From f7eb12c626d4375faf03039261546bd19c1325fd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 28 Nov 2007 10:46:22 -0800 Subject: [PATCH] kobject: convert hvcs to use kref, not kobject hvcs is using a kobject only for reference counting, nothing else. So switch it to use a kref instead, which is all that is needed, and is much smaller. Cc: Anton Blanchard Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Ryan S. Arnold Cc: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- drivers/char/hvcs.c | 78 +++++++++++++++++------------------------------------ 1 file changed, 25 insertions(+), 53 deletions(-) diff --git a/drivers/char/hvcs.c b/drivers/char/hvcs.c index 69d8866..fd75590 100644 --- a/drivers/char/hvcs.c +++ b/drivers/char/hvcs.c @@ -57,11 +57,7 @@ * rescanning partner information upon a user's request. * * Each vty-server, prior to being exposed to this driver is reference counted - * using the 2.6 Linux kernel kobject construct. This kobject is also used by - * the vio bus to provide a vio device sysfs entry that this driver attaches - * device specific attributes to, including partner information. The vio bus - * framework also provides a sysfs entry for each vio driver. The hvcs driver - * provides driver attributes in this entry. + * using the 2.6 Linux kernel kref construct. * * For direction on installation and usage of this driver please reference * Documentation/powerpc/hvcs.txt. @@ -71,7 +67,7 @@ #include #include #include -#include +#include #include #include #include @@ -293,12 +289,12 @@ struct hvcs_struct { int chars_in_buffer; /* - * Any variable below the kobject is valid before a tty is connected and + * Any variable below the kref is valid before a tty is connected and * stays valid after the tty is disconnected. These shouldn't be * whacked until the koject refcount reaches zero though some entries * may be changed via sysfs initiatives. */ - struct kobject kobj; /* ref count & hvcs_struct lifetime */ + struct kref kref; /* ref count & hvcs_struct lifetime */ int connected; /* is the vty-server currently connected to a vty? */ uint32_t p_unit_address; /* partner unit address */ uint32_t p_partition_ID; /* partner partition ID */ @@ -307,8 +303,8 @@ struct hvcs_struct { struct vio_dev *vdev; }; -/* Required to back map a kobject to its containing object */ -#define from_kobj(kobj) container_of(kobj, struct hvcs_struct, kobj) +/* Required to back map a kref to its containing object */ +#define from_kref(k) container_of(k, struct hvcs_struct, kref) static struct list_head hvcs_structs = LIST_HEAD_INIT(hvcs_structs); static DEFINE_SPINLOCK(hvcs_structs_lock); @@ -334,7 +330,6 @@ static void hvcs_partner_free(struct hvcs_struct *hvcsd); static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, unsigned int irq, struct vio_dev *dev); -static void destroy_hvcs_struct(struct kobject *kobj); static int hvcs_open(struct tty_struct *tty, struct file *filp); static void hvcs_close(struct tty_struct *tty, struct file *filp); static void hvcs_hangup(struct tty_struct * tty); @@ -703,10 +698,10 @@ static void hvcs_return_index(int index) hvcs_index_list[index] = -1; } -/* callback when the kboject ref count reaches zero */ -static void destroy_hvcs_struct(struct kobject *kobj) +/* callback when the kref ref count reaches zero */ +static void destroy_hvcs_struct(struct kref *kref) { - struct hvcs_struct *hvcsd = from_kobj(kobj); + struct hvcs_struct *hvcsd = from_kref(kref); struct vio_dev *vdev; unsigned long flags; @@ -743,10 +738,6 @@ static void destroy_hvcs_struct(struct kobject *kobj) kfree(hvcsd); } -static struct kobj_type hvcs_kobj_type = { - .release = destroy_hvcs_struct, -}; - static int hvcs_get_index(void) { int i; @@ -791,9 +782,7 @@ static int __devinit hvcs_probe( spin_lock_init(&hvcsd->lock); /* Automatically incs the refcount the first time */ - kobject_init(&hvcsd->kobj); - /* Set up the callback for terminating the hvcs_struct's life */ - hvcsd->kobj.ktype = &hvcs_kobj_type; + kref_init(&hvcsd->kref); hvcsd->vdev = dev; dev->dev.driver_data = hvcsd; @@ -844,7 +833,6 @@ static int __devexit hvcs_remove(struct vio_dev *dev) { struct hvcs_struct *hvcsd = dev->dev.driver_data; unsigned long flags; - struct kobject *kobjp; struct tty_struct *tty; if (!hvcsd) @@ -856,15 +844,13 @@ static int __devexit hvcs_remove(struct vio_dev *dev) tty = hvcsd->tty; - kobjp = &hvcsd->kobj; - spin_unlock_irqrestore(&hvcsd->lock, flags); /* * Let the last holder of this object cause it to be removed, which * would probably be tty_hangup below. */ - kobject_put (kobjp); + kref_put(&hvcsd->kref, destroy_hvcs_struct); /* * The hangup is a scheduled function which will auto chain call @@ -1086,7 +1072,7 @@ static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address, } /* - * This always increments the kobject ref count if the call is successful. + * This always increments the kref ref count if the call is successful. * Please remember to dec when you are done with the instance. * * NOTICE: Do NOT hold either the hvcs_struct.lock or hvcs_structs_lock when @@ -1103,7 +1089,7 @@ static struct hvcs_struct *hvcs_get_by_index(int index) list_for_each_entry(hvcsd, &hvcs_structs, next) { spin_lock_irqsave(&hvcsd->lock, flags); if (hvcsd->index == index) { - kobject_get(&hvcsd->kobj); + kref_get(&hvcsd->kref); spin_unlock_irqrestore(&hvcsd->lock, flags); spin_unlock(&hvcs_structs_lock); return hvcsd; @@ -1129,14 +1115,13 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp) unsigned int irq; struct vio_dev *vdev; unsigned long unit_address; - struct kobject *kobjp; if (tty->driver_data) goto fast_open; /* * Is there a vty-server that shares the same index? - * This function increments the kobject index. + * This function increments the kref index. */ if (!(hvcsd = hvcs_get_by_index(tty->index))) { printk(KERN_WARNING "HVCS: open failed, no device associated" @@ -1181,7 +1166,7 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp) * and will grab the spinlock and free the connection if it fails. */ if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) { - kobject_put(&hvcsd->kobj); + kref_put(&hvcsd->kref, destroy_hvcs_struct); printk(KERN_WARNING "HVCS: enable device failed.\n"); return rc; } @@ -1192,17 +1177,11 @@ fast_open: hvcsd = tty->driver_data; spin_lock_irqsave(&hvcsd->lock, flags); - if (!kobject_get(&hvcsd->kobj)) { - spin_unlock_irqrestore(&hvcsd->lock, flags); - printk(KERN_ERR "HVCS: Kobject of open" - " hvcs doesn't exist.\n"); - return -EFAULT; /* Is this the right return value? */ - } - + kref_get(&hvcsd->kref); hvcsd->open_count++; - hvcsd->todo_mask |= HVCS_SCHED_READ; spin_unlock_irqrestore(&hvcsd->lock, flags); + open_success: hvcs_kick(); @@ -1212,9 +1191,8 @@ open_success: return 0; error_release: - kobjp = &hvcsd->kobj; spin_unlock_irqrestore(&hvcsd->lock, flags); - kobject_put(&hvcsd->kobj); + kref_put(&hvcsd->kref, destroy_hvcs_struct); printk(KERN_WARNING "HVCS: partner connect failed.\n"); return retval; @@ -1224,7 +1202,6 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) { struct hvcs_struct *hvcsd; unsigned long flags; - struct kobject *kobjp; int irq = NO_IRQ; /* @@ -1245,7 +1222,6 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) hvcsd = tty->driver_data; spin_lock_irqsave(&hvcsd->lock, flags); - kobjp = &hvcsd->kobj; if (--hvcsd->open_count == 0) { vio_disable_interrupts(hvcsd->vdev); @@ -1270,7 +1246,7 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) tty->driver_data = NULL; free_irq(irq, hvcsd); - kobject_put(kobjp); + kref_put(&hvcsd->kref, destroy_hvcs_struct); return; } else if (hvcsd->open_count < 0) { printk(KERN_ERR "HVCS: vty-server@%X open_count: %d" @@ -1279,7 +1255,7 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp) } spin_unlock_irqrestore(&hvcsd->lock, flags); - kobject_put(kobjp); + kref_put(&hvcsd->kref, destroy_hvcs_struct); } static void hvcs_hangup(struct tty_struct * tty) @@ -1287,21 +1263,17 @@ static void hvcs_hangup(struct tty_struct * tty) struct hvcs_struct *hvcsd = tty->driver_data; unsigned long flags; int temp_open_count; - struct kobject *kobjp; int irq = NO_IRQ; spin_lock_irqsave(&hvcsd->lock, flags); - /* Preserve this so that we know how many kobject refs to put */ + /* Preserve this so that we know how many kref refs to put */ temp_open_count = hvcsd->open_count; /* - * Don't kobject put inside the spinlock because the destruction + * Don't kref put inside the spinlock because the destruction * callback may use the spinlock and it may get called before the - * spinlock has been released. Get a pointer to the kobject and - * kobject_put on that after releasing the spinlock. + * spinlock has been released. */ - kobjp = &hvcsd->kobj; - vio_disable_interrupts(hvcsd->vdev); hvcsd->todo_mask = 0; @@ -1324,7 +1296,7 @@ static void hvcs_hangup(struct tty_struct * tty) free_irq(irq, hvcsd); /* - * We need to kobject_put() for every open_count we have since the + * We need to kref_put() for every open_count we have since the * tty_hangup() function doesn't invoke a close per open connection on a * non-console device. */ @@ -1335,7 +1307,7 @@ static void hvcs_hangup(struct tty_struct * tty) * NOTE: If this hangup was signaled from user space then the * final put will never happen. */ - kobject_put(kobjp); + kref_put(&hvcsd->kref, destroy_hvcs_struct); } } -- 2.7.4