1 files changed, 450 insertions, 163 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 8686b0f5fc12..997080f00e0b 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -37,6 +37,7 @@
 #include <linux/highuid.h>
 #include <linux/writeback.h>
 #include <linux/ratelimit.h>
+#include <linux/compaction.h>
 #include <linux/hugetlb.h>
 #include <linux/initrd.h>
 #include <linux/key.h>
@@ -52,6 +53,7 @@
 #include <linux/slow-work.h>
 #include <linux/perf_event.h>
 #include <linux/kprobes.h>
+#include <linux/pipe_fs_i.h>
 
 #include <asm/uaccess.h>
 #include <asm/processor.h>
@@ -163,6 +165,27 @@ static int proc_taint(struct ctl_table *table, int write,
                                void __user *buffer, size_t *lenp, loff_t *ppos);
 #endif
 
+#ifdef CONFIG_MAGIC_SYSRQ
+static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
+
+static int sysrq_sysctl_handler(ctl_table *table, int write,
+                                void __user *buffer, size_t *lenp,
+                                loff_t *ppos)
+{
+        int error;
+
+        error = proc_dointvec(table, write, buffer, lenp, ppos);
+        if (error)
+                return error;
+
+        if (write)
+                sysrq_toggle_support(__sysrq_enabled);
+
+        return 0;
+}
+
+#endif
+
 static struct ctl_table root_table[];
 static struct ctl_table_root sysctl_table_root;
 static struct ctl_table_header root_table_header = {
@@ -240,6 +263,11 @@ static int min_sched_shares_ratelimit = 100000; /* 100 usec */
 static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
 #endif
 
+#ifdef CONFIG_COMPACTION
+static int min_extfrag_threshold;
+static int max_extfrag_threshold = 1000;
+#endif
+
 static struct ctl_table kern_table[] = {
         {
                 .procname       = "sched_child_runs_first",
@@ -567,7 +595,7 @@ static struct ctl_table kern_table[] = {
                 .data           = &__sysrq_enabled,
                 .maxlen         = sizeof (int),
                 .mode           = 0644,
-                .proc_handler   = proc_dointvec,
+                .proc_handler   = sysrq_sysctl_handler,
         },
 #endif
 #ifdef CONFIG_PROC_SYSCTL
@@ -621,7 +649,7 @@ static struct ctl_table kern_table[] = {
 #endif
         {
                 .procname       = "userprocess_debug",
-                .data           = &sysctl_userprocess_debug,
+                .data           = &show_unhandled_signals,
                 .maxlen         = sizeof(int),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec,
@@ -1099,6 +1127,25 @@ static struct ctl_table vm_table[] = {
                 .mode           = 0644,
                 .proc_handler   = drop_caches_sysctl_handler,
         },
+#ifdef CONFIG_COMPACTION
+        {
+                .procname       = "compact_memory",
+                .data           = &sysctl_compact_memory,
+                .maxlen         = sizeof(int),
+                .mode           = 0200,
+                .proc_handler   = sysctl_compaction_handler,
+        },
+        {
+                .procname       = "extfrag_threshold",
+                .data           = &sysctl_extfrag_threshold,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = sysctl_extfrag_handler,
+                .extra1         = &min_extfrag_threshold,
+                .extra2         = &max_extfrag_threshold,
+        },
+
+#endif /* CONFIG_COMPACTION */
         {
                 .procname       = "min_free_kbytes",
                 .data           = &min_free_kbytes,
@@ -1423,6 +1470,14 @@ static struct ctl_table fs_table[] = {
                 .child          = binfmt_misc_table,
         },
 #endif
+        {
+                .procname       = "pipe-max-pages",
+                .data           = &pipe_max_pages,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .extra1         = &two,
+        },
 /*
  * NOTE: do not add new entries to this table unless you have read
  * Documentation/sysctl/ctl_unnumbered.txt
@@ -1431,7 +1486,8 @@ static struct ctl_table fs_table[] = {
 };
 
 static struct ctl_table debug_table[] = {
-#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC)
+#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
+    defined(CONFIG_S390)
         {
                 .procname       = "exception-trace",
                 .data           = &show_unhandled_signals,
@@ -2040,8 +2096,132 @@ int proc_dostring(struct ctl_table *table, int write,
                                buffer, lenp, ppos);
 }
 
+static size_t proc_skip_spaces(char **buf)
+{
+        size_t ret;
+        char *tmp = skip_spaces(*buf);
+        ret = tmp - *buf;
+        *buf = tmp;
+        return ret;
+}
+
+static void proc_skip_char(char **buf, size_t *size, const char v)
+{
+        while (*size) {
+                if (**buf != v)
+                        break;
+                (*size)--;
+                (*buf)++;
+        }
+}
+
+#define TMPBUFLEN 22
+/**
+ * proc_get_long - reads an ASCII formatted integer from a user buffer
+ *
+ * @buf: a kernel buffer
+ * @size: size of the kernel buffer
+ * @val: this is where the number will be stored
+ * @neg: set to %TRUE if number is negative
+ * @perm_tr: a vector which contains the allowed trailers
+ * @perm_tr_len: size of the perm_tr vector
+ * @tr: pointer to store the trailer character
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes read. If @tr is non-NULL and a trailing
+ * character exists (size is non-zero after returning from this
+ * function), @tr is updated with the trailing character.
+ */
+static int proc_get_long(char **buf, size_t *size,
+                          unsigned long *val, bool *neg,
+                          const char *perm_tr, unsigned perm_tr_len, char *tr)
+{
+        int len;
+        char *p, tmp[TMPBUFLEN];
+
+        if (!*size)
+                return -EINVAL;
+
+        len = *size;
+        if (len > TMPBUFLEN - 1)
+                len = TMPBUFLEN - 1;
+
+        memcpy(tmp, *buf, len);
+
+        tmp[len] = 0;
+        p = tmp;
+        if (*p == '-' && *size > 1) {
+                *neg = true;
+                p++;
+        } else
+                *neg = false;
+        if (!isdigit(*p))
+                return -EINVAL;
+
+        *val = simple_strtoul(p, &p, 0);
+
+        len = p - tmp;
+
+        /* We don't know if the next char is whitespace thus we may accept
+         * invalid integers (e.g. 1234...a) or two integers instead of one
+         * (e.g. 123...1). So lets not allow such large numbers. */
+        if (len == TMPBUFLEN - 1)
+                return -EINVAL;
+
+        if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
+                return -EINVAL;
+
+        if (tr && (len < *size))
+                *tr = *p;
+
+        *buf += len;
+        *size -= len;
+
+        return 0;
+}
+
+/**
+ * proc_put_long - converts an integer to a decimal ASCII formatted string
+ *
+ * @buf: the user buffer
+ * @size: the size of the user buffer
+ * @val: the integer to be converted
+ * @neg: sign of the number, %TRUE for negative
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes written.
+ */
+static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
+                          bool neg)
+{
+        int len;
+        char tmp[TMPBUFLEN], *p = tmp;
+
+        sprintf(p, "%s%lu", neg ? "-" : "", val);
+        len = strlen(tmp);
+        if (len > *size)
+                len = *size;
+        if (copy_to_user(*buf, tmp, len))
+                return -EFAULT;
+        *size -= len;
+        *buf += len;
+        return 0;
+}
+#undef TMPBUFLEN
+
+static int proc_put_char(void __user **buf, size_t *size, char c)
+{
+        if (*size) {
+                char __user **buffer = (char __user **)buf;
+                if (put_user(c, *buffer))
+                        return -EFAULT;
+                (*size)--, (*buffer)++;
+                *buf = *buffer;
+        }
+        return 0;
+}
 
-static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
                                  int *valp,
                                  int write, void *data)
 {
@@ -2050,33 +2230,31 @@ static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
         } else {
                 int val = *valp;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         *lvalp = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         *lvalp = (unsigned long)val;
                 }
         }
         return 0;
 }
 
+static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
+
 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
                   int write, void __user *buffer,
                   size_t *lenp, loff_t *ppos,
-                  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                               int write, void *data),
                   void *data)
 {
-#define TMPBUFLEN 21
-        int *i, vleft, first = 1, neg;
-        unsigned long lval;
-        size_t left, len;
+        int *i, vleft, first = 1, err = 0;
+        unsigned long page = 0;
+        size_t left;
+        char *kbuf;
         
-        char buf[TMPBUFLEN], *p;
-        char __user *s = buffer;
-        
-        if (!tbl_data || !table->maxlen || !*lenp ||
-            (*ppos && !write)) {
+        if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
                 *lenp = 0;
                 return 0;
         }
@@ -2088,89 +2266,71 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
         if (!conv)
                 conv = do_proc_dointvec_conv;
 
+        if (write) {
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        err = -EFAULT;
+                        goto free;
+                }
+                kbuf[left] = 0;
+        }
+
         for (; left && vleft--; i++, first=0) {
+                unsigned long lval;
+                bool neg;
+
                 if (write) {
-                        while (left) {
-                                char c;
-                                if (get_user(c, s))
-                                        return -EFAULT;
-                                if (!isspace(c))
-                                        break;
-                                left--;
-                                s++;
-                        }
+                        left -= proc_skip_spaces(&kbuf);
+
                         if (!left)
                                 break;
-                        neg = 0;
-                        len = left;
-                        if (len > sizeof(buf) - 1)
-                                len = sizeof(buf) - 1;
-                        if (copy_from_user(buf, s, len))
-                                return -EFAULT;
-                        buf[len] = 0;
-                        p = buf;
-                        if (*p == '-' && left > 1) {
-                                neg = 1;
-                                p++;
-                        }
-                        if (*p < '0' || *p > '9')
+                        err = proc_get_long(&kbuf, &left, &lval, &neg,
+                                             proc_wspace_sep,
+                                             sizeof(proc_wspace_sep), NULL);
+                        if (err)
                                 break;
-
-                        lval = simple_strtoul(p, &p, 0);
-
-                        len = p-buf;
-                        if ((len < left) && *p && !isspace(*p))
-                                break;
-                        s += len;
-                        left -= len;
-
-                        if (conv(&neg, &lval, i, 1, data))
+                        if (conv(&neg, &lval, i, 1, data)) {
+                                err = -EINVAL;
                                 break;
+                        }
                 } else {
-                        p = buf;
+                        if (conv(&neg, &lval, i, 0, data)) {
+                                err = -EINVAL;
+                                break;
+                        }
                         if (!first)
-                                *p++ = '\t';
-        
-                        if (conv(&neg, &lval, i, 0, data))
+                                err = proc_put_char(&buffer, &left, '\t');
+                        if (err)
+                                break;
+                        err = proc_put_long(&buffer, &left, lval, neg);
+                        if (err)
                                 break;
-
-                        sprintf(p, "%s%lu", neg ? "-" : "", lval);
-                        len = strlen(buf);
-                        if (len > left)
-                                len = left;
-                        if(copy_to_user(s, buf, len))
-                                return -EFAULT;
-                        left -= len;
-                        s += len;
                 }
         }
 
-        if (!write && !first && left) {
-                if(put_user('\n', s))
-                        return -EFAULT;
-                left--, s++;
-        }
+        if (!write && !first && left && !err)
+                err = proc_put_char(&buffer, &left, '\n');
+        if (write && !err && left)
+                left -= proc_skip_spaces(&kbuf);
+free:
         if (write) {
-                while (left) {
-                        char c;
-                        if (get_user(c, s++))
-                                return -EFAULT;
-                        if (!isspace(c))
-                                break;
-                        left--;
-                }
+                free_page(page);
+                if (first)
+                        return err ? : -EINVAL;
         }
-        if (write && first)
-                return -EINVAL;
         *lenp -= left;
         *ppos += *lenp;
-        return 0;
-#undef TMPBUFLEN
+        return err;
 }
 
 static int do_proc_dointvec(struct ctl_table *table, int write,
                   void __user *buffer, size_t *lenp, loff_t *ppos,
-                  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                               int write, void *data),
                   void *data)
 {
@@ -2238,8 +2398,8 @@ struct do_proc_dointvec_minmax_conv_param {
         int *max;
 };
 
-static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
-                                        int *valp, 
+static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
+                                        int *valp,
                                         int write, void *data)
 {
         struct do_proc_dointvec_minmax_conv_param *param = data;
@@ -2252,10 +2412,10 @@ static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
         } else {
                 int val = *valp;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         *lvalp = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         *lvalp = (unsigned long)val;
                 }
         }
@@ -2295,102 +2455,78 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
                                      unsigned long convmul,
                                      unsigned long convdiv)
 {
-#define TMPBUFLEN 21
-        unsigned long *i, *min, *max, val;
-        int vleft, first=1, neg;
-        size_t len, left;
-        char buf[TMPBUFLEN], *p;
-        char __user *s = buffer;
-        
-        if (!data || !table->maxlen || !*lenp ||
-            (*ppos && !write)) {
+        unsigned long *i, *min, *max;
+        int vleft, first = 1, err = 0;
+        unsigned long page = 0;
+        size_t left;
+        char *kbuf;
+
+        if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
                 *lenp = 0;
                 return 0;
         }
-        
+
         i = (unsigned long *) data;
         min = (unsigned long *) table->extra1;
         max = (unsigned long *) table->extra2;
         vleft = table->maxlen / sizeof(unsigned long);
         left = *lenp;
-        
+
+        if (write) {
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        err = -EFAULT;
+                        goto free;
+                }
+                kbuf[left] = 0;
+        }
+
         for (; left && vleft--; i++, min++, max++, first=0) {
+                unsigned long val;
+
                 if (write) {
-                        while (left) {
-                                char c;
-                                if (get_user(c, s))
-                                        return -EFAULT;
-                                if (!isspace(c))
-                                        break;
-                                left--;
-                                s++;
-                        }
-                        if (!left)
-                                break;
-                        neg = 0;
-                        len = left;
-                        if (len > TMPBUFLEN-1)
-                                len = TMPBUFLEN-1;
-                        if (copy_from_user(buf, s, len))
-                                return -EFAULT;
-                        buf[len] = 0;
-                        p = buf;
-                        if (*p == '-' && left > 1) {
-                                neg = 1;
-                                p++;
-                        }
-                        if (*p < '0' || *p > '9')
-                                break;
-                        val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
-                        len = p-buf;
-                        if ((len < left) && *p && !isspace(*p))
+                        bool neg;
+
+                        left -= proc_skip_spaces(&kbuf);
+
+                        err = proc_get_long(&kbuf, &left, &val, &neg,
+                                             proc_wspace_sep,
+                                             sizeof(proc_wspace_sep), NULL);
+                        if (err)
                                 break;
                         if (neg)
-                                val = -val;
-                        s += len;
-                        left -= len;
-
-                        if(neg)
                                 continue;
                         if ((min && val < *min) || (max && val > *max))
                                 continue;
                         *i = val;
                 } else {
-                        p = buf;
+                        val = convdiv * (*i) / convmul;
                         if (!first)
-                                *p++ = '\t';
-                        sprintf(p, "%lu", convdiv * (*i) / convmul);
-                        len = strlen(buf);
-                        if (len > left)
-                                len = left;
-                        if(copy_to_user(s, buf, len))
-                                return -EFAULT;
-                        left -= len;
-                        s += len;
+                                err = proc_put_char(&buffer, &left, '\t');
+                        err = proc_put_long(&buffer, &left, val, false);
+                        if (err)
+                                break;
                 }
         }
 
-        if (!write && !first && left) {
-                if(put_user('\n', s))
-                        return -EFAULT;
-                left--, s++;
-        }
+        if (!write && !first && left && !err)
+                err = proc_put_char(&buffer, &left, '\n');
+        if (write && !err)
+                left -= proc_skip_spaces(&kbuf);
+free:
         if (write) {
-                while (left) {
-                        char c;
-                        if (get_user(c, s++))
-                                return -EFAULT;
-                        if (!isspace(c))
-                                break;
-                        left--;
-                }
+                free_page(page);
+                if (first)
+                        return err ? : -EINVAL;
         }
-        if (write && first)
-                return -EINVAL;
         *lenp -= left;
         *ppos += *lenp;
-        return 0;
-#undef TMPBUFLEN
+        return err;
 }
 
 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
@@ -2451,7 +2587,7 @@ int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
 }
 
 
-static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
                                          int *valp,
                                          int write, void *data)
 {
@@ -2463,10 +2599,10 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = lval / HZ;
@@ -2474,7 +2610,7 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
         return 0;
 }
 
-static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
                                                 int *valp,
                                                 int write, void *data)
 {
@@ -2486,10 +2622,10 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = jiffies_to_clock_t(lval);
@@ -2497,7 +2633,7 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
         return 0;
 }
 
-static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
                                             int *valp,
                                             int write, void *data)
 {
@@ -2507,10 +2643,10 @@ static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = jiffies_to_msecs(lval);
@@ -2607,6 +2743,157 @@ static int proc_do_cad_pid(struct ctl_table *table, int write,
         return 0;
 }
 
+/**
+ * proc_do_large_bitmap - read/write from/to a large bitmap
+ * @table: the sysctl table
+ * @write: %TRUE if this is a write to the sysctl file
+ * @buffer: the user buffer
+ * @lenp: the size of the user buffer
+ * @ppos: file position
+ *
+ * The bitmap is stored at table->data and the bitmap length (in bits)
+ * in table->maxlen.
+ *
+ * We use a range comma separated format (e.g. 1,3-4,10-10) so that
+ * large bitmaps may be represented in a compact manner. Writing into
+ * the file will clear the bitmap then update it with the given input.
+ *
+ * Returns 0 on success.
+ */
+int proc_do_large_bitmap(struct ctl_table *table, int write,
+                         void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+        int err = 0;
+        bool first = 1;
+        size_t left = *lenp;
+        unsigned long bitmap_len = table->maxlen;
+        unsigned long *bitmap = (unsigned long *) table->data;
+        unsigned long *tmp_bitmap = NULL;
+        char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
+
+        if (!bitmap_len || !left || (*ppos && !write)) {
+                *lenp = 0;
+                return 0;
+        }
+
+        if (write) {
+                unsigned long page = 0;
+                char *kbuf;
+
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        free_page(page);
+                        return -EFAULT;
+                }
+                kbuf[left] = 0;
+
+                tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
+                                     GFP_KERNEL);
+                if (!tmp_bitmap) {
+                        free_page(page);
+                        return -ENOMEM;
+                }
+                proc_skip_char(&kbuf, &left, '\n');
+                while (!err && left) {
+                        unsigned long val_a, val_b;
+                        bool neg;
+
+                        err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
+                                             sizeof(tr_a), &c);
+                        if (err)
+                                break;
+                        if (val_a >= bitmap_len || neg) {
+                                err = -EINVAL;
+                                break;
+                        }
+
+                        val_b = val_a;
+                        if (left) {
+                                kbuf++;
+                                left--;
+                        }
+
+                        if (c == '-') {
+                                err = proc_get_long(&kbuf, &left, &val_b,
+                                                     &neg, tr_b, sizeof(tr_b),
+                                                     &c);
+                                if (err)
+                                        break;
+                                if (val_b >= bitmap_len || neg ||
+                                    val_a > val_b) {
+                                        err = -EINVAL;
+                                        break;
+                                }
+                                if (left) {
+                                        kbuf++;
+                                        left--;
+                                }
+                        }
+
+                        while (val_a <= val_b)
+                                set_bit(val_a++, tmp_bitmap);
+
+                        first = 0;
+                        proc_skip_char(&kbuf, &left, '\n');
+                }
+                free_page(page);
+        } else {
+                unsigned long bit_a, bit_b = 0;
+
+                while (left) {
+                        bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
+                        if (bit_a >= bitmap_len)
+                                break;
+                        bit_b = find_next_zero_bit(bitmap, bitmap_len,
+                                                   bit_a + 1) - 1;
+
+                        if (!first) {
+                                err = proc_put_char(&buffer, &left, ',');
+                                if (err)
+                                        break;
+                        }
+                        err = proc_put_long(&buffer, &left, bit_a, false);
+                        if (err)
+                                break;
+                        if (bit_a != bit_b) {
+                                err = proc_put_char(&buffer, &left, '-');
+                                if (err)
+                                        break;
+                                err = proc_put_long(&buffer, &left, bit_b, false);
+                                if (err)
+                                        break;
+                        }
+
+                        first = 0; bit_b++;
+                }
+                if (!err)
+                        err = proc_put_char(&buffer, &left, '\n');
+        }
+
+        if (!err) {
+                if (write) {
+                        if (*ppos)
+                                bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
+                        else
+                                memcpy(bitmap, tmp_bitmap,
+                                        BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
+                }
+                kfree(tmp_bitmap);
+                *lenp -= left;
+                *ppos += *lenp;
+                return 0;
+        } else {
+                kfree(tmp_bitmap);
+                return err;
+        }
+}
+
 #else /* CONFIG_PROC_FS */
 
 int proc_dostring(struct ctl_table *table, int write,