From: Paolo 'Blaisorblade' Giarrusso Date: Tue, 31 Oct 2006 06:07:07 +0000 (-0800) Subject: [PATCH] uml ubd driver: change ubd_lock to be a mutex X-Git-Tag: v2.6.19-rc5~119 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=d7fb2c3865ca0f95d92e2864c3dc9220789d83f5;p=linux-2.6-omap-h63xx.git [PATCH] uml ubd driver: change ubd_lock to be a mutex This lock protects ubd setup and teardown, so is only used in process context; beyond that, during such setup memory allocations must be performed and some generic functions which can sleep must be called (such as add_disk()). So the only correct solution is to make it a mutex instead of a spin_lock. No other change is done - this lock must be acquired in different places but it's done afterwards. Signed-off-by: Paolo 'Blaisorblade' Giarrusso Cc: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c index cdd82e89618..a3061ae39b3 100644 --- a/arch/um/drivers/ubd_kern.c +++ b/arch/um/drivers/ubd_kern.c @@ -107,7 +107,8 @@ static inline void ubd_set_bit(__u64 bit, unsigned char *data) #define DRIVER_NAME "uml-blkdev" static DEFINE_SPINLOCK(ubd_io_lock); -static DEFINE_SPINLOCK(ubd_lock); + +static DEFINE_MUTEX(ubd_lock); static void (*do_ubd)(void); @@ -314,7 +315,7 @@ static int ubd_setup_common(char *str, int *index_out) } err = 1; - spin_lock(&ubd_lock); + mutex_lock(&ubd_lock); if(fake_major != MAJOR_NR){ printk(KERN_ERR "Can't assign a fake major twice\n"); goto out1; @@ -326,7 +327,7 @@ static int ubd_setup_common(char *str, int *index_out) major); err = 0; out1: - spin_unlock(&ubd_lock); + mutex_unlock(&ubd_lock); return(err); } @@ -343,7 +344,7 @@ static int ubd_setup_common(char *str, int *index_out) } err = 1; - spin_lock(&ubd_lock); + mutex_lock(&ubd_lock); ubd_dev = &ubd_devs[n]; if(ubd_dev->file != NULL){ @@ -405,7 +406,7 @@ break_loop: ubd_dev->cow.file = backing_file; ubd_dev->boot_openflags = flags; out: - spin_unlock(&ubd_lock); + mutex_unlock(&ubd_lock); return(err); } @@ -710,11 +711,11 @@ static int ubd_config(char *str) } if(n == -1) return(0); - spin_lock(&ubd_lock); + mutex_lock(&ubd_lock); err = ubd_add(n); if(err) ubd_devs[n].file = NULL; - spin_unlock(&ubd_lock); + mutex_unlock(&ubd_lock); return(err); } @@ -731,7 +732,7 @@ static int ubd_get_config(char *name, char *str, int size, char **error_out) } ubd_dev = &ubd_devs[n]; - spin_lock(&ubd_lock); + mutex_lock(&ubd_lock); if(ubd_dev->file == NULL){ CONFIG_CHUNK(str, size, len, "", 1); @@ -747,7 +748,7 @@ static int ubd_get_config(char *name, char *str, int size, char **error_out) else CONFIG_CHUNK(str, size, len, "", 1); out: - spin_unlock(&ubd_lock); + mutex_unlock(&ubd_lock); return(len); } @@ -766,7 +767,7 @@ static int ubd_remove(int n) struct ubd *ubd_dev; int err = -ENODEV; - spin_lock(&ubd_lock); + mutex_lock(&ubd_lock); if(ubd_gendisk[n] == NULL) goto out; @@ -795,7 +796,7 @@ static int ubd_remove(int n) *ubd_dev = ((struct ubd) DEFAULT_UBD); err = 0; out: - spin_unlock(&ubd_lock); + mutex_unlock(&ubd_lock); return err; }