diff options
Diffstat (limited to 'kernel/sysctl.c')
| -rw-r--r-- | kernel/sysctl.c | 613 |
1 files changed, 450 insertions, 163 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 04bcd8abe09c..6f79c7f81c96 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> @@ -167,6 +169,27 @@ 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 = { @@ -244,6 +267,11 @@ 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", @@ -571,7 +599,7 @@ 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 @@ -625,7 +653,7 @@ 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, @@ -1110,6 +1138,25 @@ 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, @@ -1434,6 +1481,14 @@ static struct ctl_table fs_table[] = { .child = binfmt_misc_table, }, #endif + { + .procname = "pipe-max-size", + .data = &pipe_max_size, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &pipe_proc_fn, + .extra1 = &pipe_min_size, + }, /* * NOTE: do not add new entries to this table unless you have read * Documentation/sysctl/ctl_unnumbered.txt @@ -1442,7 +1497,8 @@ 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, @@ -2051,8 +2107,132 @@ 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) { @@ -2061,33 +2241,31 @@ 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; } @@ -2099,89 +2277,71 @@ 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) { @@ -2249,8 +2409,8 @@ 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; @@ -2263,10 +2423,10 @@ 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; } } @@ -2306,102 +2466,78 @@ 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, @@ -2462,7 +2598,7 @@ 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) { @@ -2474,10 +2610,10 @@ 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; @@ -2485,7 +2621,7 @@ 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) { @@ -2497,10 +2633,10 @@ 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); @@ -2508,7 +2644,7 @@ 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) { @@ -2518,10 +2654,10 @@ 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); @@ -2618,6 +2754,157 @@ 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, |