From 9c27847dda9cfae7c273cde62becf364f9fa9ea3 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Wed, 27 May 2015 11:09:38 +0930 Subject: kernel/params: constify struct kernel_param_ops uses Most code already uses consts for the struct kernel_param_ops, sweep the kernel for the last offending stragglers. Other than include/linux/moduleparam.h and kernel/params.c all other changes were generated with the following Coccinelle SmPL patch. Merge conflicts between trees can be handled with Coccinelle. In the future git could get Coccinelle merge support to deal with patch --> fail --> grammar --> Coccinelle --> new patch conflicts automatically for us on patches where the grammar is available and the patch is of high confidence. Consider this a feature request. Test compiled on x86_64 against: * allnoconfig * allmodconfig * allyesconfig @ const_found @ identifier ops; @@ const struct kernel_param_ops ops = { }; @ const_not_found depends on !const_found @ identifier ops; @@ -struct kernel_param_ops ops = { +const struct kernel_param_ops ops = { }; Generated-by: Coccinelle SmPL Cc: Rusty Russell Cc: Junio C Hamano Cc: Andrew Morton Cc: Kees Cook Cc: Tejun Heo Cc: Ingo Molnar Cc: cocci@systeme.lip6.fr Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez Signed-off-by: Rusty Russell --- drivers/block/null_blk.c | 4 ++-- drivers/char/ipmi/ipmi_watchdog.c | 6 +++--- drivers/dma/dmatest.c | 4 ++-- drivers/ide/ide.c | 2 +- drivers/infiniband/ulp/srp/ib_srp.c | 4 ++-- drivers/input/misc/ati_remote2.c | 4 ++-- drivers/input/mouse/psmouse-base.c | 2 +- drivers/misc/lis3lv02d/lis3lv02d.c | 2 +- drivers/mtd/ubi/block.c | 2 +- drivers/net/wireless/ath/wil6210/main.c | 4 ++-- drivers/power/test_power.c | 16 ++++++++-------- drivers/thermal/intel_powerclamp.c | 4 ++-- drivers/tty/hvc/hvc_iucv.c | 2 +- drivers/tty/sysrq.c | 2 +- drivers/video/fbdev/uvesafb.c | 2 +- drivers/virtio/virtio_mmio.c | 2 +- 16 files changed, 31 insertions(+), 31 deletions(-) (limited to 'drivers') diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index 65cd61a4145e..0b4b25617bb7 100644 --- a/drivers/block/null_blk.c +++ b/drivers/block/null_blk.c @@ -99,7 +99,7 @@ static int null_set_queue_mode(const char *str, const struct kernel_param *kp) return null_param_store_val(str, &queue_mode, NULL_Q_BIO, NULL_Q_MQ); } -static struct kernel_param_ops null_queue_mode_param_ops = { +static const struct kernel_param_ops null_queue_mode_param_ops = { .set = null_set_queue_mode, .get = param_get_int, }; @@ -127,7 +127,7 @@ static int null_set_irqmode(const char *str, const struct kernel_param *kp) NULL_IRQ_TIMER); } -static struct kernel_param_ops null_irqmode_param_ops = { +static const struct kernel_param_ops null_irqmode_param_ops = { .set = null_set_irqmode, .get = param_get_int, }; diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c index 37b8be7cba95..0ac3bd1a5497 100644 --- a/drivers/char/ipmi/ipmi_watchdog.c +++ b/drivers/char/ipmi/ipmi_watchdog.c @@ -208,7 +208,7 @@ static int set_param_timeout(const char *val, const struct kernel_param *kp) return rv; } -static struct kernel_param_ops param_ops_timeout = { +static const struct kernel_param_ops param_ops_timeout = { .set = set_param_timeout, .get = param_get_int, }; @@ -270,14 +270,14 @@ static int set_param_wdog_ifnum(const char *val, const struct kernel_param *kp) return 0; } -static struct kernel_param_ops param_ops_wdog_ifnum = { +static const struct kernel_param_ops param_ops_wdog_ifnum = { .set = set_param_wdog_ifnum, .get = param_get_int, }; #define param_check_wdog_ifnum param_check_int -static struct kernel_param_ops param_ops_str = { +static const struct kernel_param_ops param_ops_str = { .set = set_param_str, .get = get_param_str, }; diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index 220ee49633e4..b8576fd6bd0e 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -120,7 +120,7 @@ static struct dmatest_info { static int dmatest_run_set(const char *val, const struct kernel_param *kp); static int dmatest_run_get(char *val, const struct kernel_param *kp); -static struct kernel_param_ops run_ops = { +static const struct kernel_param_ops run_ops = { .set = dmatest_run_set, .get = dmatest_run_get, }; @@ -195,7 +195,7 @@ static int dmatest_wait_get(char *val, const struct kernel_param *kp) return param_get_bool(val, kp); } -static struct kernel_param_ops wait_ops = { +static const struct kernel_param_ops wait_ops = { .get = dmatest_wait_get, .set = param_set_bool, }; diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c index e29b02ca9e91..f086ef387475 100644 --- a/drivers/ide/ide.c +++ b/drivers/ide/ide.c @@ -199,7 +199,7 @@ static int ide_set_dev_param_mask(const char *s, const struct kernel_param *kp) return 0; } -static struct kernel_param_ops param_ops_ide_dev_mask = { +static const struct kernel_param_ops param_ops_ide_dev_mask = { .set = ide_set_dev_param_mask }; diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 918814cd0f80..e4eec9da5ea9 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -98,7 +98,7 @@ module_param(register_always, bool, 0444); MODULE_PARM_DESC(register_always, "Use memory registration even for contiguous memory regions"); -static struct kernel_param_ops srp_tmo_ops; +static const struct kernel_param_ops srp_tmo_ops; static int srp_reconnect_delay = 10; module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay, @@ -183,7 +183,7 @@ out: return res; } -static struct kernel_param_ops srp_tmo_ops = { +static const struct kernel_param_ops srp_tmo_ops = { .get = srp_tmo_get, .set = srp_tmo_set, }; diff --git a/drivers/input/misc/ati_remote2.c b/drivers/input/misc/ati_remote2.c index f63341f20b91..cfd58e87da26 100644 --- a/drivers/input/misc/ati_remote2.c +++ b/drivers/input/misc/ati_remote2.c @@ -94,7 +94,7 @@ static int ati_remote2_get_mode_mask(char *buffer, static unsigned int channel_mask = ATI_REMOTE2_MAX_CHANNEL_MASK; #define param_check_channel_mask(name, p) __param_check(name, p, unsigned int) -static struct kernel_param_ops param_ops_channel_mask = { +static const struct kernel_param_ops param_ops_channel_mask = { .set = ati_remote2_set_channel_mask, .get = ati_remote2_get_channel_mask, }; @@ -103,7 +103,7 @@ MODULE_PARM_DESC(channel_mask, "Bitmask of channels to accept <15:Channel16>...< static unsigned int mode_mask = ATI_REMOTE2_MAX_MODE_MASK; #define param_check_mode_mask(name, p) __param_check(name, p, unsigned int) -static struct kernel_param_ops param_ops_mode_mask = { +static const struct kernel_param_ops param_ops_mode_mask = { .set = ati_remote2_set_mode_mask, .get = ati_remote2_get_mode_mask, }; diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c index 5bb1658f60c7..f8286b625ec4 100644 --- a/drivers/input/mouse/psmouse-base.c +++ b/drivers/input/mouse/psmouse-base.c @@ -47,7 +47,7 @@ MODULE_LICENSE("GPL"); static unsigned int psmouse_max_proto = PSMOUSE_AUTO; static int psmouse_set_maxproto(const char *val, const struct kernel_param *); static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp); -static struct kernel_param_ops param_ops_proto_abbrev = { +static const struct kernel_param_ops param_ops_proto_abbrev = { .set = psmouse_set_maxproto, .get = psmouse_get_maxproto, }; diff --git a/drivers/misc/lis3lv02d/lis3lv02d.c b/drivers/misc/lis3lv02d/lis3lv02d.c index 4739689d23ad..fb8705fc3aca 100644 --- a/drivers/misc/lis3lv02d/lis3lv02d.c +++ b/drivers/misc/lis3lv02d/lis3lv02d.c @@ -115,7 +115,7 @@ static int param_set_axis(const char *val, const struct kernel_param *kp) return ret; } -static struct kernel_param_ops param_ops_axis = { +static const struct kernel_param_ops param_ops_axis = { .set = param_set_axis, .get = param_get_int, }; diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c index c9eb78f10a0d..4968c071f399 100644 --- a/drivers/mtd/ubi/block.c +++ b/drivers/mtd/ubi/block.c @@ -161,7 +161,7 @@ static int __init ubiblock_set_param(const char *val, return 0; } -static struct kernel_param_ops ubiblock_param_ops = { +static const struct kernel_param_ops ubiblock_param_ops = { .set = ubiblock_set_param, }; module_param_cb(block, &ubiblock_param_ops, NULL, 0); diff --git a/drivers/net/wireless/ath/wil6210/main.c b/drivers/net/wireless/ath/wil6210/main.c index c2a238426425..790c3df0bb03 100644 --- a/drivers/net/wireless/ath/wil6210/main.c +++ b/drivers/net/wireless/ath/wil6210/main.c @@ -58,7 +58,7 @@ static int mtu_max_set(const char *val, const struct kernel_param *kp) return ret; } -static struct kernel_param_ops mtu_max_ops = { +static const struct kernel_param_ops mtu_max_ops = { .set = mtu_max_set, .get = param_get_uint, }; @@ -87,7 +87,7 @@ static int ring_order_set(const char *val, const struct kernel_param *kp) return 0; } -static struct kernel_param_ops ring_order_ops = { +static const struct kernel_param_ops ring_order_ops = { .set = ring_order_set, .get = param_get_uint, }; diff --git a/drivers/power/test_power.c b/drivers/power/test_power.c index f986e0cca7ac..83c42ea88f2b 100644 --- a/drivers/power/test_power.c +++ b/drivers/power/test_power.c @@ -448,42 +448,42 @@ static int param_set_battery_voltage(const char *key, #define param_get_battery_voltage param_get_int -static struct kernel_param_ops param_ops_ac_online = { +static const struct kernel_param_ops param_ops_ac_online = { .set = param_set_ac_online, .get = param_get_ac_online, }; -static struct kernel_param_ops param_ops_usb_online = { +static const struct kernel_param_ops param_ops_usb_online = { .set = param_set_usb_online, .get = param_get_usb_online, }; -static struct kernel_param_ops param_ops_battery_status = { +static const struct kernel_param_ops param_ops_battery_status = { .set = param_set_battery_status, .get = param_get_battery_status, }; -static struct kernel_param_ops param_ops_battery_present = { +static const struct kernel_param_ops param_ops_battery_present = { .set = param_set_battery_present, .get = param_get_battery_present, }; -static struct kernel_param_ops param_ops_battery_technology = { +static const struct kernel_param_ops param_ops_battery_technology = { .set = param_set_battery_technology, .get = param_get_battery_technology, }; -static struct kernel_param_ops param_ops_battery_health = { +static const struct kernel_param_ops param_ops_battery_health = { .set = param_set_battery_health, .get = param_get_battery_health, }; -static struct kernel_param_ops param_ops_battery_capacity = { +static const struct kernel_param_ops param_ops_battery_capacity = { .set = param_set_battery_capacity, .get = param_get_battery_capacity, }; -static struct kernel_param_ops param_ops_battery_voltage = { +static const struct kernel_param_ops param_ops_battery_voltage = { .set = param_set_battery_voltage, .get = param_get_battery_voltage, }; diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c index 725718e97a0b..500f8f551817 100644 --- a/drivers/thermal/intel_powerclamp.c +++ b/drivers/thermal/intel_powerclamp.c @@ -119,7 +119,7 @@ exit: return ret; } -static struct kernel_param_ops duration_ops = { +static const struct kernel_param_ops duration_ops = { .set = duration_set, .get = param_get_int, }; @@ -167,7 +167,7 @@ exit_win: return ret; } -static struct kernel_param_ops window_size_ops = { +static const struct kernel_param_ops window_size_ops = { .set = window_size_set, .get = param_get_int, }; diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c index f78a87b07872..bb809cf36617 100644 --- a/drivers/tty/hvc/hvc_iucv.c +++ b/drivers/tty/hvc/hvc_iucv.c @@ -1345,7 +1345,7 @@ static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp) #define param_check_vmidfilter(name, p) __param_check(name, p, void) -static struct kernel_param_ops param_ops_vmidfilter = { +static const struct kernel_param_ops param_ops_vmidfilter = { .set = param_set_vmidfilter, .get = param_get_vmidfilter, }; diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index 843f2cdc280b..03b02c37d247 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -1002,7 +1002,7 @@ static int sysrq_reset_seq_param_set(const char *buffer, return 0; } -static struct kernel_param_ops param_ops_sysrq_reset_seq = { +static const struct kernel_param_ops param_ops_sysrq_reset_seq = { .get = param_get_ushort, .set = sysrq_reset_seq_param_set, }; diff --git a/drivers/video/fbdev/uvesafb.c b/drivers/video/fbdev/uvesafb.c index d32d1c4d1b99..178ae93b7ebd 100644 --- a/drivers/video/fbdev/uvesafb.c +++ b/drivers/video/fbdev/uvesafb.c @@ -1977,7 +1977,7 @@ static int param_set_scroll(const char *val, const struct kernel_param *kp) return 0; } -static struct kernel_param_ops param_ops_scroll = { +static const struct kernel_param_ops param_ops_scroll = { .set = param_set_scroll, }; #define param_check_scroll(name, p) __param_check(name, p, void) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 7a5e60dea6c5..10189b5b627f 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -691,7 +691,7 @@ static int vm_cmdline_get(char *buffer, const struct kernel_param *kp) return strlen(buffer) + 1; } -static struct kernel_param_ops vm_cmdline_param_ops = { +static const struct kernel_param_ops vm_cmdline_param_ops = { .set = vm_cmdline_set, .get = vm_cmdline_get, }; -- cgit v1.2.3 From b51d23e4e9fea6f264d39535c2a62d1f51e7ccc3 Mon Sep 17 00:00:00 2001 From: Dan Streetman Date: Wed, 17 Jun 2015 06:18:52 +0930 Subject: module: add per-module param_lock Add a "param_lock" mutex to each module, and update params.c to use the correct built-in or module mutex while locking kernel params. Remove the kparam_block_sysfs_r/w() macros, replace them with direct calls to kernel_param_[un]lock(module). The kernel param code currently uses a single mutex to protect modification of any and all kernel params. While this generally works, there is one specific problem with it; a module callback function cannot safely load another module, i.e. with request_module() or even with indirect calls such as crypto_has_alg(). If the module to be loaded has any of its params configured (e.g. with a /etc/modprobe.d/* config file), then the attempt will result in a deadlock between the first module param callback waiting for modprobe, and modprobe trying to lock the single kernel param mutex to set the new module's param. This fixes that by using per-module mutexes, so that each individual module is protected against concurrent changes in its own kernel params, but is not blocked by changes to other module params. All built-in modules continue to use the built-in mutex, since they will always be loaded at runtime and references (e.g. request_module(), crypto_has_alg()) to them will never cause load-time param changing. This also simplifies the interface used by modules to block sysfs access to their params; while there are currently functions to block and unblock sysfs param access which are split up by read and write and expect a single kernel param to be passed, their actual operation is identical and applies to all params, not just the one passed to them; they simply lock and unlock the global param mutex. They are replaced with direct calls to kernel_param_[un]lock(THIS_MODULE), which locks THIS_MODULE's param_lock, or if the module is built-in, it locks the built-in mutex. Suggested-by: Rusty Russell Signed-off-by: Dan Streetman Signed-off-by: Rusty Russell --- arch/um/drivers/hostaudio_kern.c | 20 ++++---- drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 6 +-- drivers/net/wireless/libertas_tf/if_usb.c | 6 +-- drivers/usb/atm/ueagle-atm.c | 4 +- drivers/video/fbdev/vt8623fb.c | 4 +- include/linux/module.h | 1 + include/linux/moduleparam.h | 61 ++++-------------------- kernel/module.c | 2 + kernel/params.c | 50 +++++++++++-------- net/mac80211/rate.c | 4 +- 10 files changed, 65 insertions(+), 93 deletions(-) (limited to 'drivers') diff --git a/arch/um/drivers/hostaudio_kern.c b/arch/um/drivers/hostaudio_kern.c index 9b90fdc4b151..f6b911cc3923 100644 --- a/arch/um/drivers/hostaudio_kern.c +++ b/arch/um/drivers/hostaudio_kern.c @@ -185,9 +185,9 @@ static int hostaudio_open(struct inode *inode, struct file *file) int ret; #ifdef DEBUG - kparam_block_sysfs_write(dsp); + kernel_param_lock(THIS_MODULE); printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp); - kparam_unblock_sysfs_write(dsp); + kernel_param_unlock(THIS_MODULE); #endif state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL); @@ -199,11 +199,11 @@ static int hostaudio_open(struct inode *inode, struct file *file) if (file->f_mode & FMODE_WRITE) w = 1; - kparam_block_sysfs_write(dsp); + kernel_param_lock(THIS_MODULE); mutex_lock(&hostaudio_mutex); ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0); mutex_unlock(&hostaudio_mutex); - kparam_unblock_sysfs_write(dsp); + kernel_param_unlock(THIS_MODULE); if (ret < 0) { kfree(state); @@ -260,17 +260,17 @@ static int hostmixer_open_mixdev(struct inode *inode, struct file *file) if (file->f_mode & FMODE_WRITE) w = 1; - kparam_block_sysfs_write(mixer); + kernel_param_lock(THIS_MODULE); mutex_lock(&hostaudio_mutex); ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0); mutex_unlock(&hostaudio_mutex); - kparam_unblock_sysfs_write(mixer); + kernel_param_unlock(THIS_MODULE); if (ret < 0) { - kparam_block_sysfs_write(dsp); + kernel_param_lock(THIS_MODULE); printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', " "err = %d\n", dsp, -ret); - kparam_unblock_sysfs_write(dsp); + kernel_param_unlock(THIS_MODULE); kfree(state); return ret; } @@ -326,10 +326,10 @@ MODULE_LICENSE("GPL"); static int __init hostaudio_init_module(void) { - __kernel_param_lock(); + kernel_param_lock(THIS_MODULE); printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n", dsp, mixer); - __kernel_param_unlock(); + kernel_param_unlock(THIS_MODULE); module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1); if (module_data.dev_audio < 0) { diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c index 2bae50292dcd..83651ac8ddb9 100644 --- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c +++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c @@ -279,7 +279,7 @@ MODULE_FIRMWARE("myri10ge_eth_z8e.dat"); MODULE_FIRMWARE("myri10ge_rss_ethp_z8e.dat"); MODULE_FIRMWARE("myri10ge_rss_eth_z8e.dat"); -/* Careful: must be accessed under kparam_block_sysfs_write */ +/* Careful: must be accessed under kernel_param_lock() */ static char *myri10ge_fw_name = NULL; module_param(myri10ge_fw_name, charp, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(myri10ge_fw_name, "Firmware image name"); @@ -3427,7 +3427,7 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp) } } - kparam_block_sysfs_write(myri10ge_fw_name); + kernel_param_lock(THIS_MODULE); if (myri10ge_fw_name != NULL) { char *fw_name = kstrdup(myri10ge_fw_name, GFP_KERNEL); if (fw_name) { @@ -3435,7 +3435,7 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp) set_fw_name(mgp, fw_name, true); } } - kparam_unblock_sysfs_write(myri10ge_fw_name); + kernel_param_unlock(THIS_MODULE); if (mgp->board_number < MYRI10GE_MAX_BOARDS && myri10ge_fw_names[mgp->board_number] != NULL && diff --git a/drivers/net/wireless/libertas_tf/if_usb.c b/drivers/net/wireless/libertas_tf/if_usb.c index 1a20cee5febe..799a2efe5793 100644 --- a/drivers/net/wireless/libertas_tf/if_usb.c +++ b/drivers/net/wireless/libertas_tf/if_usb.c @@ -821,15 +821,15 @@ static int if_usb_prog_firmware(struct if_usb_card *cardp) lbtf_deb_enter(LBTF_DEB_USB); - kparam_block_sysfs_write(fw_name); + kernel_param_lock(THIS_MODULE); ret = request_firmware(&cardp->fw, lbtf_fw_name, &cardp->udev->dev); if (ret < 0) { pr_err("request_firmware() failed with %#x\n", ret); pr_err("firmware %s not found\n", lbtf_fw_name); - kparam_unblock_sysfs_write(fw_name); + kernel_param_unlock(THIS_MODULE); goto done; } - kparam_unblock_sysfs_write(fw_name); + kernel_param_unlock(THIS_MODULE); if (check_fwfile_format(cardp->fw->data, cardp->fw->size)) goto release_fw; diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c index 888998a7fe31..a2ae88dbda78 100644 --- a/drivers/usb/atm/ueagle-atm.c +++ b/drivers/usb/atm/ueagle-atm.c @@ -1599,7 +1599,7 @@ static void cmvs_file_name(struct uea_softc *sc, char *const cmv_name, int ver) char file_arr[] = "CMVxy.bin"; char *file; - kparam_block_sysfs_write(cmv_file); + kernel_param_lock(THIS_MODULE); /* set proper name corresponding modem version and line type */ if (cmv_file[sc->modem_index] == NULL) { if (UEA_CHIP_VERSION(sc) == ADI930) @@ -1618,7 +1618,7 @@ static void cmvs_file_name(struct uea_softc *sc, char *const cmv_name, int ver) strlcat(cmv_name, file, UEA_FW_NAME_MAX); if (ver == 2) strlcat(cmv_name, ".v2", UEA_FW_NAME_MAX); - kparam_unblock_sysfs_write(cmv_file); + kernel_param_unlock(THIS_MODULE); } static int request_cmvs_old(struct uea_softc *sc, diff --git a/drivers/video/fbdev/vt8623fb.c b/drivers/video/fbdev/vt8623fb.c index ea7f056ed5fe..8bac309c24b9 100644 --- a/drivers/video/fbdev/vt8623fb.c +++ b/drivers/video/fbdev/vt8623fb.c @@ -754,9 +754,9 @@ static int vt8623_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) /* Prepare startup mode */ - kparam_block_sysfs_write(mode_option); + kernel_param_lock(THIS_MODULE); rc = fb_find_mode(&(info->var), info, mode_option, NULL, 0, NULL, 8); - kparam_unblock_sysfs_write(mode_option); + kernel_param_unlock(THIS_MODULE); if (! ((rc == 1) || (rc == 2))) { rc = -EINVAL; dev_err(info->device, "mode %s not found\n", mode_option); diff --git a/include/linux/module.h b/include/linux/module.h index 4c1b02e1361d..6ba0e87fa804 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -240,6 +240,7 @@ struct module { unsigned int num_syms; /* Kernel parameters. */ + struct mutex param_lock; struct kernel_param *kp; unsigned int num_kp; diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index ab5031453807..f1fdc50520d8 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -67,6 +67,7 @@ enum { struct kernel_param { const char *name; + struct module *mod; const struct kernel_param_ops *ops; const u16 perm; s8 level; @@ -108,7 +109,7 @@ struct kparam_array * * @perm is 0 if the the variable is not to appear in sysfs, or 0444 * for world-readable, 0644 for root-writable, etc. Note that if it - * is writable, you may need to use kparam_block_sysfs_write() around + * is writable, you may need to use kernel_param_lock() around * accesses (esp. charp, which can be kfreed when it changes). * * The @type is simply pasted to refer to a param_ops_##type and a @@ -216,12 +217,12 @@ struct kparam_array parameters. */ #define __module_param_call(prefix, name, ops, arg, perm, level, flags) \ /* Default value instead of permissions? */ \ - static const char __param_str_##name[] = prefix #name; \ + static const char __param_str_##name[] = prefix #name; \ static struct kernel_param __moduleparam_const __param_##name \ __used \ __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \ - = { __param_str_##name, ops, VERIFY_OCTAL_PERMISSIONS(perm), \ - level, flags, { arg } } + = { __param_str_##name, THIS_MODULE, ops, \ + VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } } /* Obsolete - use module_param_cb() */ #define module_param_call(name, set, get, arg, perm) \ @@ -238,58 +239,14 @@ __check_old_set_param(int (*oldset)(const char *, struct kernel_param *)) return 0; } -/** - * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs. - * @name: the name of the parameter - * - * There's no point blocking write on a paramter that isn't writable via sysfs! - */ -#define kparam_block_sysfs_write(name) \ - do { \ - BUG_ON(!(__param_##name.perm & 0222)); \ - __kernel_param_lock(); \ - } while (0) - -/** - * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again. - * @name: the name of the parameter - */ -#define kparam_unblock_sysfs_write(name) \ - do { \ - BUG_ON(!(__param_##name.perm & 0222)); \ - __kernel_param_unlock(); \ - } while (0) - -/** - * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs. - * @name: the name of the parameter - * - * This also blocks sysfs writes. - */ -#define kparam_block_sysfs_read(name) \ - do { \ - BUG_ON(!(__param_##name.perm & 0444)); \ - __kernel_param_lock(); \ - } while (0) - -/** - * kparam_unblock_sysfs_read - allows sysfs to read a parameter again. - * @name: the name of the parameter - */ -#define kparam_unblock_sysfs_read(name) \ - do { \ - BUG_ON(!(__param_##name.perm & 0444)); \ - __kernel_param_unlock(); \ - } while (0) - #ifdef CONFIG_SYSFS -extern void __kernel_param_lock(void); -extern void __kernel_param_unlock(void); +extern void kernel_param_lock(struct module *mod); +extern void kernel_param_unlock(struct module *mod); #else -static inline void __kernel_param_lock(void) +static inline void kernel_param_lock(struct module *mod) { } -static inline void __kernel_param_unlock(void) +static inline void kernel_param_unlock(struct module *mod) { } #endif diff --git a/kernel/module.c b/kernel/module.c index 427b99f1a4b3..8ec33ce202a6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3442,6 +3442,8 @@ static int load_module(struct load_info *info, const char __user *uargs, if (err) goto unlink_mod; + mutex_init(&mod->param_lock); + /* Now we've got everything in the final locations, we can * find optional sections. */ err = find_module_sections(mod, info); diff --git a/kernel/params.c b/kernel/params.c index a8b09f6c87dc..8890d0b8dffc 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -25,15 +25,20 @@ #include #include -/* Protects all parameters, and incidentally kmalloced_param list. */ +/* Protects all built-in parameters, modules use their own param_lock */ static DEFINE_MUTEX(param_lock); +/* Use the module's mutex, or if built-in use the built-in mutex */ +#define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : ¶m_lock) +#define KPARAM_IS_LOCKED(mod) mutex_is_locked(KPARAM_MUTEX(mod)) + /* This just allows us to keep track of which parameters are kmalloced. */ struct kmalloced_param { struct list_head list; char val[]; }; static LIST_HEAD(kmalloced_params); +static DEFINE_SPINLOCK(kmalloced_params_lock); static void *kmalloc_parameter(unsigned int size) { @@ -43,7 +48,10 @@ static void *kmalloc_parameter(unsigned int size) if (!p) return NULL; + spin_lock(&kmalloced_params_lock); list_add(&p->list, &kmalloced_params); + spin_unlock(&kmalloced_params_lock); + return p->val; } @@ -52,6 +60,7 @@ static void maybe_kfree_parameter(void *param) { struct kmalloced_param *p; + spin_lock(&kmalloced_params_lock); list_for_each_entry(p, &kmalloced_params, list) { if (p->val == param) { list_del(&p->list); @@ -59,6 +68,7 @@ static void maybe_kfree_parameter(void *param) break; } } + spin_unlock(&kmalloced_params_lock); } static char dash2underscore(char c) @@ -118,10 +128,10 @@ static int parse_one(char *param, return -EINVAL; pr_debug("handling %s with %p\n", param, params[i].ops->set); - mutex_lock(¶m_lock); + kernel_param_lock(params[i].mod); param_check_unsafe(¶ms[i]); err = params[i].ops->set(val, ¶ms[i]); - mutex_unlock(¶m_lock); + kernel_param_unlock(params[i].mod); return err; } } @@ -417,7 +427,8 @@ const struct kernel_param_ops param_ops_bint = { EXPORT_SYMBOL(param_ops_bint); /* We break the rule and mangle the string. */ -static int param_array(const char *name, +static int param_array(struct module *mod, + const char *name, const char *val, unsigned int min, unsigned int max, void *elem, int elemsize, @@ -448,7 +459,7 @@ static int param_array(const char *name, /* nul-terminate and parse */ save = val[len]; ((char *)val)[len] = '\0'; - BUG_ON(!mutex_is_locked(¶m_lock)); + BUG_ON(!KPARAM_IS_LOCKED(mod)); ret = set(val, &kp); if (ret != 0) @@ -470,7 +481,7 @@ static int param_array_set(const char *val, const struct kernel_param *kp) const struct kparam_array *arr = kp->arr; unsigned int temp_num; - return param_array(kp->name, val, 1, arr->max, arr->elem, + return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem, arr->elemsize, arr->ops->set, kp->level, arr->num ?: &temp_num); } @@ -485,7 +496,7 @@ static int param_array_get(char *buffer, const struct kernel_param *kp) if (i) buffer[off++] = ','; p.arg = arr->elem + arr->elemsize * i; - BUG_ON(!mutex_is_locked(¶m_lock)); + BUG_ON(!KPARAM_IS_LOCKED(p.mod)); ret = arr->ops->get(buffer + off, &p); if (ret < 0) return ret; @@ -568,9 +579,9 @@ static ssize_t param_attr_show(struct module_attribute *mattr, if (!attribute->param->ops->get) return -EPERM; - mutex_lock(¶m_lock); + kernel_param_lock(mk->mod); count = attribute->param->ops->get(buf, attribute->param); - mutex_unlock(¶m_lock); + kernel_param_unlock(mk->mod); if (count > 0) { strcat(buf, "\n"); ++count; @@ -580,7 +591,7 @@ static ssize_t param_attr_show(struct module_attribute *mattr, /* sysfs always hands a nul-terminated string in buf. We rely on that. */ static ssize_t param_attr_store(struct module_attribute *mattr, - struct module_kobject *km, + struct module_kobject *mk, const char *buf, size_t len) { int err; @@ -589,10 +600,10 @@ static ssize_t param_attr_store(struct module_attribute *mattr, if (!attribute->param->ops->set) return -EPERM; - mutex_lock(¶m_lock); + kernel_param_lock(mk->mod); param_check_unsafe(attribute->param); err = attribute->param->ops->set(buf, attribute->param); - mutex_unlock(¶m_lock); + kernel_param_unlock(mk->mod); if (!err) return len; return err; @@ -605,18 +616,19 @@ static ssize_t param_attr_store(struct module_attribute *mattr, #define __modinit __init #endif -#ifdef CONFIG_SYSFS -void __kernel_param_lock(void) +void kernel_param_lock(struct module *mod) { - mutex_lock(¶m_lock); + mutex_lock(KPARAM_MUTEX(mod)); } -EXPORT_SYMBOL(__kernel_param_lock); -void __kernel_param_unlock(void) +void kernel_param_unlock(struct module *mod) { - mutex_unlock(¶m_lock); + mutex_unlock(KPARAM_MUTEX(mod)); } -EXPORT_SYMBOL(__kernel_param_unlock); + +#ifdef CONFIG_SYSFS +EXPORT_SYMBOL(kernel_param_lock); +EXPORT_SYMBOL(kernel_param_unlock); /* * add_sysfs_param - add a parameter to sysfs diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c index d53355b011f5..8544e2eb570e 100644 --- a/net/mac80211/rate.c +++ b/net/mac80211/rate.c @@ -103,7 +103,7 @@ ieee80211_rate_control_ops_get(const char *name) const struct rate_control_ops *ops; const char *alg_name; - kparam_block_sysfs_write(ieee80211_default_rc_algo); + kernel_param_lock(THIS_MODULE); if (!name) alg_name = ieee80211_default_rc_algo; else @@ -117,7 +117,7 @@ ieee80211_rate_control_ops_get(const char *name) /* try built-in one if specific alg requested but not found */ if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT)) ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT); - kparam_unblock_sysfs_write(ieee80211_default_rc_algo); + kernel_param_unlock(THIS_MODULE); return ops; } -- cgit v1.2.3