From 7170be5f586b59bdcdab082778a5d9203ba7b667 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Sat, 14 Jan 2006 13:20:38 -0800 Subject: [PATCH] convert /proc/devices to use seq_file interface A Christoph suggested that the /proc/devices file be converted to use the seq_file interface. This patch does that. I've obxerved one or two installation that had sufficiently large sans that they overran the 4k limit on /proc/devices. Signed-off-by: Neil Horman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/proc_misc.c | 160 ++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 150 insertions(+), 10 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c index 63bf6c00fa0c..8f8014285a34 100644 --- a/fs/proc/proc_misc.c +++ b/fs/proc/proc_misc.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -62,7 +63,6 @@ */ extern int get_hardware_list(char *); extern int get_stram_list(char *); -extern int get_chrdev_list(char *); extern int get_filesystem_list(char *); extern int get_exec_domain_list(char *); extern int get_dma_list(char *); @@ -248,6 +248,154 @@ static int cpuinfo_open(struct inode *inode, struct file *file) { return seq_open(file, &cpuinfo_op); } + +enum devinfo_states { + CHR_HDR, + CHR_LIST, + BLK_HDR, + BLK_LIST, + DEVINFO_DONE +}; + +struct devinfo_state { + void *chrdev; + void *blkdev; + unsigned int num_records; + unsigned int cur_record; + enum devinfo_states state; +}; + +static void *devinfo_start(struct seq_file *f, loff_t *pos) +{ + struct devinfo_state *info = f->private; + + if (*pos) { + if ((info) && (*pos <= info->num_records)) + return info; + return NULL; + } + info = kmalloc(sizeof(*info), GFP_KERNEL); + f->private = info; + info->chrdev = acquire_chrdev_list(); + info->blkdev = acquire_blkdev_list(); + info->state = CHR_HDR; + info->num_records = count_chrdev_list(); + info->num_records += count_blkdev_list(); + info->num_records += 2; /* Character and Block headers */ + *pos = 1; + info->cur_record = *pos; + return info; +} + +static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos) +{ + int idummy; + char *ndummy; + struct devinfo_state *info = f->private; + + switch (info->state) { + case CHR_HDR: + info->state = CHR_LIST; + (*pos)++; + /*fallthrough*/ + case CHR_LIST: + if (get_chrdev_info(info->chrdev,&idummy,&ndummy)) { + /* + * The character dev list is complete + */ + info->state = BLK_HDR; + } else { + info->chrdev = get_next_chrdev(info->chrdev); + } + (*pos)++; + break; + case BLK_HDR: + info->state = BLK_LIST; + (*pos)++; + break; + case BLK_LIST: + if (get_blkdev_info(info->blkdev,&idummy,&ndummy)) { + /* + * The block dev list is complete + */ + info->state = DEVINFO_DONE; + } else { + info->blkdev = get_next_blkdev(info->blkdev); + } + (*pos)++; + break; + case DEVINFO_DONE: + (*pos)++; + info->cur_record = *pos; + info = NULL; + break; + default: + break; + } + if (info) + info->cur_record = *pos; + return info; +} + +static void devinfo_stop(struct seq_file *f, void *v) +{ + struct devinfo_state *info = f->private; + + if (info) { + release_chrdev_list(info->chrdev); + release_blkdev_list(info->blkdev); + f->private = NULL; + kfree(info); + } +} + +static int devinfo_show(struct seq_file *f, void *arg) +{ + int major; + char *name; + struct devinfo_state *info = f->private; + + switch(info->state) { + case CHR_HDR: + seq_printf(f,"Character devices:\n"); + /* fallthrough */ + case CHR_LIST: + if (!get_chrdev_info(info->chrdev,&major,&name)) + seq_printf(f,"%3d %s\n",major,name); + break; + case BLK_HDR: + seq_printf(f,"\nBlock devices:\n"); + /* fallthrough */ + case BLK_LIST: + if (!get_blkdev_info(info->blkdev,&major,&name)) + seq_printf(f,"%3d %s\n",major,name); + break; + default: + break; + } + + return 0; +} + +static struct seq_operations devinfo_op = { + .start = devinfo_start, + .next = devinfo_next, + .stop = devinfo_stop, + .show = devinfo_show, +}; + +static int devinfo_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &devinfo_op); +} + +static struct file_operations proc_devinfo_operations = { + .open = devinfo_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + static struct file_operations proc_cpuinfo_operations = { .open = cpuinfo_open, .read = seq_read, @@ -450,14 +598,6 @@ static struct file_operations proc_stat_operations = { .release = single_release, }; -static int devices_read_proc(char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - int len = get_chrdev_list(page); - len += get_blkdev_list(page+len, len); - return proc_calc_metrics(page, start, off, count, eof, len); -} - /* * /proc/interrupts */ @@ -582,7 +722,6 @@ void __init proc_misc_init(void) #ifdef CONFIG_STRAM_PROC {"stram", stram_read_proc}, #endif - {"devices", devices_read_proc}, {"filesystems", filesystems_read_proc}, {"cmdline", cmdline_read_proc}, {"locks", locks_read_proc}, @@ -598,6 +737,7 @@ void __init proc_misc_init(void) entry = create_proc_entry("kmsg", S_IRUSR, &proc_root); if (entry) entry->proc_fops = &proc_kmsg_operations; + create_seq_entry("devices", 0, &proc_devinfo_operations); create_seq_entry("cpuinfo", 0, &proc_cpuinfo_operations); create_seq_entry("partitions", 0, &proc_partitions_operations); create_seq_entry("stat", 0, &proc_stat_operations); -- cgit v1.2.3-59-g8ed1b