From 26d1c80fd61e59d5e2eb6fda00e0148a6704ddeb Mon Sep 17 00:00:00 2001 From: Xiaoming Ni Date: Fri, 21 Jan 2022 22:12:38 -0800 Subject: [PATCH] scsi/sg: move sg-big-buff sysctl to scsi/sg.c kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain. To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic. So move the sg-big-buff sysctl from kernel/sysctl.c to drivers/scsi/sg.c and use register_sysctl() to register the sysctl interface. [mcgrof@kernel.org: commit log update] Link: https://lkml.kernel.org/r/20211124231435.1445213-7-mcgrof@kernel.org Signed-off-by: Xiaoming Ni Signed-off-by: Luis Chamberlain Cc: Al Viro Cc: Amir Goldstein Cc: Andy Shevchenko Cc: Antti Palosaari Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Benjamin LaHaise Cc: Clemens Ladisch Cc: David Airlie Cc: Douglas Gilbert Cc: Eric Biederman Cc: Greg Kroah-Hartman Cc: Iurii Zaikin Cc: James E.J. Bottomley Cc: Jani Nikula Cc: Jani Nikula Cc: Jan Kara Cc: Joel Becker Cc: John Ogness Cc: Joonas Lahtinen Cc: Joseph Qi Cc: Julia Lawall Cc: Kees Cook Cc: Lukas Middendorf Cc: Mark Fasheh Cc: Martin K. Petersen Cc: Paul Turner Cc: Peter Zijlstra Cc: Petr Mladek Cc: Phillip Potter Cc: Qing Wang Cc: "Rafael J. Wysocki" Cc: Rodrigo Vivi Cc: Sebastian Reichel Cc: Sergey Senozhatsky Cc: Stephen Kitt Cc: Steven Rostedt (VMware) Cc: Suren Baghdasaryan Cc: Tetsuo Handa Cc: "Theodore Ts'o" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/scsi/sg.c | 35 ++++++++++++++++++++++++++++++++++- include/scsi/sg.h | 4 ---- kernel/sysctl.c | 12 ------------ 3 files changed, 34 insertions(+), 17 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index ad12b3261845..6b43e97bd417 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -77,7 +77,7 @@ static int sg_proc_init(void); #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) -int sg_big_buff = SG_DEF_RESERVED_SIZE; +static int sg_big_buff = SG_DEF_RESERVED_SIZE; /* N.B. This variable is readable and writeable via /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer of this size (or less if there is not enough memory) will be reserved @@ -1634,6 +1634,37 @@ MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); +#ifdef CONFIG_SYSCTL +#include + +static struct ctl_table sg_sysctls[] = { + { + .procname = "sg-big-buff", + .data = &sg_big_buff, + .maxlen = sizeof(int), + .mode = 0444, + .proc_handler = proc_dointvec, + }, + {} +}; + +static struct ctl_table_header *hdr; +static void register_sg_sysctls(void) +{ + if (!hdr) + hdr = register_sysctl("kernel", sg_sysctls); +} + +static void unregister_sg_sysctls(void) +{ + if (hdr) + unregister_sysctl_table(hdr); +} +#else +#define register_sg_sysctls() do { } while (0) +#define unregister_sg_sysctls() do { } while (0) +#endif /* CONFIG_SYSCTL */ + static int __init init_sg(void) { @@ -1666,6 +1697,7 @@ init_sg(void) return 0; } class_destroy(sg_sysfs_class); + register_sg_sysctls(); err_out: unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); return rc; @@ -1674,6 +1706,7 @@ err_out: static void __exit exit_sg(void) { + unregister_sg_sysctls(); #ifdef CONFIG_SCSI_PROC_FS remove_proc_subtree("scsi/sg", NULL); #endif /* CONFIG_SCSI_PROC_FS */ diff --git a/include/scsi/sg.h b/include/scsi/sg.h index 843cefb8efce..068e35d36557 100644 --- a/include/scsi/sg.h +++ b/include/scsi/sg.h @@ -29,10 +29,6 @@ * For utility and test programs see: http://sg.danny.cz/sg/sg3_utils.html */ -#ifdef __KERNEL__ -extern int sg_big_buff; /* for sysctl */ -#endif - typedef struct sg_iovec /* same structure as used by readv() Linux system */ { /* call. It defines one scatter-gather element. */ diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 509f782483db..b0cced3808d4 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -95,9 +95,6 @@ #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT) #include #endif -#ifdef CONFIG_CHR_DEV_SG -#include -#endif #ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE #include #endif @@ -2090,15 +2087,6 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dostring, }, #endif -#ifdef CONFIG_CHR_DEV_SG - { - .procname = "sg-big-buff", - .data = &sg_big_buff, - .maxlen = sizeof (int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, -#endif #ifdef CONFIG_BSD_PROCESS_ACCT { .procname = "acct",