/*
       *  linux/fs/proc/proc_misc.c
       *
       *  linux/fs/proc/array.c
       *  Copyright (C) 1992  by Linus Torvalds
       *  based on ideas by Darren Senn
       *
       *  This used to be the part of array.c. See the rest of history and credits
       *  there. I took this into a separate file and switched the thing to generic
       *  proc_file_inode_operations, leaving in array.c only per-process stuff.
       *  Inumbers allocation made dynamic (via create_proc_entry()).  AV, May 1999.
       *
       * Changes:
       * Fulton Green      :  Encapsulated position metric calculations.
       *			<kernel@FultonGreen.com>
       */
      
      #include <linux/types.h>
      #include <linux/errno.h>
      #include <linux/sched.h>
      #include <linux/kernel.h>
      #include <linux/kernel_stat.h>
      #include <linux/tty.h>
      #include <linux/string.h>
      #include <linux/mman.h>
      #include <linux/proc_fs.h>
      #include <linux/ioport.h>
      #include <linux/config.h>
      #include <linux/mm.h>
      #include <linux/pagemap.h>
      #include <linux/swap.h>
      #include <linux/slab.h>
      #include <linux/smp.h>
      #include <linux/signal.h>
      #include <linux/module.h>
      #include <linux/init.h>
      #include <linux/smp_lock.h>
      
      #include <asm/uaccess.h>
      #include <asm/pgtable.h>
      #include <asm/io.h>
      
      
      #define LOAD_INT(x) ((x) >> FSHIFT)
      #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
      /*
       * Warning: stuff below (imported functions) assumes that its output will fit
       * into one page. For some of those functions it may be wrong. Moreover, we
       * have a way to deal with that gracefully. Right now I used straightforward
       * wrappers, but this needs further analysis wrt potential overflows.
       */
      extern int get_cpuinfo(char *);
      extern int get_hardware_list(char *);
      extern int get_stram_list(char *);
      #ifdef CONFIG_DEBUG_MALLOC
      extern int get_malloc(char * buffer);
      #endif
      #ifdef CONFIG_MODULES
      extern int get_module_list(char *);
      extern int get_ksyms_list(char *, char **, off_t, int);
      #endif
      extern int get_device_list(char *);
      extern int get_partition_list(char *, char **, off_t, int);
      extern int get_filesystem_list(char *);
      extern int get_filesystem_info(char *);
      extern int get_exec_domain_list(char *);
      extern int get_irq_list(char *);
      extern int get_dma_list(char *);
      extern int get_locks_status (char *, char **, off_t, int);
      extern int get_swaparea_info (char *);
      #ifdef CONFIG_SGI_DS1286
      extern int get_ds1286_status(char *);
      #endif
      
  75  static int proc_calc_metrics(char *page, char **start, off_t off,
      				 int count, int *eof, int len)
      {
  78  	if (len <= off+count) *eof = 1;
      	*start = page + off;
      	len -= off;
  81  	if (len>count) len = count;
  82  	if (len<0) len = 0;
  83  	return len;
      }
      
  86  static int loadavg_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int a, b, c;
      	int len;
      
      	a = avenrun[0] + (FIXED_1/200);
      	b = avenrun[1] + (FIXED_1/200);
      	c = avenrun[2] + (FIXED_1/200);
      	len = sprintf(page,"%d.%02d %d.%02d %d.%02d %d/%d %d\n",
      		LOAD_INT(a), LOAD_FRAC(a),
      		LOAD_INT(b), LOAD_FRAC(b),
      		LOAD_INT(c), LOAD_FRAC(c),
      		nr_running, nr_threads, last_pid);
 100  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 103  static int uptime_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	unsigned long uptime;
      	unsigned long idle;
      	int len;
      
      	uptime = jiffies;
      	idle = init_tasks[0]->times.tms_utime + init_tasks[0]->times.tms_stime;
      
      	/* The formula for the fraction parts really is ((t * 100) / HZ) % 100, but
      	   that would overflow about every five days at HZ == 100.
      	   Therefore the identity a = (a / b) * b + a % b is used so that it is
      	   calculated as (((t / HZ) * 100) + ((t % HZ) * 100) / HZ) % 100.
      	   The part in front of the '+' always evaluates as 0 (mod 100). All divisions
      	   in the above formulas are truncating. For HZ being a power of 10, the
      	   calculations simplify to the version in the #else part (if the printf
      	   format is adapted to the same number of digits as zeroes in HZ.
      	 */
      #if HZ!=100
      	len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
      		uptime / HZ,
      		(((uptime % HZ) * 100) / HZ) % 100,
      		idle / HZ,
      		(((idle % HZ) * 100) / HZ) % 100);
      #else
      	len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
      		uptime / HZ,
      		uptime % HZ,
      		idle / HZ,
      		idle % HZ);
      #endif
 135  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 138  static int meminfo_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	struct sysinfo i;
      	int len;
      
      /*
       * display in kilobytes.
       */
      #define K(x) ((x) << (PAGE_SHIFT - 10))
      #define B(x) ((x) << PAGE_SHIFT)
              si_meminfo(&i);
              si_swapinfo(&i);
              len = sprintf(page, "        total:    used:    free:  shared: buffers:  cached:\n"
                      "Mem:  %8lu %8lu %8lu %8lu %8lu %8u\n"
                      "Swap: %8lu %8lu %8lu\n",
                      B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
                      B(i.sharedram), B(i.bufferram),
                      B(atomic_read(&page_cache_size)), B(i.totalswap),
                      B(i.totalswap-i.freeswap), B(i.freeswap));
              /*
               * Tagged format, for easy grepping and expansion.
               * The above will go away eventually, once the tools
               * have been updated.
               */
              len += sprintf(page+len,
                      "MemTotal:     %8lu kB\n"
                      "MemFree:      %8lu kB\n"
                      "MemShared:    %8lu kB\n"
                      "Buffers:      %8lu kB\n"
                      "Cached:       %8u kB\n"
      		"Active:       %8u kB\n"
      		"Inact_dirty:  %8u kB\n"
      		"Inact_clean:  %8u kB\n"
      		"Inact_target: %8lu kB\n"
                      "HighTotal:    %8lu kB\n"
                      "HighFree:     %8lu kB\n"
                      "LowTotal:     %8lu kB\n"
                      "LowFree:      %8lu kB\n"
                      "SwapTotal:    %8lu kB\n"
                      "SwapFree:     %8lu kB\n",
                      K(i.totalram),
                      K(i.freeram),
                      K(i.sharedram),
                      K(i.bufferram),
                      K(atomic_read(&page_cache_size)),
      		K(nr_active_pages),
      		K(nr_inactive_dirty_pages),
      		K(nr_inactive_clean_pages()),
      		K(inactive_target),
                      K(i.totalhigh),
                      K(i.freehigh),
                      K(i.totalram-i.totalhigh),
                      K(i.freeram-i.freehigh),
                      K(i.totalswap),
                      K(i.freeswap));
      
 195  	return proc_calc_metrics(page, start, off, count, eof, len);
      #undef B
      #undef K
      }
      
 200  static int version_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	extern char *linux_banner;
      	int len;
      
      	strcpy(page, linux_banner);
      	len = strlen(page);
 208  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 211  static int cpuinfo_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_cpuinfo(page);
 215  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
      #ifdef CONFIG_PROC_HARDWARE
      static int hardware_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_hardware_list(page);
      	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      #endif
      
      #ifdef CONFIG_STRAM_PROC
      static int stram_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_stram_list(page);
      	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      #endif
      
      #ifdef CONFIG_DEBUG_MALLOC
      static int malloc_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_malloc(page);
      	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      #endif
      
      #ifdef CONFIG_MODULES
 246  static int modules_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_module_list(page);
 250  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 253  static int ksyms_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_ksyms_list(page, start, off, count);
 257  	if (len < count) *eof = 1;
 258  	return len;
      }
      #endif
      
 262  static int kstat_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int i, len;
      	extern unsigned long total_forks;
      	unsigned long jif = jiffies;
      	unsigned int sum = 0, user = 0, nice = 0, system = 0;
      	int major, disk;
      
 271  	for (i = 0 ; i < smp_num_cpus; i++) {
      		int cpu = cpu_logical_map(i), j;
      
      		user += kstat.per_cpu_user[cpu];
      		nice += kstat.per_cpu_nice[cpu];
      		system += kstat.per_cpu_system[cpu];
 277  		for (j = 0 ; j < NR_IRQS ; j++)
      			sum += kstat.irqs[cpu][j];
      	}
      
      	len = sprintf(page, "cpu  %u %u %u %lu\n", user, nice, system,
      		      jif * smp_num_cpus - (user + nice + system));
 283  	for (i = 0 ; i < smp_num_cpus; i++)
      		len += sprintf(page + len, "cpu%d %u %u %u %lu\n",
      			i,
      			kstat.per_cpu_user[cpu_logical_map(i)],
      			kstat.per_cpu_nice[cpu_logical_map(i)],
      			kstat.per_cpu_system[cpu_logical_map(i)],
      			jif - (  kstat.per_cpu_user[cpu_logical_map(i)] \
      			           + kstat.per_cpu_nice[cpu_logical_map(i)] \
      			           + kstat.per_cpu_system[cpu_logical_map(i)]));
      	len += sprintf(page + len,
      		"page %u %u\n"
                      "swap %u %u\n"
      		"intr %u",
      			kstat.pgpgin,
      			kstat.pgpgout,
      			kstat.pswpin,
      			kstat.pswpout,
      			sum
      	);
 302  	for (i = 0 ; i < NR_IRQS ; i++)
      		len += sprintf(page + len, " %u", kstat_irqs(i));
      
      	len += sprintf(page + len, "\ndisk_io: ");
      
 307  	for (major = 0; major < DK_MAX_MAJOR; major++) {
 308  		for (disk = 0; disk < DK_MAX_DISK; disk++) {
      			int active = kstat.dk_drive[major][disk] +
      				kstat.dk_drive_rblk[major][disk] +
      				kstat.dk_drive_wblk[major][disk];
 312  			if (active)
      				len += sprintf(page + len,
      					"(%u,%u):(%u,%u,%u,%u,%u) ",
      					major, disk,
      					kstat.dk_drive[major][disk],
      					kstat.dk_drive_rio[major][disk],
      					kstat.dk_drive_rblk[major][disk],
      					kstat.dk_drive_wio[major][disk],
      					kstat.dk_drive_wblk[major][disk]
      			);
      		}
      	}
      
      	len += sprintf(page + len,
      		"\nctxt %u\n"
      		"btime %lu\n"
      		"processes %lu\n",
      		kstat.context_swtch,
      		xtime.tv_sec - jif / HZ,
      		total_forks);
      
 333  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 336  static int devices_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_device_list(page);
 340  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 343  static int partitions_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_partition_list(page, start, off, count);
 347  	if (len < count) *eof = 1;
 348  	return len;
      }
      
      #if !defined(CONFIG_ARCH_S390)
 352  static int interrupts_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_irq_list(page);
 356  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      #endif
      
 360  static int filesystems_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_filesystem_list(page);
 364  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 367  static int dma_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_dma_list(page);
 371  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 374  static int ioports_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_ioport_list(page);
 378  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 381  static int cmdline_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	extern char saved_command_line[];
      	int len;
      
      	len = sprintf(page, "%s\n", saved_command_line);
      	len = strlen(page);
 389  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
      #ifdef CONFIG_SGI_DS1286
      static int ds1286_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_ds1286_status(page);
      	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      #endif
      
 401  static int locks_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len;
 405  	lock_kernel();
      	len = get_locks_status(page, start, off, count);
 407  	unlock_kernel();
 408  	if (len < count) *eof = 1;
 409  	return len;
      }
      
 412  static int mounts_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_filesystem_info(page);
 416  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 419  static int execdomains_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_exec_domain_list(page);
 423  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 426  static int swaps_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_swaparea_info(page);
 430  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
 433  static int memory_read_proc(char *page, char **start, off_t off,
      				 int count, int *eof, void *data)
      {
      	int len = get_mem_list(page);
 437  	return proc_calc_metrics(page, start, off, count, eof, len);
      }
      
      /*
       * This function accesses profiling information. The returned data is
       * binary: the sampling step and the actual contents of the profile
       * buffer. Use of the program readprofile is recommended in order to
       * get meaningful info out of these data.
       */
 446  static ssize_t read_profile(struct file *file, char *buf,
      			    size_t count, loff_t *ppos)
      {
      	unsigned long p = *ppos;
      	ssize_t read;
      	char * pnt;
      	unsigned int sample_step = 1 << prof_shift;
      
 454  	if (p >= (prof_len+1)*sizeof(unsigned int))
 455  		return 0;
 456  	if (count > (prof_len+1)*sizeof(unsigned int) - p)
      		count = (prof_len+1)*sizeof(unsigned int) - p;
      	read = 0;
      
 460  	while (p < sizeof(unsigned int) && count > 0) {
      		put_user(*((char *)(&sample_step)+p),buf);
      		buf++; p++; count--; read++;
      	}
      	pnt = (char *)prof_buffer + p - sizeof(unsigned int);
      	copy_to_user(buf,(void *)pnt,count);
      	read += count;
      	*ppos += read;
 468  	return read;
      }
      
      /*
       * Writing to /proc/profile resets the counters
       *
       * Writing a 'profiling multiplier' value into it also re-sets the profiling
       * interrupt frequency, on architectures that support this.
       */
 477  static ssize_t write_profile(struct file * file, const char * buf,
      			     size_t count, loff_t *ppos)
      {
      #ifdef CONFIG_SMP
      	extern int setup_profiling_timer (unsigned int multiplier);
      
      	if (count==sizeof(int)) {
      		unsigned int multiplier;
      
      		if (copy_from_user(&multiplier, buf, sizeof(int)))
      			return -EFAULT;
      
      		if (setup_profiling_timer(multiplier))
      			return -EINVAL;
      	}
      #endif
      
      	memset(prof_buffer, 0, prof_len * sizeof(*prof_buffer));
 495  	return count;
      }
      
      static struct file_operations proc_profile_operations = {
      	read:		read_profile,
      	write:		write_profile,
      };
      
      struct proc_dir_entry *proc_root_kcore;
      
 505  void __init proc_misc_init(void)
      {
      	struct proc_dir_entry *entry;
      	static struct {
      		char *name;
      		int (*read_proc)(char*,char**,off_t,int,int*,void*);
      	} *p, simple_ones[] = {
      		{"loadavg",     loadavg_read_proc},
      		{"uptime",	uptime_read_proc},
      		{"meminfo",	meminfo_read_proc},
      		{"version",	version_read_proc},
      		{"cpuinfo",	cpuinfo_read_proc},
      #ifdef CONFIG_PROC_HARDWARE
      		{"hardware",	hardware_read_proc},
      #endif
      #ifdef CONFIG_STRAM_PROC
      		{"stram",	stram_read_proc},
      #endif
      #ifdef CONFIG_DEBUG_MALLOC
      		{"malloc",	malloc_read_proc},
      #endif
      #ifdef CONFIG_MODULES
      		{"modules",	modules_read_proc},
      		{"ksyms",	ksyms_read_proc},
      #endif
      		{"stat",	kstat_read_proc},
      		{"devices",	devices_read_proc},
      		{"partitions",	partitions_read_proc},
      #if !defined(CONFIG_ARCH_S390)
      		{"interrupts",	interrupts_read_proc},
      #endif
      		{"filesystems",	filesystems_read_proc},
      		{"dma",		dma_read_proc},
      		{"ioports",	ioports_read_proc},
      		{"cmdline",	cmdline_read_proc},
      #ifdef CONFIG_SGI_DS1286
      		{"rtc",		ds1286_read_proc},
      #endif
      		{"locks",	locks_read_proc},
      		{"mounts",	mounts_read_proc},
      		{"swaps",	swaps_read_proc},
      		{"iomem",	memory_read_proc},
      		{"execdomains",	execdomains_read_proc},
      		{NULL,}
      	};
 550  	for (p = simple_ones; p->name; p++)
      		create_proc_read_entry(p->name, 0, NULL, p->read_proc, NULL);
      
      	/* And now for trickier ones */
      	entry = create_proc_entry("kmsg", S_IRUSR, &proc_root);
 555  	if (entry)
      		entry->proc_fops = &proc_kmsg_operations;
      	proc_root_kcore = create_proc_entry("kcore", S_IRUSR, NULL);
 558  	if (proc_root_kcore) {
      		proc_root_kcore->proc_fops = &proc_kcore_operations;
      		proc_root_kcore->size =
      				(size_t)high_memory - PAGE_OFFSET + PAGE_SIZE;
      	}
 563  	if (prof_shift) {
      		entry = create_proc_entry("profile", S_IWUSR | S_IRUGO, NULL);
 565  		if (entry) {
      			entry->proc_fops = &proc_profile_operations;
      			entry->size = (1+prof_len) * sizeof(unsigned int);
      		}
      	}
      #ifdef __powerpc__
      	{
      		extern struct file_operations ppc_htab_operations;
      		entry = create_proc_entry("ppc_htab", S_IRUGO|S_IWUSR, NULL);
      		if (entry)
      			entry->proc_fops = &ppc_htab_operations;
      	}
      #endif
      	entry = create_proc_read_entry("slabinfo", S_IWUSR | S_IRUGO, NULL,
      				       slabinfo_read_proc, NULL);
 580  	if (entry)
      		entry->write_proc = slabinfo_write_proc;
      }