From d79a580936396bbcd2f4fae2c6215f9cf81e3c0d Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:43:52 -0800 Subject: [PATCH] uml: console locking fixes Clean up the console driver locking. There are various problems here, including sleeping under a spinlock and spinlock recursion, some of which are fixed here. This patch deals with the locking involved with opens and closes. The problem is that an mconsole request to change a console's configuration can race with an open. Changing a configuration should only be done when a console isn't opened. Also, an open must be looking at a stable configuration. In addition, a get configuration request must observe the same locking since it must also see a stable configuration. With the old locking, it was possible for this to hang indefinitely in some cases because open would block for a long time waiting for a connection from the host while holding the lock needed by the mconsole request. As explained in the long comment, this is fixed by adding a spinlock for the use count and configuration and a mutex for the actual open and close. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/stdio_console.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index 7a4897e27f42..9b2dd0b8a43b 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -83,9 +83,9 @@ static struct lines console_lines = LINES_INIT(MAX_TTYS); /* The array is initialized by line_init, which is an initcall. The * individual elements are protected by individual semaphores. */ -struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver), - [ 1 ... MAX_TTYS - 1 ] = - LINE_INIT(CONFIG_CON_CHAN, &driver) }; +static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver), + [ 1 ... MAX_TTYS - 1 ] = + LINE_INIT(CONFIG_CON_CHAN, &driver) }; static int con_config(char *str) { -- cgit v1.2.3 From f28169d2000177e8b72ccc6d72887be779dceca8 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:43:53 -0800 Subject: [PATCH] uml: return hotplug errors to host I noticed that errors happening while hotplugging devices from the host were never returned back to the mconsole client. In some cases, success was returned instead of even an information-free error. This patch cleans that up by having the low-level configuration code pass back an error string along with an error code. At the top level, which knows whether it is early boot time or responding to an mconsole request, the string is printk'd or returned to the mconsole client. There are also whitespace and trivial code cleanups in the surrounding code. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/chan_kern.c | 77 +++++++---------------- arch/um/drivers/line.c | 66 ++++++++++++-------- arch/um/drivers/mconsole_kern.c | 40 ++++++++---- arch/um/drivers/net_kern.c | 97 ++++++++++++++--------------- arch/um/drivers/ssl.c | 24 +++++--- arch/um/drivers/stdio_console.c | 22 ++++--- arch/um/drivers/ubd_kern.c | 132 ++++++++++++++++++++++------------------ arch/um/include/chan_kern.h | 2 +- arch/um/include/line.h | 8 ++- arch/um/include/mconsole_kern.h | 15 +---- arch/um/kernel/tt/gdb.c | 4 +- arch/um/kernel/tt/gdb_kern.c | 4 +- 12 files changed, 253 insertions(+), 238 deletions(-) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c index 7d4190e55654..4e7e3cfa21f9 100644 --- a/arch/um/drivers/chan_kern.c +++ b/arch/um/drivers/chan_kern.c @@ -19,44 +19,11 @@ #include "line.h" #include "os.h" -/* XXX: could well be moved to somewhere else, if needed. */ -static int my_printf(const char * fmt, ...) - __attribute__ ((format (printf, 1, 2))); - -static int my_printf(const char * fmt, ...) -{ - /* Yes, can be called on atomic context.*/ - char *buf = kmalloc(4096, GFP_ATOMIC); - va_list args; - int r; - - if (!buf) { - /* We print directly fmt. - * Yes, yes, yes, feel free to complain. */ - r = strlen(fmt); - } else { - va_start(args, fmt); - r = vsprintf(buf, fmt, args); - va_end(args); - fmt = buf; - } - - if (r) - r = os_write_file(1, fmt, r); - return r; - -} - #ifdef CONFIG_NOCONFIG_CHAN -/* Despite its name, there's no added trailing newline. */ -static int my_puts(const char * buf) +static void *not_configged_init(char *str, int device, + const struct chan_opts *opts) { - return os_write_file(1, buf, strlen(buf)); -} - -static void *not_configged_init(char *str, int device, struct chan_opts *opts) -{ - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return NULL; } @@ -64,34 +31,34 @@ static void *not_configged_init(char *str, int device, struct chan_opts *opts) static int not_configged_open(int input, int output, int primary, void *data, char **dev_out) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_close(int fd, void *data) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); } static int not_configged_read(int fd, char *c_out, void *data) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return -EIO; } static int not_configged_write(int fd, const char *buf, int len, void *data) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return -EIO; } static int not_configged_console_write(int fd, const char *buf, int len) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return -EIO; } @@ -99,14 +66,14 @@ static int not_configged_console_write(int fd, const char *buf, int len) static int not_configged_window_size(int fd, void *data, unsigned short *rows, unsigned short *cols) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_free(void *data) { - my_puts("Using a channel type which is configured out of " + printk("Using a channel type which is configured out of " "UML\n"); } @@ -534,7 +501,7 @@ static const struct chan_type chan_table[] = { }; static struct chan *parse_chan(struct line *line, char *str, int device, - const struct chan_opts *opts) + const struct chan_opts *opts, char **error_out) { const struct chan_type *entry; const struct chan_ops *ops; @@ -553,19 +520,21 @@ static struct chan *parse_chan(struct line *line, char *str, int device, } } if(ops == NULL){ - my_printf("parse_chan couldn't parse \"%s\"\n", - str); + *error_out = "No match for configured backends"; return NULL; } - if(ops->init == NULL) - return NULL; + data = (*ops->init)(str, device, opts); - if(data == NULL) + if(data == NULL){ + *error_out = "Configuration failed"; return NULL; + } chan = kmalloc(sizeof(*chan), GFP_ATOMIC); - if(chan == NULL) + if(chan == NULL){ + *error_out = "Memory allocation failed"; return NULL; + } *chan = ((struct chan) { .list = LIST_HEAD_INIT(chan->list), .free_list = LIST_HEAD_INIT(chan->free_list), @@ -582,7 +551,7 @@ static struct chan *parse_chan(struct line *line, char *str, int device, } int parse_chan_pair(char *str, struct line *line, int device, - const struct chan_opts *opts) + const struct chan_opts *opts, char **error_out) { struct list_head *chans = &line->chan_list; struct chan *new, *chan; @@ -599,14 +568,14 @@ int parse_chan_pair(char *str, struct line *line, int device, in = str; *out = '\0'; out++; - new = parse_chan(line, in, device, opts); + new = parse_chan(line, in, device, opts, error_out); if(new == NULL) return -1; new->input = 1; list_add(&new->list, chans); - new = parse_chan(line, out, device, opts); + new = parse_chan(line, out, device, opts, error_out); if(new == NULL) return -1; @@ -614,7 +583,7 @@ int parse_chan_pair(char *str, struct line *line, int device, new->output = 1; } else { - new = parse_chan(line, str, device, opts); + new = parse_chan(line, str, device, opts, error_out); if(new == NULL) return -1; diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c index 799fca3644e9..e620ed46ed3f 100644 --- a/arch/um/drivers/line.c +++ b/arch/um/drivers/line.c @@ -549,14 +549,16 @@ void close_lines(struct line *lines, int nlines) close_chan(&lines[i].chan_list, 0); } -static void setup_one_line(struct line *lines, int n, char *init, int init_prio) +static int setup_one_line(struct line *lines, int n, char *init, int init_prio, + char **error_out) { struct line *line = &lines[n]; + int err = -EINVAL; spin_lock(&line->count_lock); if(line->tty != NULL){ - printk("line_setup - device %d is open\n", n); + *error_out = "Device is already open"; goto out; } @@ -569,18 +571,22 @@ static void setup_one_line(struct line *lines, int n, char *init, int init_prio) line->valid = 1; } } + err = 0; out: spin_unlock(&line->count_lock); + return err; } /* Common setup code for both startup command line and mconsole initialization. * @lines contains the array (of size @num) to modify; * @init is the setup string; + * @error_out is an error string in the case of failure; */ -int line_setup(struct line *lines, unsigned int num, char *init) +int line_setup(struct line *lines, unsigned int num, char *init, + char **error_out) { - int i, n; + int i, n, err; char *end; if(*init == '=') { @@ -591,52 +597,56 @@ int line_setup(struct line *lines, unsigned int num, char *init) else { n = simple_strtoul(init, &end, 0); if(*end != '='){ - printk(KERN_ERR "line_setup failed to parse \"%s\"\n", - init); - return 0; + *error_out = "Couldn't parse device number"; + return -EINVAL; } init = end; } init++; if (n >= (signed int) num) { - printk("line_setup - %d out of range ((0 ... %d) allowed)\n", - n, num - 1); - return 0; + *error_out = "Device number out of range"; + return -EINVAL; + } + else if (n >= 0){ + err = setup_one_line(lines, n, init, INIT_ONE, error_out); + if(err) + return err; } - else if (n >= 0) - setup_one_line(lines, n, init, INIT_ONE); else { - for(i = 0; i < num; i++) - setup_one_line(lines, i, init, INIT_ALL); + for(i = 0; i < num; i++){ + err = setup_one_line(lines, i, init, INIT_ALL, + error_out); + if(err) + return err; + } } return n == -1 ? num : n; } int line_config(struct line *lines, unsigned int num, char *str, - const struct chan_opts *opts) + const struct chan_opts *opts, char **error_out) { struct line *line; char *new; int n; if(*str == '='){ - printk("line_config - can't configure all devices from " - "mconsole\n"); - return 1; + *error_out = "Can't configure all devices from mconsole"; + return -EINVAL; } new = kstrdup(str, GFP_KERNEL); if(new == NULL){ - printk("line_config - kstrdup failed\n"); - return 1; + *error_out = "Failed to allocate memory"; + return -ENOMEM; } - n = line_setup(lines, num, new); + n = line_setup(lines, num, new, error_out); if(n < 0) - return 1; + return n; line = &lines[n]; - return parse_chan_pair(line->init_str, line, n, opts); + return parse_chan_pair(line->init_str, line, n, opts, error_out); } int line_get_config(char *name, struct line *lines, unsigned int num, char *str, @@ -685,13 +695,13 @@ int line_id(char **str, int *start_out, int *end_out) return n; } -int line_remove(struct line *lines, unsigned int num, int n) +int line_remove(struct line *lines, unsigned int num, int n, char **error_out) { int err; char config[sizeof("conxxxx=none\0")]; sprintf(config, "%d=none", n); - err = line_setup(lines, num, config); + err = line_setup(lines, num, config, error_out); if(err >= 0) err = 0; return err; @@ -740,6 +750,7 @@ static LIST_HEAD(winch_handlers); void lines_init(struct line *lines, int nlines, struct chan_opts *opts) { struct line *line; + char *error; int i; for(i = 0; i < nlines; i++){ @@ -754,8 +765,9 @@ void lines_init(struct line *lines, int nlines, struct chan_opts *opts) if(line->init_str == NULL) printk("lines_init - kstrdup returned NULL\n"); - if(parse_chan_pair(line->init_str, line, i, opts)){ - printk("parse_chan_pair failed for device %d\n", i); + if(parse_chan_pair(line->init_str, line, i, opts, &error)){ + printk("parse_chan_pair failed for device %d : %s\n", + i, error); line->valid = 0; } } diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index 96f0189327af..832d5c766ca8 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -371,14 +371,16 @@ static unsigned long long unplugged_pages_count = 0; static struct list_head unplugged_pages = LIST_HEAD_INIT(unplugged_pages); static int unplug_index = UNPLUGGED_PER_PAGE; -static int mem_config(char *str) +static int mem_config(char *str, char **error_out) { unsigned long long diff; int err = -EINVAL, i, add; char *ret; - if(str[0] != '=') + if(str[0] != '='){ + *error_out = "Expected '=' after 'mem'"; goto out; + } str++; if(str[0] == '-') @@ -386,12 +388,17 @@ static int mem_config(char *str) else if(str[0] == '+'){ add = 1; } - else goto out; + else { + *error_out = "Expected increment to start with '-' or '+'"; + goto out; + } str++; diff = memparse(str, &ret); - if(*ret != '\0') + if(*ret != '\0'){ + *error_out = "Failed to parse memory increment"; goto out; + } diff /= PAGE_SIZE; @@ -435,11 +442,14 @@ static int mem_config(char *str) unplugged = list_entry(entry, struct unplugged_pages, list); - unplugged->pages[unplug_index++] = addr; err = os_drop_memory(addr, PAGE_SIZE); - if(err) + if(err){ printk("Failed to release memory - " "errno = %d\n", err); + *error_out = "Failed to release memory"; + goto out; + } + unplugged->pages[unplug_index++] = addr; } unplugged_pages_count++; @@ -470,8 +480,9 @@ static int mem_id(char **str, int *start_out, int *end_out) return 0; } -static int mem_remove(int n) +static int mem_remove(int n, char **error_out) { + *error_out = "Memory doesn't support the remove operation"; return -EBUSY; } @@ -542,7 +553,7 @@ static void mconsole_get_config(int (*get_config)(char *, char *, int, void mconsole_config(struct mc_request *req) { struct mc_device *dev; - char *ptr = req->request.data, *name; + char *ptr = req->request.data, *name, *error_string = ""; int err; ptr += strlen("config"); @@ -559,8 +570,8 @@ void mconsole_config(struct mc_request *req) ptr++; if(*ptr == '='){ - err = (*dev->config)(name); - mconsole_reply(req, "", err, 0); + err = (*dev->config)(name, &error_string); + mconsole_reply(req, error_string, err, 0); } else mconsole_get_config(dev->get_config, req, name); } @@ -595,13 +606,16 @@ void mconsole_remove(struct mc_request *req) goto out; } - err = (*dev->remove)(n); + err_msg = NULL; + err = (*dev->remove)(n, &err_msg); switch(err){ case -ENODEV: - err_msg = "Device doesn't exist"; + if(err_msg == NULL) + err_msg = "Device doesn't exist"; break; case -EBUSY: - err_msg = "Device is currently open"; + if(err_msg == NULL) + err_msg = "Device is currently open"; break; default: break; diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c index afe3d427ddfa..07e839e387db 100644 --- a/arch/um/drivers/net_kern.c +++ b/arch/um/drivers/net_kern.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and + * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and * James Leu (jleu@mindspring.net). * Copyright (C) 2001 by various other people who didn't put their name here. * Licensed under the GPL. @@ -91,8 +91,8 @@ irqreturn_t uml_net_interrupt(int irq, void *dev_id) spin_lock(&lp->lock); while((err = uml_net_rx(dev)) > 0) ; if(err < 0) { - printk(KERN_ERR - "Device '%s' read returned %d, shutting it down\n", + printk(KERN_ERR + "Device '%s' read returned %d, shutting it down\n", dev->name, err); /* dev_close can't be called in interrupt context, and takes * again lp->lock. @@ -159,7 +159,7 @@ out: static int uml_net_close(struct net_device *dev) { struct uml_net_private *lp = dev->priv; - + netif_stop_queue(dev); free_irq(dev->irq, dev); @@ -194,7 +194,7 @@ static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev) /* this is normally done in the interrupt when tx finishes */ netif_wake_queue(dev); - } + } else if(len == 0){ netif_start_queue(dev); lp->stats.tx_dropped++; @@ -333,7 +333,7 @@ static int eth_configure(int n, void *init, char *mac, struct uml_net_private *lp; int save, err, size; - size = transport->private_size + sizeof(struct uml_net_private) + + size = transport->private_size + sizeof(struct uml_net_private) + sizeof(((struct uml_net_private *) 0)->user); device = kzalloc(sizeof(*device), GFP_KERNEL); @@ -438,7 +438,7 @@ static int eth_configure(int n, void *init, char *mac, lp->tl.function = uml_net_user_timer_expire; memcpy(lp->mac, device->mac, sizeof(lp->mac)); - if (transport->user->init) + if (transport->user->init) (*transport->user->init)(&lp->user, dev); set_ether_mac(dev, device->mac); @@ -463,35 +463,33 @@ static struct uml_net *find_device(int n) return(device); } -static int eth_parse(char *str, int *index_out, char **str_out) +static int eth_parse(char *str, int *index_out, char **str_out, + char **error_out) { char *end; - int n; + int n, err = -EINVAL;; n = simple_strtoul(str, &end, 0); if(end == str){ - printk(KERN_ERR "eth_setup: Failed to parse '%s'\n", str); - return(1); - } - if(n < 0){ - printk(KERN_ERR "eth_setup: device %d is negative\n", n); - return(1); + *error_out = "Bad device number"; + return err; } + str = end; if(*str != '='){ - printk(KERN_ERR - "eth_setup: expected '=' after device number\n"); - return(1); + *error_out = "Expected '=' after device number"; + return err; } + str++; if(find_device(n)){ - printk(KERN_ERR "eth_setup: Device %d already configured\n", - n); - return(1); + *error_out = "Device already configured"; + return err; } - if(index_out) *index_out = n; + + *index_out = n; *str_out = str; - return(0); + return 0; } struct eth_init { @@ -581,11 +579,15 @@ static int eth_setup_common(char *str, int index) static int eth_setup(char *str) { struct eth_init *new; + char *error; int n, err; - err = eth_parse(str, &n, &str); - if(err) + err = eth_parse(str, &n, &str, &error); + if(err){ + printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n", + str, error); return 1; + } new = alloc_bootmem(sizeof(*new)); if (new == NULL){ @@ -619,26 +621,30 @@ static int eth_init(void) if(eth_setup_common(eth->init, eth->index)) list_del(ð->list); } - + return(1); } __initcall(eth_init); #endif -static int net_config(char *str) +static int net_config(char *str, char **error_out) { int n, err; - err = eth_parse(str, &n, &str); - if(err) return(err); + err = eth_parse(str, &n, &str, error_out); + if(err) + return err; + /* This string is broken up and the pieces used by the underlying + * driver. So, it is freed only if eth_setup_common fails. + */ str = kstrdup(str, GFP_KERNEL); if(str == NULL){ - printk(KERN_ERR "net_config failed to strdup string\n"); - return(-1); + *error_out = "net_config failed to strdup string"; + return -ENOMEM; } err = !eth_setup_common(str, n); - if(err) + if(err) kfree(str); return(err); } @@ -658,7 +664,7 @@ static int net_id(char **str, int *start_out, int *end_out) return n; } -static int net_remove(int n) +static int net_remove(int n, char **error_out) { struct uml_net *device; struct net_device *dev; @@ -727,7 +733,7 @@ struct notifier_block uml_inetaddr_notifier = { static int uml_net_init(void) { struct list_head *ele; - struct uml_net_private *lp; + struct uml_net_private *lp; struct in_device *ip; struct in_ifaddr *in; @@ -747,7 +753,7 @@ static int uml_net_init(void) uml_inetaddr_event(NULL, NETDEV_UP, in); in = in->ifa_next; } - } + } return(0); } @@ -783,8 +789,8 @@ struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra) return(skb); } -void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *, - void *), +void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *, + void *), void *arg) { struct net_device *dev = d; @@ -809,11 +815,11 @@ int dev_netmask(void *d, void *m) struct in_ifaddr *in; __be32 *mask_out = m; - if(ip == NULL) + if(ip == NULL) return(1); in = ip->ifa_list; - if(in == NULL) + if(in == NULL) return(1); *mask_out = in->ifa_mask; @@ -835,7 +841,7 @@ void free_output_buffer(void *buffer) free_pages((unsigned long) buffer, 0); } -int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out, +int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out, char **gate_addr) { char *remain; @@ -854,14 +860,3 @@ unsigned short eth_protocol(struct sk_buff *skb) { return(eth_type_trans(skb, skb->dev)); } - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c index ed9c59082d0d..1e82430b8444 100644 --- a/arch/um/drivers/ssl.c +++ b/arch/um/drivers/ssl.c @@ -46,9 +46,9 @@ static struct chan_opts opts = { .in_kernel = 1, }; -static int ssl_config(char *str); +static int ssl_config(char *str, char **error_out); static int ssl_get_config(char *dev, char *str, int size, char **error_out); -static int ssl_remove(int n); +static int ssl_remove(int n, char **error_out); static struct line_driver driver = { .name = "UML serial line", @@ -80,9 +80,10 @@ static struct line serial_lines[NR_PORTS] = static struct lines lines = LINES_INIT(NR_PORTS); -static int ssl_config(char *str) +static int ssl_config(char *str, char **error_out) { - return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts); + return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts, + error_out); } static int ssl_get_config(char *dev, char *str, int size, char **error_out) @@ -91,9 +92,10 @@ static int ssl_get_config(char *dev, char *str, int size, char **error_out) size, error_out); } -static int ssl_remove(int n) +static int ssl_remove(int n, char **error_out) { - return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n); + return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n, + error_out); } static int ssl_open(struct tty_struct *tty, struct file *filp) @@ -212,7 +214,15 @@ __uml_exitcall(ssl_exit); static int ssl_chan_setup(char *str) { - return line_setup(serial_lines, ARRAY_SIZE(serial_lines), str); + char *error; + int ret; + + ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error); + if(ret < 0) + printk(KERN_ERR "Failed to set up serial line with " + "configuration string \"%s\" : %s\n", str, error); + + return 1; } __setup("ssl", ssl_chan_setup); diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index 9b2dd0b8a43b..3cbfe3a88607 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -52,9 +52,9 @@ static struct chan_opts opts = { .in_kernel = 1, }; -static int con_config(char *str); +static int con_config(char *str, char **error_out); static int con_get_config(char *dev, char *str, int size, char **error_out); -static int con_remove(int n); +static int con_remove(int n, char **con_remove); static struct line_driver driver = { .name = "UML console", @@ -87,9 +87,9 @@ static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver), [ 1 ... MAX_TTYS - 1 ] = LINE_INIT(CONFIG_CON_CHAN, &driver) }; -static int con_config(char *str) +static int con_config(char *str, char **error_out) { - return line_config(vts, ARRAY_SIZE(vts), str, &opts); + return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out); } static int con_get_config(char *dev, char *str, int size, char **error_out) @@ -97,9 +97,9 @@ static int con_get_config(char *dev, char *str, int size, char **error_out) return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out); } -static int con_remove(int n) +static int con_remove(int n, char **error_out) { - return line_remove(vts, ARRAY_SIZE(vts), n); + return line_remove(vts, ARRAY_SIZE(vts), n, error_out); } static int con_open(struct tty_struct *tty, struct file *filp) @@ -192,7 +192,15 @@ __uml_exitcall(console_exit); static int console_chan_setup(char *str) { - return line_setup(vts, ARRAY_SIZE(vts), str); + char *error; + int ret; + + ret = line_setup(vts, ARRAY_SIZE(vts), str, &error); + if(ret < 0) + printk(KERN_ERR "Failed to set up console with " + "configuration string \"%s\" : %s\n", str, error); + + return 1; } __setup("con", console_chan_setup); __channel_help(console_chan_setup, "con"); diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c index 49c047b75cc5..f4db97efc014 100644 --- a/arch/um/drivers/ubd_kern.c +++ b/arch/um/drivers/ubd_kern.c @@ -286,7 +286,7 @@ static int parse_unit(char **ptr) * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it * should not be freed on exit. */ -static int ubd_setup_common(char *str, int *index_out) +static int ubd_setup_common(char *str, int *index_out, char **error_out) { struct ubd *ubd_dev; struct openflags flags = global_openflags; @@ -302,56 +302,54 @@ static int ubd_setup_common(char *str, int *index_out) str++; if(!strcmp(str, "sync")){ global_openflags = of_sync(global_openflags); - return(0); + return 0; } major = simple_strtoul(str, &end, 0); if((*end != '\0') || (end == str)){ - printk(KERN_ERR - "ubd_setup : didn't parse major number\n"); - return(1); + *error_out = "Didn't parse major number"; + return -EINVAL; } - err = 1; - mutex_lock(&ubd_lock); - if(fake_major != MAJOR_NR){ - printk(KERN_ERR "Can't assign a fake major twice\n"); - goto out1; - } + err = -EINVAL; + mutex_lock(&ubd_lock); + if(fake_major != MAJOR_NR){ + *error_out = "Can't assign a fake major twice"; + goto out1; + } - fake_major = major; + fake_major = major; printk(KERN_INFO "Setting extra ubd major number to %d\n", major); - err = 0; - out1: - mutex_unlock(&ubd_lock); - return(err); + err = 0; + out1: + mutex_unlock(&ubd_lock); + return err; } n = parse_unit(&str); if(n < 0){ - printk(KERN_ERR "ubd_setup : couldn't parse unit number " - "'%s'\n", str); - return(1); + *error_out = "Couldn't parse device number"; + return -EINVAL; } if(n >= MAX_DEV){ - printk(KERN_ERR "ubd_setup : index %d out of range " - "(%d devices, from 0 to %d)\n", n, MAX_DEV, MAX_DEV - 1); - return(1); + *error_out = "Device number out of range"; + return 1; } - err = 1; + err = -EBUSY; mutex_lock(&ubd_lock); ubd_dev = &ubd_devs[n]; if(ubd_dev->file != NULL){ - printk(KERN_ERR "ubd_setup : device already configured\n"); + *error_out = "Device is already configured"; goto out; } if (index_out) *index_out = n; + err = -EINVAL; for (i = 0; i < sizeof("rscd="); i++) { switch (*str) { case 'r': @@ -370,47 +368,54 @@ static int ubd_setup_common(char *str, int *index_out) str++; goto break_loop; default: - printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r, s, c, or d)\n"); + *error_out = "Expected '=' or flag letter " + "(r, s, c, or d)"; goto out; } str++; } - if (*str == '=') - printk(KERN_ERR "ubd_setup : Too many flags specified\n"); - else - printk(KERN_ERR "ubd_setup : Expected '='\n"); + if (*str == '=') + *error_out = "Too many flags specified"; + else + *error_out = "Missing '='"; goto out; break_loop: - err = 0; backing_file = strchr(str, ','); - if (!backing_file) { + if (backing_file == NULL) backing_file = strchr(str, ':'); - } - if(backing_file){ - if(ubd_dev->no_cow) - printk(KERN_ERR "Can't specify both 'd' and a " - "cow file\n"); + if(backing_file != NULL){ + if(ubd_dev->no_cow){ + *error_out = "Can't specify both 'd' and a cow file"; + goto out; + } else { *backing_file = '\0'; backing_file++; } } + err = 0; ubd_dev->file = str; ubd_dev->cow.file = backing_file; ubd_dev->boot_openflags = flags; out: mutex_unlock(&ubd_lock); - return(err); + return err; } static int ubd_setup(char *str) { - ubd_setup_common(str, NULL); - return(1); + char *error; + int err; + + err = ubd_setup_common(str, NULL, &error); + if(err) + printk(KERN_ERR "Failed to initialize device with \"%s\" : " + "%s\n", str, error); + return 1; } __setup("ubd", ubd_setup); @@ -422,7 +427,7 @@ __uml_help(ubd_setup, " use either a ':' or a ',': the first one allows writing things like;\n" " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" " while with a ',' the shell would not expand the 2nd '~'.\n" -" When using only one filename, UML will detect whether to thread it like\n" +" When using only one filename, UML will detect whether to treat it like\n" " a COW file or a backing file. To override this detection, add the 'd'\n" " flag:\n" " ubd0d=BackingFile\n" @@ -668,18 +673,19 @@ static int ubd_disk_register(int major, u64 size, int unit, #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) -static int ubd_add(int n) +static int ubd_add(int n, char **error_out) { struct ubd *ubd_dev = &ubd_devs[n]; - int err; + int err = 0; - err = -ENODEV; if(ubd_dev->file == NULL) goto out; err = ubd_file_size(ubd_dev, &ubd_dev->size); - if(err < 0) + if(err < 0){ + *error_out = "Couldn't determine size of device's file"; goto out; + } ubd_dev->size = ROUND_BLOCK(ubd_dev->size); @@ -701,28 +707,31 @@ out: return err; } -static int ubd_config(char *str) +static int ubd_config(char *str, char **error_out) { int n, ret; + /* This string is possibly broken up and stored, so it's only + * freed if ubd_setup_common fails, or if only general options + * were set. + */ str = kstrdup(str, GFP_KERNEL); if (str == NULL) { - printk(KERN_ERR "ubd_config failed to strdup string\n"); - ret = 1; - goto out; + *error_out = "Failed to allocate memory"; + return -ENOMEM; } - ret = ubd_setup_common(str, &n); - if (ret) { - ret = -1; + + ret = ubd_setup_common(str, &n, error_out); + if (ret) goto err_free; - } + if (n == -1) { ret = 0; goto err_free; } mutex_lock(&ubd_lock); - ret = ubd_add(n); + ret = ubd_add(n, error_out); if (ret) ubd_devs[n].file = NULL; mutex_unlock(&ubd_lock); @@ -777,7 +786,7 @@ static int ubd_id(char **str, int *start_out, int *end_out) return n; } -static int ubd_remove(int n) +static int ubd_remove(int n, char **error_out) { struct ubd *ubd_dev; int err = -ENODEV; @@ -815,7 +824,9 @@ out: return err; } -/* All these are called by mconsole in process context and without ubd-specific locks. */ +/* All these are called by mconsole in process context and without + * ubd-specific locks. + */ static struct mc_device ubd_mc = { .name = "ubd", .config = ubd_config, @@ -851,7 +862,8 @@ static struct platform_driver ubd_driver = { static int __init ubd_init(void) { - int i; + char *error; + int i, err; if (register_blkdev(MAJOR_NR, "ubd")) return -1; @@ -870,8 +882,12 @@ static int __init ubd_init(void) return -1; } platform_driver_register(&ubd_driver); - for (i = 0; i < MAX_DEV; i++) - ubd_add(i); + for (i = 0; i < MAX_DEV; i++){ + err = ubd_add(i, &error); + if(err) + printk(KERN_ERR "Failed to initialize ubd device %d :" + "%s\n", i, error); + } return 0; } diff --git a/arch/um/include/chan_kern.h b/arch/um/include/chan_kern.h index 9003a343e148..2d9aa7ef4c27 100644 --- a/arch/um/include/chan_kern.h +++ b/arch/um/include/chan_kern.h @@ -30,7 +30,7 @@ struct chan { extern void chan_interrupt(struct list_head *chans, struct delayed_work *task, struct tty_struct *tty, int irq); extern int parse_chan_pair(char *str, struct line *line, int device, - const struct chan_opts *opts); + const struct chan_opts *opts, char **error_out); extern int open_chan(struct list_head *chans); extern int write_chan(struct list_head *chans, const char *buf, int len, int write_irq); diff --git a/arch/um/include/line.h b/arch/um/include/line.h index b79643eeee08..a2486b4cc9fe 100644 --- a/arch/um/include/line.h +++ b/arch/um/include/line.h @@ -76,7 +76,7 @@ struct lines { extern void line_close(struct tty_struct *tty, struct file * filp); extern int line_open(struct line *lines, struct tty_struct *tty); extern int line_setup(struct line *lines, unsigned int sizeof_lines, - char *init); + char *init, char **error_out); extern int line_write(struct tty_struct *tty, const unsigned char *buf, int len); extern void line_put_char(struct tty_struct *tty, unsigned char ch); @@ -102,9 +102,11 @@ extern void lines_init(struct line *lines, int nlines, struct chan_opts *opts); extern void close_lines(struct line *lines, int nlines); extern int line_config(struct line *lines, unsigned int sizeof_lines, - char *str, const struct chan_opts *opts); + char *str, const struct chan_opts *opts, + char **error_out); extern int line_id(char **str, int *start_out, int *end_out); -extern int line_remove(struct line *lines, unsigned int sizeof_lines, int n); +extern int line_remove(struct line *lines, unsigned int sizeof_lines, int n, + char **error_out); extern int line_get_config(char *dev, struct line *lines, unsigned int sizeof_lines, char *str, int size, char **error_out); diff --git a/arch/um/include/mconsole_kern.h b/arch/um/include/mconsole_kern.h index 1ea6d928e1cd..73030e52b2ce 100644 --- a/arch/um/include/mconsole_kern.h +++ b/arch/um/include/mconsole_kern.h @@ -18,10 +18,10 @@ struct mconsole_entry { struct mc_device { struct list_head list; char *name; - int (*config)(char *); + int (*config)(char *, char **); int (*get_config)(char *, char *, int, char **); int (*id)(char **, int *, int *); - int (*remove)(int); + int (*remove)(int, char **); }; #define CONFIG_CHUNK(str, size, current, chunk, end) \ @@ -50,14 +50,3 @@ static inline void mconsole_register_dev(struct mc_device *new) #endif #endif - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ diff --git a/arch/um/kernel/tt/gdb.c b/arch/um/kernel/tt/gdb.c index 786e4edd86c5..8eba8f7dca68 100644 --- a/arch/um/kernel/tt/gdb.c +++ b/arch/um/kernel/tt/gdb.c @@ -139,7 +139,7 @@ static void config_gdb_cb(void *arg) init_proxy(debugger_pid, 0, 0); } -int gdb_config(char *str) +int gdb_config(char *str, char **error_out) { struct gdb_data data; @@ -154,7 +154,7 @@ void remove_gdb_cb(void *unused) exit_debugger_cb(NULL); } -int gdb_remove(int unused) +int gdb_remove(int unused, char **error_out) { initial_thread_cb(remove_gdb_cb, NULL); return 0; diff --git a/arch/um/kernel/tt/gdb_kern.c b/arch/um/kernel/tt/gdb_kern.c index 68e1bf63cd0a..a1af96ef9ee2 100644 --- a/arch/um/kernel/tt/gdb_kern.c +++ b/arch/um/kernel/tt/gdb_kern.c @@ -8,8 +8,8 @@ #ifdef CONFIG_MCONSOLE -extern int gdb_config(char *str); -extern int gdb_remove(int n); +extern int gdb_config(char *str, char **error_out); +extern int gdb_remove(int n, char **error_out); static struct mc_device gdb_mc = { .name = "gdb", -- cgit v1.2.3 From 894be2a485b75bce9a4d45d3e431aafd4c89f1ea Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:43:54 -0800 Subject: [PATCH] uml: console whitespace and comment tidying Some comment and whitespace cleanups in the console and mconsole code. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/stdio_console.c | 2 -- arch/um/include/mconsole_kern.h | 2 +- 2 files changed, 1 insertion(+), 3 deletions(-) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index 3cbfe3a88607..0b1bca498049 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -30,8 +30,6 @@ #define MAX_TTYS (16) -/* ----------------------------------------------------------------------------- */ - /* Referenced only by tty_driver below - presumably it's locked correctly * by the tty driver. */ diff --git a/arch/um/include/mconsole_kern.h b/arch/um/include/mconsole_kern.h index 73030e52b2ce..d2fe07e78958 100644 --- a/arch/um/include/mconsole_kern.h +++ b/arch/um/include/mconsole_kern.h @@ -20,7 +20,7 @@ struct mc_device { char *name; int (*config)(char *, char **); int (*get_config)(char *, char *, int, char **); - int (*id)(char **, int *, int *); + int (*id)(char **, int *, int *); int (*remove)(int, char **); }; -- cgit v1.2.3 From a52f362f864f56238c9036f5c56f763a80e2ddd5 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:44:06 -0800 Subject: [PATCH] uml: mostly const a structure The chan_opts structure is mostly const, and needs no locking. Comment the lack of locking on the one field that can change. Make all the other fields const. It turned out that console_open_chan didn't use its chan_opts argument, so that is deleted from the function and its callers. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/chan_kern.c | 5 ++--- arch/um/drivers/ssl.c | 3 ++- arch/um/drivers/stdio_console.c | 3 ++- arch/um/include/chan_kern.h | 3 +-- arch/um/include/chan_user.h | 8 ++++---- 5 files changed, 11 insertions(+), 11 deletions(-) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c index bce9b3427b09..7b8baf146acc 100644 --- a/arch/um/drivers/chan_kern.c +++ b/arch/um/drivers/chan_kern.c @@ -354,8 +354,7 @@ int console_write_chan(struct list_head *chans, const char *buf, int len) return ret; } -int console_open_chan(struct line *line, struct console *co, - const struct chan_opts *opts) +int console_open_chan(struct line *line, struct console *co) { int err; @@ -363,7 +362,7 @@ int console_open_chan(struct line *line, struct console *co, if(err) return err; - printk("Console initialized on /dev/%s%d\n",co->name,co->index); + printk("Console initialized on /dev/%s%d\n", co->name, co->index); return 0; } diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c index fe400acc9751..475de52783e4 100644 --- a/arch/um/drivers/ssl.c +++ b/arch/um/drivers/ssl.c @@ -38,6 +38,7 @@ static void ssl_announce(char *dev_name, int dev) dev_name); } +/* Almost const, except that xterm_title may be changed in an initcall */ static struct chan_opts opts = { .announce = ssl_announce, .xterm_title = "Serial Line #%d", @@ -171,7 +172,7 @@ static int ssl_console_setup(struct console *co, char *options) { struct line *line = &serial_lines[co->index]; - return console_open_chan(line, co, &opts); + return console_open_chan(line, co); } static struct console ssl_cons = { diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index 0b1bca498049..a83c42c263b3 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -42,6 +42,7 @@ void stdio_announce(char *dev_name, int dev) dev_name); } +/* Almost const, except that xterm_title may be changed in an initcall */ static struct chan_opts opts = { .announce = stdio_announce, .xterm_title = "Virtual Console #%d", @@ -144,7 +145,7 @@ static int uml_console_setup(struct console *co, char *options) { struct line *line = &vts[co->index]; - return console_open_chan(line, co, &opts); + return console_open_chan(line, co); } static struct console stdiocons = { diff --git a/arch/um/include/chan_kern.h b/arch/um/include/chan_kern.h index 2d9aa7ef4c27..c4b41bb1035f 100644 --- a/arch/um/include/chan_kern.h +++ b/arch/um/include/chan_kern.h @@ -36,8 +36,7 @@ extern int write_chan(struct list_head *chans, const char *buf, int len, int write_irq); extern int console_write_chan(struct list_head *chans, const char *buf, int len); -extern int console_open_chan(struct line *line, struct console *co, - const struct chan_opts *opts); +extern int console_open_chan(struct line *line, struct console *co); extern void deactivate_chan(struct list_head *chans, int irq); extern void reactivate_chan(struct list_head *chans, int irq); extern void chan_enable_winch(struct list_head *chans, struct tty_struct *tty); diff --git a/arch/um/include/chan_user.h b/arch/um/include/chan_user.h index a795547a1dbd..ad671eb9edeb 100644 --- a/arch/um/include/chan_user.h +++ b/arch/um/include/chan_user.h @@ -9,11 +9,11 @@ #include "init.h" struct chan_opts { - void (*announce)(char *dev_name, int dev); + void (*const announce)(char *dev_name, int dev); char *xterm_title; - int raw; - unsigned long tramp_stack; - int in_kernel; + const int raw; + const unsigned long tramp_stack; + const int in_kernel; }; enum chan_init_pri { INIT_STATIC, INIT_ALL, INIT_ONE }; -- cgit v1.2.3 From d5c9ffc6c6d15d4f655236e26942a21ad61fe3ad Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:44:08 -0800 Subject: [PATCH] uml: console locking commentary and code cleanup Remove the last vestiges of devfs from console registration. Change the name of the function, plus remove a couple of unused fields from the line_driver structure. struct lines is no longer needed, all traces of it are gone. The only way that I can see to mark a structure as being almost-const is to individually const the fields. This is the case for the line_driver structure, which has only one modifiable field - a list_head in a sub-structure. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/line.c | 7 +++---- arch/um/drivers/ssl.c | 16 +++++++--------- arch/um/drivers/stdio_console.c | 17 +++++++---------- arch/um/include/line.h | 36 ++++++++++++++---------------------- 4 files changed, 31 insertions(+), 45 deletions(-) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c index e620ed46ed3f..433e572fb196 100644 --- a/arch/um/drivers/line.c +++ b/arch/um/drivers/line.c @@ -707,10 +707,9 @@ int line_remove(struct line *lines, unsigned int num, int n, char **error_out) return err; } -struct tty_driver *line_register_devfs(struct lines *set, - struct line_driver *line_driver, - const struct tty_operations *ops, - struct line *lines, int nlines) +struct tty_driver *register_lines(struct line_driver *line_driver, + const struct tty_operations *ops, + struct line *lines, int nlines) { int i; struct tty_driver *driver = alloc_tty_driver(nlines); diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c index 475de52783e4..fc22b9bd9153 100644 --- a/arch/um/drivers/ssl.c +++ b/arch/um/drivers/ssl.c @@ -51,6 +51,8 @@ static int ssl_config(char *str, char **error_out); static int ssl_get_config(char *dev, char *str, int size, char **error_out); static int ssl_remove(int n, char **error_out); + +/* Const, except for .mc.list */ static struct line_driver driver = { .name = "UML serial line", .device_name = "ttyS", @@ -62,8 +64,6 @@ static struct line_driver driver = { .read_irq_name = "ssl", .write_irq = SSL_WRITE_IRQ, .write_irq_name = "ssl-write", - .symlink_from = "serial", - .symlink_to = "tts", .mc = { .list = LIST_HEAD_INIT(driver.mc.list), .name = "ssl", @@ -74,14 +74,12 @@ static struct line_driver driver = { }, }; -/* The array is initialized by line_init, which is an initcall. The - * individual elements are protected by individual semaphores. +/* The array is initialized by line_init, at initcall time. The + * elements are locked individually as needed. */ static struct line serial_lines[NR_PORTS] = { [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) }; -static struct lines lines = LINES_INIT(NR_PORTS); - static int ssl_config(char *str, char **error_out) { return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts, @@ -175,6 +173,7 @@ static int ssl_console_setup(struct console *co, char *options) return console_open_chan(line, co); } +/* No locking for register_console call - relies on single-threaded initcalls */ static struct console ssl_cons = { .name = "ttyS", .write = ssl_console_write, @@ -190,9 +189,8 @@ static int ssl_init(void) printk(KERN_INFO "Initializing software serial port version %d\n", ssl_version); - ssl_driver = line_register_devfs(&lines, &driver, &ssl_ops, - serial_lines, - ARRAY_SIZE(serial_lines)); + ssl_driver = register_lines(&driver, &ssl_ops, serial_lines, + ARRAY_SIZE(serial_lines)); lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts); diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index a83c42c263b3..8dccdd193d94 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -55,6 +55,8 @@ static int con_config(char *str, char **error_out); static int con_get_config(char *dev, char *str, int size, char **error_out); static int con_remove(int n, char **con_remove); + +/* Const, except for .mc.list */ static struct line_driver driver = { .name = "UML console", .device_name = "tty", @@ -66,8 +68,6 @@ static struct line_driver driver = { .read_irq_name = "console", .write_irq = CONSOLE_WRITE_IRQ, .write_irq_name = "console-write", - .symlink_from = "ttys", - .symlink_to = "vc", .mc = { .name = "con", .config = con_config, @@ -77,10 +77,8 @@ static struct line_driver driver = { }, }; -static struct lines console_lines = LINES_INIT(MAX_TTYS); - -/* The array is initialized by line_init, which is an initcall. The - * individual elements are protected by individual semaphores. +/* The array is initialized by line_init, at initcall time. The + * elements are locked individually as needed. */ static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver), [ 1 ... MAX_TTYS - 1 ] = @@ -148,6 +146,7 @@ static int uml_console_setup(struct console *co, char *options) return console_open_chan(line, co); } +/* No locking for register_console call - relies on single-threaded initcalls */ static struct console stdiocons = { .name = "tty", .write = uml_console_write, @@ -155,16 +154,14 @@ static struct console stdiocons = { .setup = uml_console_setup, .flags = CON_PRINTBUFFER, .index = -1, - .data = &vts, }; int stdio_init(void) { char *new_title; - console_driver = line_register_devfs(&console_lines, &driver, - &console_ops, vts, - ARRAY_SIZE(vts)); + console_driver = register_lines(&driver, &console_ops, vts, + ARRAY_SIZE(vts)); if (console_driver == NULL) return -1; printk(KERN_INFO "Initialized stdio console driver\n"); diff --git a/arch/um/include/line.h b/arch/um/include/line.h index a2486b4cc9fe..3477a858eaa9 100644 --- a/arch/um/include/line.h +++ b/arch/um/include/line.h @@ -15,19 +15,18 @@ #include "chan_user.h" #include "mconsole_kern.h" +/* There's only one modifiable field in this - .mc.list */ struct line_driver { - char *name; - char *device_name; - short major; - short minor_start; - short type; - short subtype; - int read_irq; - char *read_irq_name; - int write_irq; - char *write_irq_name; - char *symlink_from; - char *symlink_to; + const char *name; + const char *device_name; + const short major; + const short minor_start; + const short type; + const short subtype; + const int read_irq; + const char *read_irq_name; + const int write_irq; + const char *write_irq_name; struct mc_device mc; }; @@ -67,12 +66,6 @@ struct line { .lock = SPIN_LOCK_UNLOCKED, \ .driver = d } -struct lines { - int num; -}; - -#define LINES_INIT(n) { .num = n } - extern void line_close(struct tty_struct *tty, struct file * filp); extern int line_open(struct line *lines, struct tty_struct *tty); extern int line_setup(struct line *lines, unsigned int sizeof_lines, @@ -94,10 +87,9 @@ extern char *add_xterm_umid(char *base); extern int line_setup_irq(int fd, int input, int output, struct line *line, void *data); extern void line_close_chan(struct line *line); -extern struct tty_driver * line_register_devfs(struct lines *set, - struct line_driver *line_driver, - const struct tty_operations *driver, - struct line *lines, int nlines); +extern struct tty_driver *register_lines(struct line_driver *line_driver, + const struct tty_operations *driver, + struct line *lines, int nlines); extern void lines_init(struct line *lines, int nlines, struct chan_opts *opts); extern void close_lines(struct line *lines, int nlines); -- cgit v1.2.3 From c0961c1804c46bf5bb253e1bd6bc93e4627b79a1 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sat, 10 Feb 2007 01:44:11 -0800 Subject: [PATCH] uml: initialize a list head We need to initialize lists properly. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/stdio_console.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/um/drivers/stdio_console.c') diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index 8dccdd193d94..7ff0b0fc37e7 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -69,6 +69,7 @@ static struct line_driver driver = { .write_irq = CONSOLE_WRITE_IRQ, .write_irq_name = "console-write", .mc = { + .list = LIST_HEAD_INIT(driver.mc.list), .name = "con", .config = con_config, .get_config = con_get_config, -- cgit v1.2.3