)). |
|
* |
|
* Locking: struct hvc_iucv_private->lock |
|
*/ |
|
static void hvc_iucv_msg_complete(struct iucv_path *path, |
|
struct iucv_message *msg) |
|
{ |
|
struct hvc_iucv_private *priv = path->private; |
|
struct iucv_tty_buffer *ent, *next; |
|
LIST_HEAD(list_remove); |
|
|
|
spin_lock(&priv->lock); |
|
list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list) |
|
if (ent->msg.id == msg->id) { |
|
list_move(&ent->list, &list_remove); |
|
break; |
|
} |
|
wake_up(&priv->sndbuf_waitq); |
|
spin_unlock(&priv->lock); |
|
destroy_tty_buffer_list(&list_remove); |
|
} |
|
|
|
static ssize_t hvc_iucv_dev_termid_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
struct hvc_iucv_private *priv = dev_get_drvdata(dev); |
|
size_t len; |
|
|
|
len = sizeof(priv->srv_name); |
|
memcpy(buf, priv->srv_name, len); |
|
EBCASC(buf, len); |
|
buf[len++] = '\n'; |
|
return len; |
|
} |
|
|
|
static ssize_t hvc_iucv_dev_state_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
struct hvc_iucv_private *priv = dev_get_drvdata(dev); |
|
return sprintf(buf, "%u:%u\n", priv->iucv_state, priv->tty_state); |
|
} |
|
|
|
static ssize_t hvc_iucv_dev_peer_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
struct hvc_iucv_private *priv = dev_get_drvdata(dev); |
|
char vmid[9], ipuser[9]; |
|
|
|
memset(vmid, 0, sizeof(vmid)); |
|
memset(ipuser, 0, sizeof(ipuser)); |
|
|
|
spin_lock_bh(&priv->lock); |
|
if (priv->iucv_state == IUCV_CONNECTED) { |
|
memcpy(vmid, priv->info_path, 8); |
|
memcpy(ipuser, priv->info_path + 8, 8); |
|
} |
|
spin_unlock_bh(&priv->lock); |
|
EBCASC(ipuser, 8); |
|
|
|
return sprintf(buf, "%s:%s\n", vmid, ipuser); |
|
} |
|
|
|
|
|
/* HVC operations */ |
|
static const struct hv_ops hvc_iucv_ops = { |
|
.get_chars = hvc_iucv_get_chars, |
|
.put_chars = hvc_iucv_put_chars, |
|
.notifier_add = hvc_iucv_notifier_add, |
|
.notifier_del = hvc_iucv_notifier_del, |
|
.notifier_hangup = hvc_iucv_notifier_hangup, |
|
.dtr_rts = hvc_iucv_dtr_rts, |
|
}; |
|
|
|
/* IUCV HVC device attributes */ |
|
static DEVICE_ATTR(termid, 0640, hvc_iucv_dev_termid_show, NULL); |
|
static DEVICE_ATTR(state, 0640, hvc_iucv_dev_state_show, NULL); |
|
static DEVICE_ATTR(peer, 0640, hvc_iucv_dev_peer_show, NULL); |
|
static struct attribute *hvc_iucv_dev_attrs[] = { |
|
&dev_attr_termid.attr, |
|
&dev_attr_state.attr, |
|
&dev_attr_peer.attr, |
|
NULL, |
|
}; |
|
static struct attribute_group hvc_iucv_dev_attr_group = { |
|
.attrs = hvc_iucv_dev_attrs, |
|
}; |
|
static const struct attribute_group *hvc_iucv_dev_attr_groups[] = { |
|
&hvc_iucv_dev_attr_group, |
|
NULL, |
|
}; |
|
|
|
|
|
/** |
|
* hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance |
|
* @id: hvc_iucv_table index |
|
* @is_console: Flag if the instance is used as Linux console |
|
* |
|
* This function allocates a new hvc_iucv_private structure and stores |
|
* the instance in hvc_iucv_table at index @id. |
|
* Returns 0 on success; otherwise non-zero. |
|
*/ |
|
static int __init hvc_iucv_alloc(int id, unsigned int is_console) |
|
{ |
|
struct hvc_iucv_private *priv; |
|
char name[9]; |
|
int rc; |
|
|
|
priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL); |
|
if (!priv) |
|
return -ENOMEM; |
|
|
|
spin_lock_init(&priv->lock); |
|
INIT_LIST_HEAD(&priv->tty_outqueue); |
|
INIT_LIST_HEAD(&priv->tty_inqueue); |
|
INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work); |
|
init_waitqueue_head(&priv->sndbuf_waitq); |
|
|
|
priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL); |
|
if (!priv->sndbuf) { |
|
kfree(priv); |
|
return -ENOMEM; |
|
} |
|
|
|
/* set console flag */ |
|
priv->is_console = is_console; |
|
|
|
/* allocate hvc device */ |
|
priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ |
|
HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); |
|
if (IS_ERR(priv->hvc)) { |
|
rc = PTR_ERR(priv->hvc); |
|
goto out_error_hvc; |
|
} |
|
|
|
/* notify HVC thread instead of using polling */ |
|
priv->hvc->irq_requested = 1; |
|
|
|
/* setup iucv related information */ |
|
snprintf(name, 9, "lnxhvc%-2d", id); |
|
memcpy(priv->srv_name, name, 8); |
|
ASCEBC(priv->srv_name, 8); |
|
|
|
/* create and setup device */ |
|
priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL); |
|
if (!priv->dev) { |
|
rc = -ENOMEM; |
|
goto out_error_dev; |
|
} |
|
dev_set_name(priv->dev, "hvc_iucv%d", id); |
|
dev_set_drvdata(priv->dev, priv); |
|
priv->dev->bus = &iucv_bus; |
|
priv->dev->parent = iucv_root; |
|
priv->dev->groups = hvc_iucv_dev_attr_groups; |
|
priv->dev->release = (void (*)(struct device *)) kfree; |
|
rc = device_register(priv->dev); |
|
if (rc) { |
|
put_device(priv->dev); |
|
goto out_error_dev; |
|
} |
|
|
|
hvc_iucv_table[id] = priv; |
|
return 0; |
|
|
|
out_error_dev: |
|
hvc_remove(priv->hvc); |
|
out_error_hvc: |
|
free_page((unsigned long) priv->sndbuf); |
|
kfree(priv); |
|
|
|
return rc; |
|
} |
|
|
|
/** |
|
* hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances |
|
*/ |
|
static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv) |
|
{ |
|
hvc_remove(priv->hvc); |
|
device_unregister(priv->dev); |
|
free_page((unsigned long) priv->sndbuf); |
|
kfree(priv); |
|
} |
|
|
|
/** |
|
* hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID |
|
* @filter: String containing a comma-separated list of z/VM user IDs |
|
* @dest: Location where to store the parsed z/VM user ID |
|
*/ |
|
static const char *hvc_iucv_parse_filter(const char *filter, char *dest) |
|
{ |
|
const char *nextdelim, *residual; |
|
size_t len; |
|
|
|
nextdelim = strchr(filter, ','); |
|
if (nextdelim) { |
|
len = nextdelim - filter; |
|
residual = nextdelim + 1; |
|
} else { |
|
len = strlen(filter); |
|
residual = filter + len; |
|
} |
|
|
|
if (len == 0) |
|
return ERR_PTR(-EINVAL); |
|
|
|
/* check for '\n' (if called from sysfs) */ |
|
if (filter[len - 1] == '\n') |
|
len--; |
|
|
|
/* prohibit filter entries containing the wildcard character only */ |
|
if (len == 1 && *filter == FILTER_WILDCARD_CHAR) |
|
return ERR_PTR(-EINVAL); |
|
|
|
if (len > 8) |
|
return ERR_PTR(-EINVAL); |
|
|
|
/* pad with blanks and save upper case version of user ID */ |
|
memset(dest, ' ', 8); |
|
while (len--) |
|
dest[len] = toupper(filter[len]); |
|
return residual; |
|
} |
|
|
|
/** |
|
* hvc_iucv_setup_filter() - Set up z/VM user ID filter |
|
* @filter: String consisting of a comma-separated list of z/VM user IDs |
|
* |
|
* The function parses the @filter string and creates an array containing |
|
* the list of z/VM user ID filter entries. |
|
* Return code 0 means success, -EINVAL if the filter is syntactically |
|
* incorrect, -ENOMEM if there was not enough memory to allocate the |
|
* filter list array, or -ENOSPC if too many z/VM user IDs have been specified. |
|
*/ |
|
static int hvc_iucv_setup_filter(const char *val) |
|
{ |
|
const char *residual; |
|
int err; |
|
size_t size, count; |
|
void *array, *old_filter; |
|
|
|
count = strlen(val); |
|
if (count == 0 || (count == 1 && val[0] == '\n')) { |
|
size = 0; |
|
array = NULL; |
|
goto out_replace_filter; /* clear filter */ |
|
} |
|
|
|
/* count user IDs in order to allocate sufficient memory */ |
|
size = 1; |
|
residual = val; |
|
while ((residual = strchr(residual, ',')) != NULL) { |
|
residual++; |
|
size++; |
|
} |
|
|
|
/* check if the specified list exceeds the filter limit */ |
|
if (size > MAX_VMID_FILTER) |
|
return -ENOSPC; |
|
|
|
array = kcalloc(size, 8, GFP_KERNEL); |
|
if (!array) |
|
return -ENOMEM; |
|
|
|
count = size; |
|
residual = val; |
|
while (*residual && count) { |
|
residual = hvc_iucv_parse_filter(residual, |
|
array + ((size - count) * 8)); |
|
if (IS_ERR(residual)) { |
|
err = PTR_ERR(residual); |
|
kfree(array); |
|
goto out_err; |
|
} |
|
count--; |
|
} |
|
|
|
out_replace_filter: |
|
write_lock_bh(&hvc_iucv_filter_lock); |
|
old_filter = hvc_iucv_filter; |
|
hvc_iucv_filter_size = size; |
|
hvc_iucv_filter = array; |
|
write_unlock_bh(&hvc_iucv_filter_lock); |
|
kfree(old_filter); |
|
|
|
err = 0; |
|
out_err: |
|
return err; |
|
} |
|
|
|
/** |
|
* param_set_vmidfilter() - Set z/VM user ID filter parameter |
|
* @val: String consisting of a comma-separated list of z/VM user IDs |
|
* @kp: Kernel parameter pointing to hvc_iucv_filter array |
|
* |
|
* The function sets up the z/VM user ID filter specified as comma-separated |
|
* list of user IDs in @val. |
|
* Note: If it is called early in the boot process, @val is stored and |
|
* parsed later in hvc_iucv_init(). |
|
*/ |
|
static int param_set_vmidfilter(const char *val, const struct kernel_param *kp) |
|
{ |
|
int rc; |
|
|
|
if (!MACHINE_IS_VM || !hvc_iucv_devices) |
|
return -ENODEV; |
|
|
|
if (!val) |
|
return -EINVAL; |
|
|
|
rc = 0; |
|
if (slab_is_available()) |
|
rc = hvc_iucv_setup_filter(val); |
|
else |
|
hvc_iucv_filter_string = val; /* defer... */ |
|
return rc; |
|
} |
|
|
|
/** |
|
* param_get_vmidfilter() - Get z/VM user ID filter |
|
* @buffer: Buffer to store z/VM user ID filter, |
|
* (buffer size assumption PAGE_SIZE) |
|
* @kp: Kernel parameter pointing to the hvc_iucv_filter array |
|
* |
|
* The function stores the filter as a comma-separated list of z/VM user IDs |
|
* in @buffer. Typically, sysfs routines call this function for attr show. |
|
*/ |
|
static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp) |
|
{ |
|
int rc; |
|
size_t index, len; |
|
void *start, *end; |
|
|
|
if (!MACHINE_IS_VM || !hvc_iucv_devices) |
|
return -ENODEV; |
|
|
|
rc = 0; |
|
read_lock_bh(&hvc_iucv_filter_lock); |
|
for (index = 0; index < hvc_iucv_filter_size; index++) { |
|
start = hvc_iucv_filter + (8 * index); |
|
end = memchr(start, ' ', 8); |
|
len = (end) ? end - start : 8; |
|
memcpy(buffer + rc, start, len); |
|
rc += len; |
|
buffer[rc++] = ','; |
|
} |
|
read_unlock_bh(&hvc_iucv_filter_lock); |
|
if (rc) |
|
buffer[--rc] = '\0'; /* replace last comma and update rc */ |
|
return rc; |
|
} |
|
|
|
#define param_check_vmidfilter(name, p) __param_check(name, p, void) |
|
|
|
static const struct kernel_param_ops param_ops_vmidfilter = { |
|
.set = param_set_vmidfilter, |
|
.get = param_get_vmidfilter, |
|
}; |
|
|
|
/** |
|
* hvc_iucv_init() - z/VM IUCV HVC device driver initialization |
|
*/ |
|
static int __init hvc_iucv_init(void) |
|
{ |
|
int rc; |
|
unsigned int i; |
|
|
|
if (!hvc_iucv_devices) |
|
return -ENODEV; |
|
|
|
if (!MACHINE_IS_VM) { |
|
pr_notice("The z/VM IUCV HVC device driver cannot " |
|
"be used without z/VM\n"); |
|
rc = -ENODEV; |
|
goto out_error; |
|
} |
|
|
|
if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) { |
|
pr_err("%lu is not a valid value for the hvc_iucv= " |
|
"kernel parameter\n", hvc_iucv_devices); |
|
rc = -EINVAL; |
|
goto out_error; |
|
} |
|
|
|
/* parse hvc_iucv_allow string and create z/VM user ID filter list */ |
|
if (hvc_iucv_filter_string) { |
|
rc = hvc_iucv_setup_filter(hvc_iucv_filter_string); |
|
switch (rc) { |
|
case 0: |
|
break; |
|
case -ENOMEM: |
|
pr_err("Allocating memory failed with " |
|
"reason code=%d\n", 3); |
|
goto out_error; |
|
case -EINVAL: |
|
pr_err("hvc_iucv_allow= does not specify a valid " |
|
"z/VM user ID list\n"); |
|
goto out_error; |
|
case -ENOSPC: |
|
pr_err("hvc_iucv_allow= specifies too many " |
|
"z/VM user IDs\n"); |
|
goto out_error; |
|
default: |
|
goto out_error; |
|
} |
|
} |
|
|
|
hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT, |
|
sizeof(struct iucv_tty_buffer), |
|
0, 0, NULL); |
|
if (!hvc_iucv_buffer_cache) { |
|
pr_err("Allocating memory failed with reason code=%d\n", 1); |
|
rc = -ENOMEM; |
|
goto out_error; |
|
} |
|
|
|
hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR, |
|
hvc_iucv_buffer_cache); |
|
if (!hvc_iucv_mempool) { |
|
pr_err("Allocating memory failed with reason code=%d\n", 2); |
|
kmem_cache_destroy(hvc_iucv_buffer_cache); |
|
rc = -ENOMEM; |
|
goto out_error; |
|
} |
|
|
|
/* register the first terminal device as console |
|
* (must be done before allocating hvc terminal devices) */ |
|
rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops); |
|
if (rc) { |
|
pr_err("Registering HVC terminal device as " |
|
"Linux console failed\n"); |
|
goto out_error_memory; |
|
} |
|
|
|
/* allocate hvc_iucv_private structs */ |
|
for (i = 0; i < hvc_iucv_devices; i++) { |
|
rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0); |
|
if (rc) { |
|
pr_err("Creating a new HVC terminal device " |
|
"failed with error code=%d\n", rc); |
|
goto out_error_hvc; |
|
} |
|
} |
|
|
|
/* register IUCV callback handler */ |
|
rc = iucv_register(&hvc_iucv_handler, 0); |
|
if (rc) { |
|
pr_err("Registering IUCV handlers failed with error code=%d\n", |
|
rc); |
|
goto out_error_hvc; |
|
} |
|
|
|
return 0; |
|
|
|
out_error_hvc: |
|
for (i = 0; i < hvc_iucv_devices; i++) |
|
if (hvc_iucv_table[i]) |
|
hvc_iucv_destroy(hvc_iucv_table[i]); |
|
out_error_memory: |
|
mempool_destroy(hvc_iucv_mempool); |
|
kmem_cache_destroy(hvc_iucv_buffer_cache); |
|
out_error: |
|
kfree(hvc_iucv_filter); |
|
hvc_iucv_devices = 0; /* ensure that we do not provide any device */ |
|
return rc; |
|
} |
|
|
|
/** |
|
* hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter |
|
* @val: Parameter value (numeric) |
|
*/ |
|
static int __init hvc_iucv_config(char *val) |
|
{ |
|
return kstrtoul(val, 10, &hvc_iucv_devices); |
|
} |
|
|
|
|
|
device_initcall(hvc_iucv_init); |
|
__setup("hvc_iucv=", hvc_iucv_config); |
|
core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640);
|
|
|