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author | Jia He <hejianet@gmail.com> | 2021-08-03 12:59:36 +0200 |
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committer | Chuck Lever <chuck.lever@oracle.com> | 2021-08-17 11:47:53 -0400 |
commit | a2071573d6346819cc4e5787b4206f2184985160 (patch) | |
tree | 29b4e98e0d31a6e0e2516595818769c216f5e9bb | |
parent | 5c11720767f70d34357d00a15ba5a0ad052c40fe (diff) | |
download | linux-a2071573d6346819cc4e5787b4206f2184985160.tar.gz linux-a2071573d6346819cc4e5787b4206f2184985160.tar.bz2 linux-a2071573d6346819cc4e5787b4206f2184985160.zip |
sysctl: introduce new proc handler proc_dobool
This is to let bool variable could be correctly displayed in
big/little endian sysctl procfs. sizeof(bool) is arch dependent,
proc_dobool should work in all arches.
Suggested-by: Pan Xinhui <xinhui@linux.vnet.ibm.com>
Signed-off-by: Jia He <hejianet@gmail.com>
[thuth: rebased the patch to the current kernel version]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
-rw-r--r-- | include/linux/sysctl.h | 2 | ||||
-rw-r--r-- | kernel/sysctl.c | 42 |
2 files changed, 44 insertions, 0 deletions
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index d99ca99837de..1fa2b69c6fc3 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -48,6 +48,8 @@ typedef int proc_handler(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos); int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *); +int proc_dobool(struct ctl_table *table, int write, void *buffer, + size_t *lenp, loff_t *ppos); int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 272f4a272f8c..25e49b4d8049 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -536,6 +536,21 @@ static void proc_put_char(void **buf, size_t *size, char c) } } +static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp, + int *valp, + int write, void *data) +{ + if (write) { + *(bool *)valp = *lvalp; + } else { + int val = *(bool *)valp; + + *lvalp = (unsigned long)val; + *negp = false; + } + return 0; +} + static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp, int *valp, int write, void *data) @@ -799,6 +814,26 @@ static int do_proc_douintvec(struct ctl_table *table, int write, } /** + * proc_dobool - read/write a bool + * @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 + * + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer + * values from/to the user buffer, treated as an ASCII string. + * + * Returns 0 on success. + */ +int proc_dobool(struct ctl_table *table, int write, void *buffer, + size_t *lenp, loff_t *ppos) +{ + return do_proc_dointvec(table, write, buffer, lenp, ppos, + do_proc_dobool_conv, NULL); +} + +/** * proc_dointvec - read a vector of integers * @table: the sysctl table * @write: %TRUE if this is a write to the sysctl file @@ -1630,6 +1665,12 @@ int proc_dostring(struct ctl_table *table, int write, return -ENOSYS; } +int proc_dobool(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + return -ENOSYS; +} + int proc_dointvec(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { @@ -3425,6 +3466,7 @@ int __init sysctl_init(void) * No sense putting this after each symbol definition, twice, * exception granted :-) */ +EXPORT_SYMBOL(proc_dobool); EXPORT_SYMBOL(proc_dointvec); EXPORT_SYMBOL(proc_douintvec); EXPORT_SYMBOL(proc_dointvec_jiffies); |