fs/proc/proc_misc.c

   1 /*
   2  *  linux/fs/proc/proc_misc.c
   3  *
   4  *  linux/fs/proc/array.c
   5  *  Copyright (C) 1992  by Linus Torvalds
   6  *  based on ideas by Darren Senn
   7  *
   8  *  This used to be the part of array.c. See the rest of history and credits
   9  *  there. I took this into a separate file and switched the thing to generic
  10  *  proc_file_inode_operations, leaving in array.c only per-process stuff.
  11  *  Inumbers allocation made dynamic (via create_proc_entry()).  AV, May 1999.
  12  *
  13  * Changes:
  14  * Fulton Green      :  Encapsulated position metric calculations.
  15  *                      <kernel@FultonGreen.com>
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/errno.h>
  20 #include <linux/time.h>
  21 #include <linux/kernel.h>
  22 #include <linux/kernel_stat.h>
  23 #include <linux/fs.h>
  24 #include <linux/tty.h>
  25 #include <linux/string.h>
  26 #include <linux/mman.h>
  27 #include <linux/quicklist.h>
  28 #include <linux/proc_fs.h>
  29 #include <linux/ioport.h>
  30 #include <linux/mm.h>
  31 #include <linux/mmzone.h>
  32 #include <linux/pagemap.h>
  33 #include <linux/irq.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/swap.h>
  36 #include <linux/slab.h>
  37 #include <linux/genhd.h>
  38 #include <linux/smp.h>
  39 #include <linux/signal.h>
  40 #include <linux/module.h>
  41 #include <linux/init.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/times.h>
  44 #include <linux/profile.h>
  45 #include <linux/utsname.h>
  46 #include <linux/blkdev.h>
  47 #include <linux/hugetlb.h>
  48 #include <linux/jiffies.h>
  49 #include <linux/vmalloc.h>
  50 #include <linux/crash_dump.h>
  51 #include <linux/pid_namespace.h>
  52 #include <linux/bootmem.h>
  53 #include <asm/uaccess.h>
  54 #include <asm/pgtable.h>
  55 #include <asm/io.h>
  56 #include <asm/tlb.h>
  57 #include <asm/div64.h>
  58 #include "internal.h"
  59
  60 static int fragmentation_open(struct inode *inode, struct file *file)
  61 {
  62         (void)inode;
  63         return seq_open(file, &fragmentation_op);
  64 }
  65
  66 static const struct file_operations fragmentation_file_operations = {
  67         .open           = fragmentation_open,
  68         .read           = seq_read,
  69         .llseek         = seq_lseek,
  70         .release        = seq_release,
  71 };
  72
  73 static int pagetypeinfo_open(struct inode *inode, struct file *file)
  74 {
  75         return seq_open(file, &pagetypeinfo_op);
  76 }
  77
  78 static const struct file_operations pagetypeinfo_file_ops = {
  79         .open           = pagetypeinfo_open,
  80         .read           = seq_read,
  81         .llseek         = seq_lseek,
  82         .release        = seq_release,
  83 };
  84
  85 static int zoneinfo_open(struct inode *inode, struct file *file)
  86 {
  87         return seq_open(file, &zoneinfo_op);
  88 }
  89
  90 static const struct file_operations proc_zoneinfo_file_operations = {
  91         .open           = zoneinfo_open,
  92         .read           = seq_read,
  93         .llseek         = seq_lseek,
  94         .release        = seq_release,
  95 };
  96
  97 static int vmstat_open(struct inode *inode, struct file *file)
  98 {
  99         return seq_open(file, &vmstat_op);
 100 }
 101 static const struct file_operations proc_vmstat_file_operations = {
 102         .open           = vmstat_open,
 103         .read           = seq_read,
 104         .llseek         = seq_lseek,
 105         .release        = seq_release,
 106 };
 107
 108 #ifdef CONFIG_BLOCK
 109 static int diskstats_open(struct inode *inode, struct file *file)
 110 {
 111         return seq_open(file, &diskstats_op);
 112 }
 113 static const struct file_operations proc_diskstats_operations = {
 114         .open           = diskstats_open,
 115         .read           = seq_read,
 116         .llseek         = seq_lseek,
 117         .release        = seq_release,
 118 };
 119 #endif
 120
 121 #ifdef CONFIG_MODULES
 122 extern const struct seq_operations modules_op;
 123 static int modules_open(struct inode *inode, struct file *file)
 124 {
 125         return seq_open(file, &modules_op);
 126 }
 127 static const struct file_operations proc_modules_operations = {
 128         .open           = modules_open,
 129         .read           = seq_read,
 130         .llseek         = seq_lseek,
 131         .release        = seq_release,
 132 };
 133 #endif
 134
 135 #ifdef CONFIG_SLABINFO
 136 static int slabinfo_open(struct inode *inode, struct file *file)
 137 {
 138         return seq_open(file, &slabinfo_op);
 139 }
 140 static const struct file_operations proc_slabinfo_operations = {
 141         .open           = slabinfo_open,
 142         .read           = seq_read,
 143         .write          = slabinfo_write,
 144         .llseek         = seq_lseek,
 145         .release        = seq_release,
 146 };
 147 #endif
 148
 149 #ifdef CONFIG_MMU
 150 static int vmalloc_open(struct inode *inode, struct file *file)
 151 {
 152         unsigned int *ptr = NULL;
 153         int ret;
 154
 155         if (NUMA_BUILD)
 156                 ptr = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL);
 157         ret = seq_open(file, &vmalloc_op);
 158         if (!ret) {
 159                 struct seq_file *m = file->private_data;
 160                 m->private = ptr;
 161         } else
 162                 kfree(ptr);
 163         return ret;
 164 }
 165
 166 static const struct file_operations proc_vmalloc_operations = {
 167         .open           = vmalloc_open,
 168         .read           = seq_read,
 169         .llseek         = seq_lseek,
 170         .release        = seq_release_private,
 171 };
 172 #endif
 173
 174 #ifdef CONFIG_PROC_PAGE_MONITOR
 175 #define KPMSIZE sizeof(u64)
 176 #define KPMMASK (KPMSIZE - 1)
 177 /* /proc/kpagecount - an array exposing page counts
 178  *
 179  * Each entry is a u64 representing the corresponding
 180  * physical page count.
 181  */
 182 static ssize_t kpagecount_read(struct file *file, char __user *buf,
 183                              size_t count, loff_t *ppos)
 184 {
 185         u64 __user *out = (u64 __user *)buf;
 186         struct page *ppage;
 187         unsigned long src = *ppos;
 188         unsigned long pfn;
 189         ssize_t ret = 0;
 190         u64 pcount;
 191
 192         pfn = src / KPMSIZE;
 193         count = min_t(size_t, count, (max_pfn * KPMSIZE) - src);
 194         if (src & KPMMASK || count & KPMMASK)
 195                 return -EINVAL;
 196
 197         while (count > 0) {
 198                 ppage = NULL;
 199                 if (pfn_valid(pfn))
 200                         ppage = pfn_to_page(pfn);
 201                 pfn++;
 202                 if (!ppage)
 203                         pcount = 0;
 204                 else
 205                         pcount = page_mapcount(ppage);
 206
 207                 if (put_user(pcount, out++)) {
 208                         ret = -EFAULT;
 209                         break;
 210                 }
 211
 212                 count -= KPMSIZE;
 213         }
 214
 215         *ppos += (char __user *)out - buf;
 216         if (!ret)
 217                 ret = (char __user *)out - buf;
 218         return ret;
 219 }
 220
 221 static struct file_operations proc_kpagecount_operations = {
 222         .llseek = mem_lseek,
 223         .read = kpagecount_read,
 224 };
 225
 226 /* /proc/kpageflags - an array exposing page flags
 227  *
 228  * Each entry is a u64 representing the corresponding
 229  * physical page flags.
 230  */
 231
 232 /* These macros are used to decouple internal flags from exported ones */
 233
 234 #define KPF_LOCKED     0
 235 #define KPF_ERROR      1
 236 #define KPF_REFERENCED 2
 237 #define KPF_UPTODATE   3
 238 #define KPF_DIRTY      4
 239 #define KPF_LRU        5
 240 #define KPF_ACTIVE     6
 241 #define KPF_SLAB       7
 242 #define KPF_WRITEBACK  8
 243 #define KPF_RECLAIM    9
 244 #define KPF_BUDDY     10
 245
 246 #define kpf_copy_bit(flags, srcpos, dstpos) (((flags >> srcpos) & 1) << dstpos)
 247
 248 static ssize_t kpageflags_read(struct file *file, char __user *buf,
 249                              size_t count, loff_t *ppos)
 250 {
 251         u64 __user *out = (u64 __user *)buf;
 252         struct page *ppage;
 253         unsigned long src = *ppos;
 254         unsigned long pfn;
 255         ssize_t ret = 0;
 256         u64 kflags, uflags;
 257
 258         pfn = src / KPMSIZE;
 259         count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src);
 260         if (src & KPMMASK || count & KPMMASK)
 261                 return -EINVAL;
 262
 263         while (count > 0) {
 264                 ppage = NULL;
 265                 if (pfn_valid(pfn))
 266                         ppage = pfn_to_page(pfn);
 267                 pfn++;
 268                 if (!ppage)
 269                         kflags = 0;
 270                 else
 271                         kflags = ppage->flags;
 272
 273                 uflags = kpf_copy_bit(KPF_LOCKED, PG_locked, kflags) |
 274                         kpf_copy_bit(kflags, KPF_ERROR, PG_error) |
 275                         kpf_copy_bit(kflags, KPF_REFERENCED, PG_referenced) |
 276                         kpf_copy_bit(kflags, KPF_UPTODATE, PG_uptodate) |
 277                         kpf_copy_bit(kflags, KPF_DIRTY, PG_dirty) |
 278                         kpf_copy_bit(kflags, KPF_LRU, PG_lru) |
 279                         kpf_copy_bit(kflags, KPF_ACTIVE, PG_active) |
 280                         kpf_copy_bit(kflags, KPF_SLAB, PG_slab) |
 281                         kpf_copy_bit(kflags, KPF_WRITEBACK, PG_writeback) |
 282                         kpf_copy_bit(kflags, KPF_RECLAIM, PG_reclaim) |
 283                         kpf_copy_bit(kflags, KPF_BUDDY, PG_buddy);
 284
 285                 if (put_user(uflags, out++)) {
 286                         ret = -EFAULT;
 287                         break;
 288                 }
 289
 290                 count -= KPMSIZE;
 291         }
 292
 293         *ppos += (char __user *)out - buf;
 294         if (!ret)
 295                 ret = (char __user *)out - buf;
 296         return ret;
 297 }
 298
 299 static struct file_operations proc_kpageflags_operations = {
 300         .llseek = mem_lseek,
 301         .read = kpageflags_read,
 302 };
 303 #endif /* CONFIG_PROC_PAGE_MONITOR */
 304
 305 struct proc_dir_entry *proc_root_kcore;
 306
 307 void __init proc_misc_init(void)
 308 {
 309         proc_symlink("mounts", NULL, "self/mounts");
 310
 311         /* And now for trickier ones */
 312 #ifdef CONFIG_SLABINFO
 313         proc_create("slabinfo",S_IWUSR|S_IRUGO,NULL,&proc_slabinfo_operations);
 314 #endif
 315 #ifdef CONFIG_MMU
 316         proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
 317 #endif
 318         proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
 319         proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops);
 320         proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
 321         proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
 322 #ifdef CONFIG_BLOCK
 323         proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
 324 #endif
 325 #ifdef CONFIG_MODULES
 326         proc_create("modules", 0, NULL, &proc_modules_operations);
 327 #endif
 328 #ifdef CONFIG_SCHEDSTATS
 329         proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
 330 #endif
 331 #ifdef CONFIG_PROC_KCORE
 332         proc_root_kcore = proc_create("kcore", S_IRUSR, NULL, &proc_kcore_operations);
 333         if (proc_root_kcore)
 334                 proc_root_kcore->size =
 335                                 (size_t)high_memory - PAGE_OFFSET + PAGE_SIZE;
 336 #endif
 337 #ifdef CONFIG_PROC_PAGE_MONITOR
 338         proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations);
 339         proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations);
 340 #endif
 341 #ifdef CONFIG_PROC_VMCORE
 342         proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations);
 343 #endif
 344 }