Gitweb: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=40ca9fdf8aa7d929e2b8939be1e6380d107381e1 Commit: 40ca9fdf8aa7d929e2b8939be1e6380d107381e1 Parent: 7252374a39d794879f5e47bcfa0a16e7599b27b5 Author: Henrique de Moraes Holschuh <[EMAIL PROTECTED]> AuthorDate: Tue Apr 24 11:48:15 2007 -0300 Committer: Len Brown <[EMAIL PROTECTED]> CommitDate: Wed Apr 25 02:00:27 2007 -0400
ACPI: thinkpad-acpi: protect fan and hotkey data structures Add proper mutex locking to some data structures access subject to races due to concurrent access of driver functions on the hotkey and fan subdrivers. Signed-off-by: Henrique de Moraes Holschuh <[EMAIL PROTECTED]> Signed-off-by: Len Brown <[EMAIL PROTECTED]> --- drivers/misc/thinkpad_acpi.c | 114 ++++++++++++++++++++++++++++++++---------- drivers/misc/thinkpad_acpi.h | 5 ++ 2 files changed, 92 insertions(+), 27 deletions(-) diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c index ca6d15c..aa69ff0 100644 --- a/drivers/misc/thinkpad_acpi.c +++ b/drivers/misc/thinkpad_acpi.c @@ -704,6 +704,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm) vdbg_printk(TPACPI_DBG_INIT, "initializing hotkey subdriver\n"); IBM_ACPIHANDLE_INIT(hkey); + mutex_init(&hotkey_mutex); /* hotkey not supported on 570 */ tp_features.hotkey = hkey_handle != NULL; @@ -752,6 +753,9 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event) } } +/* + * Call with hotkey_mutex held + */ static int hotkey_get(int *status, int *mask) { if (!acpi_evalf(hkey_handle, status, "DHKC", "d")) @@ -764,6 +768,9 @@ static int hotkey_get(int *status, int *mask) return 0; } +/* + * Call with hotkey_mutex held + */ static int hotkey_set(int status, int mask) { int i; @@ -792,7 +799,11 @@ static int hotkey_read(char *p) return len; } + res = mutex_lock_interruptible(&hotkey_mutex); + if (res < 0) + return res; res = hotkey_get(&status, &mask); + mutex_unlock(&hotkey_mutex); if (res) return res; @@ -818,10 +829,15 @@ static int hotkey_write(char *buf) if (!tp_features.hotkey) return -ENODEV; + res = mutex_lock_interruptible(&hotkey_mutex); + if (res < 0) + return res; + res = hotkey_get(&status, &mask); if (res) - return res; + goto errexit; + res = 0; while ((cmd = next_cmd(&buf))) { if (strlencmp(cmd, "enable") == 0) { status = 1; @@ -834,18 +850,19 @@ static int hotkey_write(char *buf) /* mask set */ } else if (sscanf(cmd, "%x", &mask) == 1) { /* mask set */ - } else - return -EINVAL; + } else { + res = -EINVAL; + goto errexit; + } do_cmd = 1; } - if (do_cmd) { + if (do_cmd) res = hotkey_set(status, mask); - if (res) - return res; - } - return 0; +errexit: + mutex_unlock(&hotkey_mutex); + return res; } static struct tp_acpi_drv_struct ibm_hotkey_acpidriver = { @@ -2575,6 +2592,7 @@ static int __init fan_init(struct ibm_init_struct *iibm) { vdbg_printk(TPACPI_DBG_INIT, "initializing fan subdriver\n"); + mutex_init(&fan_mutex); fan_status_access_mode = TPACPI_FAN_NONE; fan_control_access_mode = TPACPI_FAN_WR_NONE; fan_control_commands = 0; @@ -2764,10 +2782,17 @@ static void fan_watchdog_reset(void) static int fan_set_level(int level) { + int res; + switch (fan_control_access_mode) { case TPACPI_FAN_WR_ACPI_SFAN: if (level >= 0 && level <= 7) { - if (!acpi_evalf(sfan_handle, NULL, NULL, "vd", level)) + res = mutex_lock_interruptible(&fan_mutex); + if (res < 0) + return res; + res = acpi_evalf(sfan_handle, NULL, NULL, "vd", level); + mutex_unlock(&fan_mutex); + if (!res) return -EIO; } else return -EINVAL; @@ -2780,7 +2805,12 @@ static int fan_set_level(int level) ((level < 0) || (level > 7))) return -EINVAL; - if (!acpi_ec_write(fan_status_offset, level)) + res = mutex_lock_interruptible(&fan_mutex); + if (res < 0) + return res; + res = acpi_ec_write(fan_status_offset, level); + mutex_unlock(&fan_mutex); + if (!res) return -EIO; else tp_features.fan_ctrl_status_undef = 0; @@ -2797,25 +2827,33 @@ static int fan_set_enable(void) u8 s; int rc; + rc = mutex_lock_interruptible(&fan_mutex); + if (rc < 0) + return rc; + switch (fan_control_access_mode) { case TPACPI_FAN_WR_ACPI_FANS: case TPACPI_FAN_WR_TPEC: - if ((rc = fan_get_status(&s)) < 0) - return rc; + rc = fan_get_status(&s); + if (rc < 0) + break; /* Don't go out of emergency fan mode */ if (s != 7) s = TP_EC_FAN_AUTO; if (!acpi_ec_write(fan_status_offset, s)) - return -EIO; - else + rc = -EIO; + else { tp_features.fan_ctrl_status_undef = 0; + rc = 0; + } break; case TPACPI_FAN_WR_ACPI_SFAN: - if ((rc = fan_get_status(&s)) < 0) - return rc; + rc = fan_get_status(&s); + if (rc < 0) + break; s &= 0x07; @@ -2824,53 +2862,75 @@ static int fan_set_enable(void) s = 4; if (!acpi_evalf(sfan_handle, NULL, NULL, "vd", s)) - return -EIO; + rc= -EIO; + else + rc = 0; break; default: - return -ENXIO; + rc = -ENXIO; } - return 0; + + mutex_unlock(&fan_mutex); + return rc; } static int fan_set_disable(void) { + int rc; + + rc = mutex_lock_interruptible(&fan_mutex); + if (rc < 0) + return rc; + + rc = 0; switch (fan_control_access_mode) { case TPACPI_FAN_WR_ACPI_FANS: case TPACPI_FAN_WR_TPEC: if (!acpi_ec_write(fan_status_offset, 0x00)) - return -EIO; + rc = -EIO; else tp_features.fan_ctrl_status_undef = 0; break; case TPACPI_FAN_WR_ACPI_SFAN: if (!acpi_evalf(sfan_handle, NULL, NULL, "vd", 0x00)) - return -EIO; + rc = -EIO; break; default: - return -ENXIO; + rc = -ENXIO; } - return 0; + + mutex_unlock(&fan_mutex); + return rc; } static int fan_set_speed(int speed) { + int rc; + + rc = mutex_lock_interruptible(&fan_mutex); + if (rc < 0) + return rc; + + rc = 0; switch (fan_control_access_mode) { case TPACPI_FAN_WR_ACPI_FANS: if (speed >= 0 && speed <= 65535) { if (!acpi_evalf(fans_handle, NULL, NULL, "vddd", speed, speed, speed)) - return -EIO; + rc = -EIO; } else - return -EINVAL; + rc = -EINVAL; break; default: - return -ENXIO; + rc = -ENXIO; } - return 0; + + mutex_unlock(&fan_mutex); + return rc; } static int fan_read(char *p) diff --git a/drivers/misc/thinkpad_acpi.h b/drivers/misc/thinkpad_acpi.h index 84fdefe..a9feb53 100644 --- a/drivers/misc/thinkpad_acpi.h +++ b/drivers/misc/thinkpad_acpi.h @@ -30,6 +30,7 @@ #include <linux/types.h> #include <linux/string.h> #include <linux/list.h> +#include <linux/mutex.h> #include <linux/proc_fs.h> #include <linux/sysfs.h> @@ -375,6 +376,8 @@ static enum fan_control_commands fan_control_commands; static u8 fan_control_initial_status; static int fan_watchdog_maxinterval; +struct mutex fan_mutex; + static acpi_handle fans_handle, gfan_handle, sfan_handle; static int fan_init(struct ibm_init_struct *iibm); @@ -403,6 +406,8 @@ static int fan_write_cmd_watchdog(const char *cmd, int *rc); static int hotkey_orig_status; static int hotkey_orig_mask; +static struct mutex hotkey_mutex; + static int hotkey_init(struct ibm_init_struct *iibm); static void hotkey_exit(void); static int hotkey_get(int *status, int *mask); - To unsubscribe from this list: send the line "unsubscribe git-commits-head" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html