The patch titled
sysctl: factor out sysctl_head_next from do_sysctl
has been removed from the -mm tree. Its filename was
sysctl-factor-out-sysctl_head_next-from-do_sysctl.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: sysctl: factor out sysctl_head_next from do_sysctl
From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
The current logic to walk through the list of sysctl table headers is slightly
painful and implement in a way it cannot be used by code outside sysctl.c
I am in the process of implementing a version of the sysctl proc support that
instead of using the proc generic non-caching monster, just uses the existing
sysctl data structure as backing store for building the dcache entries and for
doing directory reads. To use the existing data structures however I need a
way to get at them.
[akpm@xxxxxxxx: warning fix]
Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/sysctl.h | 4 ++
kernel/sysctl.c | 60 +++++++++++++++++++++++++++------------
2 files changed, 47 insertions(+), 17 deletions(-)
diff -puN include/linux/sysctl.h~sysctl-factor-out-sysctl_head_next-from-do_sysctl include/linux/sysctl.h
--- a/include/linux/sysctl.h~sysctl-factor-out-sysctl_head_next-from-do_sysctl
+++ a/include/linux/sysctl.h
@@ -924,6 +924,10 @@ enum
#ifdef __KERNEL__
#include <linux/list.h>
+/* For the /proc/sys support */
+extern struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev);
+extern void sysctl_head_finish(struct ctl_table_header *prev);
+
extern void sysctl_init(void);
typedef struct ctl_table ctl_table;
diff -puN kernel/sysctl.c~sysctl-factor-out-sysctl_head_next-from-do_sysctl kernel/sysctl.c
--- a/kernel/sysctl.c~sysctl-factor-out-sysctl_head_next-from-do_sysctl
+++ a/kernel/sysctl.c
@@ -1070,6 +1070,42 @@ static void start_unregistering(struct c
list_del_init(&p->ctl_entry);
}
+void sysctl_head_finish(struct ctl_table_header *head)
+{
+ if (!head)
+ return;
+ spin_lock(&sysctl_lock);
+ unuse_table(head);
+ spin_unlock(&sysctl_lock);
+}
+
+struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
+{
+ struct ctl_table_header *head;
+ struct list_head *tmp;
+ spin_lock(&sysctl_lock);
+ if (prev) {
+ tmp = &prev->ctl_entry;
+ unuse_table(prev);
+ goto next;
+ }
+ tmp = &root_table_header.ctl_entry;
+ for (;;) {
+ head = list_entry(tmp, struct ctl_table_header, ctl_entry);
+
+ if (!use_table(head))
+ goto next;
+ spin_unlock(&sysctl_lock);
+ return head;
+ next:
+ tmp = tmp->next;
+ if (tmp == &root_table_header.ctl_entry)
+ break;
+ }
+ spin_unlock(&sysctl_lock);
+ return NULL;
+}
+
void __init sysctl_init(void)
{
#ifdef CONFIG_PROC_SYSCTL
@@ -1081,7 +1117,7 @@ void __init sysctl_init(void)
int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
- struct list_head *tmp;
+ struct ctl_table_header *head;
int error = -ENOTDIR;
if (nlen <= 0 || nlen >= CTL_MAXNAME)
@@ -1091,26 +1127,16 @@ int do_sysctl(int __user *name, int nlen
if (!oldlenp || get_user(old_len, oldlenp))
return -EFAULT;
}
- spin_lock(&sysctl_lock);
- tmp = &root_table_header.ctl_entry;
- do {
- struct ctl_table_header *head =
- list_entry(tmp, struct ctl_table_header, ctl_entry);
-
- if (!use_table(head))
- continue;
-
- spin_unlock(&sysctl_lock);
+ for (head = sysctl_head_next(NULL); head;
+ head = sysctl_head_next(head)) {
error = parse_table(name, nlen, oldval, oldlenp,
newval, newlen, head->ctl_table);
-
- spin_lock(&sysctl_lock);
- unuse_table(head);
- if (error != -ENOTDIR)
+ if (error != -ENOTDIR) {
+ sysctl_head_finish(head);
break;
- } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
- spin_unlock(&sysctl_lock);
+ }
+ }
return error;
}
_
Patches currently in -mm which might be from ebiederm@xxxxxxxxxxxx are
origin.patch
powerpc-rtas-msi-support.patch
fix-i-oat-for-kexec.patch
git-v9fs.patch
x86_64-irq-simplfy-__assign_irq_vector.patch
x86_64-irq-handle-irqs-pending-in-irr-during-irq-migration.patch
procfs-fix-race-between-proc_readdir-and-remove_proc_entry.patch
procfs-fix-race-between-proc_readdir-and-remove_proc_entry-fix.patch
clone-flag-clone_parent_tidptr-leaves-invalid-results-in-memory.patch
fix-rmmod-read-write-races-in-proc-entries.patch
fix-rmmod-read-write-races-in-proc-entries-fix.patch
allow-access-to-proc-pid-fd-after-setuid.patch
allow-access-to-proc-pid-fd-after-setuid-fix.patch
allow-access-to-proc-pid-fd-after-setuid-update.patch
allow-access-to-proc-pid-fd-after-setuid-update-2.patch
shm-make-sysv-ipc-shared-memory-use-stacked-files.patch
i386-apic-clean-up-the-apic-code.patch
i386-rework-local-apic-timer-calibration.patch
i386-prepare-nmi-watchdog-for-dynticks.patch
edac-k8-driver-coding-tidy.patch
sched2-sched-domain-sysctl-use-ctl_unnumbered.patch
mm-implement-swap-prefetching-use-ctl_unnumbered.patch
readahead-sysctl-parameters-use-ctl_unnumbered.patch
sysctl-remove-insert_at_head-from-register_sysctl-fix.patch
vdso-print-fatal-signals-use-ctl_unnumbered.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
