From akpm@osdl.org Mon Feb 6 14:10:39 2006 Message-Id: <200602062210.k16MAa5X031577@shell0.pdx.osdl.net> Subject: kobj_map semaphore to mutex conversion To: jes@sgi.com, greg@kroah.com, mm-commits@vger.kernel.org From: akpm@osdl.org Date: Mon, 6 Feb 2006 14:12:43 -0800 From: Jes Sorensen Convert the kobj_map code to use a mutex instead of a semaphore. It converts the single two users as well, genhd.c and char_dev.c. Signed-off-by: Jes Sorensen Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- block/genhd.c | 31 ++++++++++++++++--------------- drivers/base/map.c | 21 +++++++++++---------- fs/char_dev.c | 17 +++++++++-------- include/linux/kobj_map.h | 4 ++-- 4 files changed, 38 insertions(+), 35 deletions(-) --- gregkh-2.6.orig/block/genhd.c +++ gregkh-2.6/block/genhd.c @@ -15,12 +15,13 @@ #include #include #include +#include #define MAX_PROBE_HASH 255 /* random */ static struct subsystem block_subsys; -static DECLARE_MUTEX(block_subsys_sem); +static DEFINE_MUTEX(block_subsys_lock); /* * Can be deleted altogether. Later. @@ -46,7 +47,7 @@ struct blkdev_info { /* * iterate over a list of blkdev_info structures. allows * the major_names array to be iterated over from outside this file - * must be called with the block_subsys_sem held + * must be called with the block_subsys_lock held */ void *get_next_blkdev(void *dev) { @@ -85,20 +86,20 @@ out: void *acquire_blkdev_list(void) { - down(&block_subsys_sem); + mutex_lock(&block_subsys_lock); return get_next_blkdev(NULL); } void release_blkdev_list(void *dev) { - up(&block_subsys_sem); + mutex_unlock(&block_subsys_lock); kfree(dev); } /* * Count the number of records in the blkdev_list. - * must be called with the block_subsys_sem held + * must be called with the block_subsys_lock held */ int count_blkdev_list(void) { @@ -118,7 +119,7 @@ int count_blkdev_list(void) /* * extract the major and name values from a blkdev_info struct * passed in as a void to *dev. Must be called with - * block_subsys_sem held + * block_subsys_lock held */ int get_blkdev_info(void *dev, int *major, char **name) { @@ -138,7 +139,7 @@ int register_blkdev(unsigned int major, struct blk_major_name **n, *p; int index, ret = 0; - down(&block_subsys_sem); + mutex_lock(&block_subsys_lock); /* temporary */ if (major == 0) { @@ -183,7 +184,7 @@ int register_blkdev(unsigned int major, kfree(p); } out: - up(&block_subsys_sem); + mutex_unlock(&block_subsys_lock); return ret; } @@ -197,7 +198,7 @@ int unregister_blkdev(unsigned int major int index = major_to_index(major); int ret = 0; - down(&block_subsys_sem); + mutex_lock(&block_subsys_lock); for (n = &major_names[index]; *n; n = &(*n)->next) if ((*n)->major == major) break; @@ -207,7 +208,7 @@ int unregister_blkdev(unsigned int major p = *n; *n = p->next; } - up(&block_subsys_sem); + mutex_unlock(&block_subsys_lock); kfree(p); return ret; @@ -301,7 +302,7 @@ static void *part_start(struct seq_file struct list_head *p; loff_t l = *pos; - down(&block_subsys_sem); + mutex_lock(&block_subsys_lock); list_for_each(p, &block_subsys.kset.list) if (!l--) return list_entry(p, struct gendisk, kobj.entry); @@ -318,7 +319,7 @@ static void *part_next(struct seq_file * static void part_stop(struct seq_file *part, void *v) { - up(&block_subsys_sem); + mutex_unlock(&block_subsys_lock); } static int show_partition(struct seq_file *part, void *v) @@ -377,7 +378,7 @@ static struct kobject *base_probe(dev_t static int __init genhd_device_init(void) { - bdev_map = kobj_map_init(base_probe, &block_subsys_sem); + bdev_map = kobj_map_init(base_probe, &block_subsys_lock); blk_dev_init(); subsystem_register(&block_subsys); return 0; @@ -611,7 +612,7 @@ static void *diskstats_start(struct seq_ loff_t k = *pos; struct list_head *p; - down(&block_subsys_sem); + mutex_lock(&block_subsys_lock); list_for_each(p, &block_subsys.kset.list) if (!k--) return list_entry(p, struct gendisk, kobj.entry); @@ -628,7 +629,7 @@ static void *diskstats_next(struct seq_f static void diskstats_stop(struct seq_file *part, void *v) { - up(&block_subsys_sem); + mutex_unlock(&block_subsys_lock); } static int diskstats_show(struct seq_file *s, void *v) --- gregkh-2.6.orig/drivers/base/map.c +++ gregkh-2.6/drivers/base/map.c @@ -11,6 +11,7 @@ #include #include +#include #include #include #include @@ -25,7 +26,7 @@ struct kobj_map { int (*lock)(dev_t, void *); void *data; } *probes[255]; - struct semaphore *sem; + struct mutex *lock; }; int kobj_map(struct kobj_map *domain, dev_t dev, unsigned long range, @@ -53,7 +54,7 @@ int kobj_map(struct kobj_map *domain, de p->range = range; p->data = data; } - down(domain->sem); + mutex_lock(domain->lock); for (i = 0, p -= n; i < n; i++, p++, index++) { struct probe **s = &domain->probes[index % 255]; while (*s && (*s)->range < range) @@ -61,7 +62,7 @@ int kobj_map(struct kobj_map *domain, de p->next = *s; *s = p; } - up(domain->sem); + mutex_unlock(domain->lock); return 0; } @@ -75,7 +76,7 @@ void kobj_unmap(struct kobj_map *domain, if (n > 255) n = 255; - down(domain->sem); + mutex_lock(domain->lock); for (i = 0; i < n; i++, index++) { struct probe **s; for (s = &domain->probes[index % 255]; *s; s = &(*s)->next) { @@ -88,7 +89,7 @@ void kobj_unmap(struct kobj_map *domain, } } } - up(domain->sem); + mutex_unlock(domain->lock); kfree(found); } @@ -99,7 +100,7 @@ struct kobject *kobj_lookup(struct kobj_ unsigned long best = ~0UL; retry: - down(domain->sem); + mutex_lock(domain->lock); for (p = domain->probes[MAJOR(dev) % 255]; p; p = p->next) { struct kobject *(*probe)(dev_t, int *, void *); struct module *owner; @@ -120,7 +121,7 @@ retry: module_put(owner); continue; } - up(domain->sem); + mutex_unlock(domain->lock); kobj = probe(dev, index, data); /* Currently ->owner protects _only_ ->probe() itself. */ module_put(owner); @@ -128,11 +129,11 @@ retry: return kobj; goto retry; } - up(domain->sem); + mutex_unlock(domain->lock); return NULL; } -struct kobj_map *kobj_map_init(kobj_probe_t *base_probe, struct semaphore *sem) +struct kobj_map *kobj_map_init(kobj_probe_t *base_probe, struct mutex *lock) { struct kobj_map *p = kmalloc(sizeof(struct kobj_map), GFP_KERNEL); struct probe *base = kzalloc(sizeof(*base), GFP_KERNEL); @@ -149,6 +150,6 @@ struct kobj_map *kobj_map_init(kobj_prob base->get = base_probe; for (i = 0; i < 255; i++) p->probes[i] = base; - p->sem = sem; + p->lock = lock; return p; } --- gregkh-2.6.orig/fs/char_dev.c +++ gregkh-2.6/fs/char_dev.c @@ -19,6 +19,7 @@ #include #include #include +#include #ifdef CONFIG_KMOD #include @@ -28,7 +29,7 @@ static struct kobj_map *cdev_map; #define MAX_PROBE_HASH 255 /* random */ -static DECLARE_MUTEX(chrdevs_lock); +static DEFINE_MUTEX(chrdevs_lock); static struct char_device_struct { struct char_device_struct *next; @@ -88,13 +89,13 @@ out: void *acquire_chrdev_list(void) { - down(&chrdevs_lock); + mutex_lock(&chrdevs_lock); return get_next_chrdev(NULL); } void release_chrdev_list(void *dev) { - up(&chrdevs_lock); + mutex_unlock(&chrdevs_lock); kfree(dev); } @@ -151,7 +152,7 @@ __register_chrdev_region(unsigned int ma memset(cd, 0, sizeof(struct char_device_struct)); - down(&chrdevs_lock); + mutex_lock(&chrdevs_lock); /* temporary */ if (major == 0) { @@ -186,10 +187,10 @@ __register_chrdev_region(unsigned int ma } cd->next = *cp; *cp = cd; - up(&chrdevs_lock); + mutex_unlock(&chrdevs_lock); return cd; out: - up(&chrdevs_lock); + mutex_unlock(&chrdevs_lock); kfree(cd); return ERR_PTR(ret); } @@ -200,7 +201,7 @@ __unregister_chrdev_region(unsigned majo struct char_device_struct *cd = NULL, **cp; int i = major_to_index(major); - down(&chrdevs_lock); + mutex_lock(&chrdevs_lock); for (cp = &chrdevs[i]; *cp; cp = &(*cp)->next) if ((*cp)->major == major && (*cp)->baseminor == baseminor && @@ -210,7 +211,7 @@ __unregister_chrdev_region(unsigned majo cd = *cp; *cp = cd->next; } - up(&chrdevs_lock); + mutex_unlock(&chrdevs_lock); return cd; } --- gregkh-2.6.orig/include/linux/kobj_map.h +++ gregkh-2.6/include/linux/kobj_map.h @@ -1,6 +1,6 @@ #ifdef __KERNEL__ -#include +#include typedef struct kobject *kobj_probe_t(dev_t, int *, void *); struct kobj_map; @@ -9,6 +9,6 @@ int kobj_map(struct kobj_map *, dev_t, u kobj_probe_t *, int (*)(dev_t, void *), void *); void kobj_unmap(struct kobj_map *, dev_t, unsigned long); struct kobject *kobj_lookup(struct kobj_map *, dev_t, int *); -struct kobj_map *kobj_map_init(kobj_probe_t *, struct semaphore *); +struct kobj_map *kobj_map_init(kobj_probe_t *, struct mutex *); #endif