PCI: let the core manage slot names
Subsystems (5)
v4 cover PCI: let the core manage slot names
Hi all,
This is v4 of the series that implements a series of changes that allows the PCI core to manage slot names, rather than individual hotplug drivers.
Thank you to Kenji-san and Taku-san for testing and finding my bugs. Thanks to Willy for helping me out with the locking issues in pci_hp_register.
Again, I have tested by loading pci_slot, acpiphp, and fakephp in various combinations, and using the new dup_slots=1 param to fakephp. I also had:
CONFIG_DEBUG_SPINLOCK=yCONFIG_DEBUG_MUTEXES=yCONFIG_DEBUG_SPINLOCK_SLEEP=y
and didn't see any complaints.
This series applies against Jesse's linux-next branch. I just fetched his branch and peeked at it, and based on the log, my series _should_ apply with minimal fuzz (but I didn't do a rebase because I didn't think to check until writing this mail ;).
It would be great if folks could give one last (hopefully!) review.
Thanks.
/ac
v3 -> v4:
- Do not access hotplug_slot_name() before name initialization
- Serialize pci_hp_register/deregister
v2 -> v3:
- incorporate Willy's code review comments
- fix possible memory leak, pointed out by Rolf Eike Beer
- make false name collision detection work for empty slots
- add 'dup_slots' module_param to fakephp to help debug all this ;)
v1 -> v2:
- fix possible false name collisions
---
Alex Chiang (15):
PCI Hotplug: fakephp: add duplicate slot name debugging
PCI: Hotplug core: remove 'name'
PCI: shcphp: remove 'name' parameter
PCI: SGI Hotplug: stop managing bss_hotplug_slot->name
PCI: rpaphp: kmalloc/kfree slot->name directly
PCI: pciehp: remove 'name' parameter
PCI: ibmphp: stop managing hotplug_slot->name
PCI: fakephp: remove 'name' parameter
PCI: cpqphp: stop managing hotplug_slot->name
PCI: cpci_hotplug: stop managing hotplug_slot->name
PCI: acpiphp: remove 'name' parameter
PCI, PCI Hotplug: introduce slot_name helpers
PCI: prevent duplicate slot names
PCI Hotplug: serialize pci_hp_register/deregister PCI Hotplug core: add 'name' param pci_hp_register interface
drivers/pci/hotplug/acpiphp.h | 9 +- drivers/pci/hotplug/acpiphp_core.c | 32 +++-- drivers/pci/hotplug/cpci_hotplug.h | 6 + drivers/pci/hotplug/cpci_hotplug_core.c | 75 +++++-------- drivers/pci/hotplug/cpci_hotplug_pci.c | 4 - drivers/pci/hotplug/cpqphp.h | 13 +- drivers/pci/hotplug/cpqphp_core.c | 43 +++---- drivers/pci/hotplug/fakephp.c | 26 +++- drivers/pci/hotplug/ibmphp.h | 5 - drivers/pci/hotplug/ibmphp_ebda.c | 19 +-- drivers/pci/hotplug/pci_hotplug_core.c | 68 ++++++------ drivers/pci/hotplug/pciehp.h | 9 +- drivers/pci/hotplug/pciehp_core.c | 49 +++----- drivers/pci/hotplug/pciehp_ctrl.c | 53 +++++---- drivers/pci/hotplug/pciehp_hpc.c | 1 drivers/pci/hotplug/rpaphp_slot.c | 9 +- drivers/pci/hotplug/sgi_hotplug.c | 18 +-- drivers/pci/hotplug/shpchp.h | 9 +- drivers/pci/hotplug/shpchp_core.c | 52 +++------ drivers/pci/hotplug/shpchp_ctrl.c | 48 ++++---- drivers/pci/slot.c | 181 +++++++++++++++++++++++-------- include/linux/pci.h | 9 +- include/linux/pci_hotplug.h | 11 +- 23 files changed, 407 insertions(+), 342 deletions(-)
PATCH v4 1/15 PCI Hotplug core: add 'name' param pci_hp_register interface
Update pci_hp_register() to take a const char *name parameter.
The motivation for this is to clean up the individual hotplug drivers so that each one does not have to manage its own name. The PCI core should be the place where we manage the name.
We update the interface and all callsites first, in a "no functional change" manner, and clean up the drivers later.
---
drivers/pci/hotplug/acpiphp_core.c | 3 ++- drivers/pci/hotplug/cpci_hotplug_core.c | 3 ++- drivers/pci/hotplug/cpqphp_core.c | 3 ++- drivers/pci/hotplug/fakephp.c | 3 ++- drivers/pci/hotplug/ibmphp_ebda.c | 3 ++- drivers/pci/hotplug/pci_hotplug_core.c | 15 ++++++++------- drivers/pci/hotplug/pciehp_core.c | 3 ++- drivers/pci/hotplug/rpaphp_slot.c | 2 +- drivers/pci/hotplug/sgi_hotplug.c | 3 ++- drivers/pci/hotplug/shpchp_core.c | 3 ++- include/linux/pci_hotplug.h | 3 ++- 11 files changed, 27 insertions(+), 17 deletions(-)
drivers/pci/hotplug/acpiphp_core.c +2 -1
@@ -340,7 +340,8 @@ int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot) retval =pci_hp_register (slot->hotplug_slot, acpiphp_slot->bridge->pci_bus, - acpiphp_slot->device); + acpiphp_slot->device, + slot->name);if (retval == -EBUSY ) goto error_hpslot;if (retval) {
drivers/pci/hotplug/cpci_hotplug_core.c +2 -1
@@ -285,7 +285,8 @@ cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last) info->attention_status =cpci_get_attention_status (slot);dbg ("registering slot %s" , slot->hotplug_slot->name); - status =pci_hp_register (slot->hotplug_slot, bus, i); + status =pci_hp_register (slot->hotplug_slot, bus, i, + slot->hotplug_slot->name);if (status) {err ("pci_hp_register failed with error %d" , status); goto error_name;
drivers/pci/hotplug/cpqphp_core.c +2 -1
@@ -436,7 +436,8 @@ static int ctrl_slot_setup(struct controller *ctrl, slot_number); result =pci_hp_register (hotplug_slot, ctrl->pci_dev->subordinate, - slot->device); + slot->device, + hotplug_slot->name);if (result) {err ("pci_hp_register failed with error %d\n" , result); goto error_name;
drivers/pci/hotplug/fakephp.c +2 -1
@@ -126,7 +126,8 @@ static int add_slot(struct pci_dev *dev) slot->release = &dummy_release; slot->private = dslot; - retval =pci_hp_register (slot, dev->bus,PCI_SLOT (dev->devfn)); + retval =pci_hp_register (slot, dev->bus,PCI_SLOT (dev->devfn), + slot->name);if (retval) {err ("pci_hp_register failed with error %d\n" , retval); goto error_dslot;
drivers/pci/hotplug/ibmphp_ebda.c +2 -1
@@ -966,7 +966,8 @@ static int __init ebda_rsrc_controller (void)list_for_each_entry (tmp_slot, &ibmphp_slot_head, ibm_slot_list) {snprintf (tmp_slot->hotplug_slot->name,30 ,"%s" ,create_file_name (tmp_slot));pci_hp_register (tmp_slot->hotplug_slot, -pci_find_bus (0 , tmp_slot->bus), tmp_slot->device); +pci_find_bus (0 , tmp_slot->bus), tmp_slot->device, + tmp_slot->hotplug_slot->name); }print_ebda_hpc ();
drivers/pci/hotplug/pci_hotplug_core.c +8 -7
@@ -547,13 +547,15 @@ out:* @bus: bus this slot is on * @slot: pointer to the &struct hotplug_slot to register * @slot_nr: slot number +* @name: name registered with kobject core * * Registers a hotplug slot with the pci hotplug subsystem, which will allow * userspace interaction to the slot. * * Returns 0 if successful, anything else for an error. */ -int pci_hp_register (struct hotplug_slot *slot,struct pci_bus *bus,int slot_nr) +int pci_hp_register (struct hotplug_slot *slot,struct pci_bus *bus,int slot_nr, +const char *name) {int result;struct pci_slot *pci_slot;
@@ -569,7 +571,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr) }/* Check if we have already registered a slot with the same name. */ -if (get_slot_from_name (slot->name)) +if (get_slot_from_name (name))return -EEXIST ;/*
@@ -577,7 +579,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr)* driver and call it here again. If we've already created the * pci_slot, the interface will simply bump the refcount. */ - pci_slot =pci_create_slot (bus, slot_nr, slot->name); + pci_slot =pci_create_slot (bus, slot_nr, name);if (IS_ERR (pci_slot))return PTR_ERR (pci_slot);
@@ -593,8 +595,8 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr)/* * Allow pcihp drivers to override the ACPI_PCI_SLOT name. */ -if (strcmp (kobject_name (&pci_slot->kobj), slot->name)) { - result =kobject_rename (&pci_slot->kobj, slot->name); +if (strcmp (kobject_name (&pci_slot->kobj), name)) { + result =kobject_rename (&pci_slot->kobj, name);if (result) {pci_destroy_slot (pci_slot);return result;
@@ -607,8 +609,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr) result =fs_add_slot (pci_slot);kobject_uevent (&pci_slot->kobj,KOBJ_ADD ); -dbg ("Added slot %s to the list\n" , slot->name); - +dbg ("Added slot %s to the list\n" , name);return result; }
drivers/pci/hotplug/pciehp_core.c +2 -1
@@ -226,7 +226,8 @@ static int init_slots(struct controller *ctrl) duplicate_name: retval =pci_hp_register (hotplug_slot, ctrl->pci_dev->subordinate, - slot->device); + slot->device, + slot->name);if (retval) {/* * If slot N already exists, we'll try to create
drivers/pci/hotplug/rpaphp_slot.c +1 -1
@@ -137,7 +137,7 @@ int rpaphp_register_slot(struct slot *slot) slotno =PCI_SLOT (PCI_DN (slot->dn->child)->devfn); else slotno =-1 ; - retval =pci_hp_register (php_slot, slot->bus, slotno); + retval =pci_hp_register (php_slot, slot->bus, slotno, slot->name);if (retval) {err ("pci_hp_register failed with error %d\n" , retval);return retval;
drivers/pci/hotplug/sgi_hotplug.c +2 -1
@@ -653,7 +653,8 @@ static int sn_hotplug_slot_register(struct pci_bus *pci_bus) bss_hotplug_slot->ops = &sn_hotplug_slot_ops; bss_hotplug_slot->release = &sn_release_slot; - rc =pci_hp_register (bss_hotplug_slot, pci_bus, device); + rc =pci_hp_register (bss_hotplug_slot, pci_bus, device, + bss_hotplug_slot->name);if (rc) goto register_err;
drivers/pci/hotplug/shpchp_core.c +2 -1
@@ -146,7 +146,8 @@ static int init_slots(struct controller *ctrl) slot->hp_slot, slot->number, ctrl->slot_device_offset); duplicate_name: retval =pci_hp_register (slot->hotplug_slot, - ctrl->pci_dev->subordinate, slot->device); + ctrl->pci_dev->subordinate, slot->device, + hotplug_slot->name);if (retval) {/* * If slot N already exists, we'll try to create
include/linux/pci_hotplug.h +2 -1
@@ -165,7 +165,8 @@ struct hotplug_slot { };#define to_hotplug_slot (n) container_of(n, struct hotplug_slot, kobj) -extern int pci_hp_register (struct hotplug_slot *,struct pci_bus *,int nr); +extern int pci_hp_register (struct hotplug_slot *,struct pci_bus *,int nr, +const char *name);extern int pci_hp_deregister (struct hotplug_slot *slot);extern int __must_check pci_hp_change_slot_info (struct hotplug_slot *slot,struct hotplug_slot_info *info);
Re: [PATCH v4 01/15] PCI Hotplug core: add 'name' param pci_hp_register interface
Quoted 9 lines · Alex Chiang
Update
pci_hp_register()to take a const char *name parameter.The motivation for this is to clean up the individual hotplug drivers so that each one does not have to manage its own name. The PCI core should be the place where we manage the name.
We update the interface and all callsites first, in a "no functional change" manner, and clean up the drivers later.
Quoted 7 lines
Signed-off-by Alex Chiang <[email protected]>---
Simple, clean, obvious.
Signature · 4 lines
Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."
PATCH v4 2/15 PCI Hotplug: serialize pci_hp_register/deregister
In reply to Alex ChiangAdd explicit locking to pci_hp_register/deregister. For a given pci_slot, we want to make sure that the pci_slot->hotplug pointer isn't being changed from underneath us.
---
drivers/pci/hotplug/pci_hotplug_core.c | 7 +++++++ drivers/pci/slot.c | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-)
drivers/pci/hotplug/pci_hotplug_core.c +7 -0
@@ -37,6 +37,7 @@#include <linux/init.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/mutex.h> #include <linux/pci.h> #include <linux/pci_hotplug.h> #include <asm/uaccess.h>
@@ -554,6 +555,7 @@ out:* * Returns 0 if successful, anything else for an error. */ +static DEFINE_MUTEX (pci_hp_mutex);int pci_hp_register (struct hotplug_slot *slot,struct pci_bus *bus,int slot_nr,const char *name) {
@@ -583,7 +585,9 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,if (IS_ERR (pci_slot))return PTR_ERR (pci_slot); +mutex_lock (&pci_hp_mutex);if (pci_slot->hotplug) { +mutex_unlock (&pci_hp_mutex);dbg ("%s: already claimed\n" , __func__);pci_destroy_slot (pci_slot);return -EBUSY ;
@@ -591,6 +595,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, slot->pci_slot = pci_slot; pci_slot->hotplug = slot; +mutex_unlock (&pci_hp_mutex);/* * Allow pcihp drivers to override the ACPI_PCI_SLOT name.
@@ -635,6 +640,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)if (temp != hotplug)return -ENODEV ; +mutex_lock (&pci_hp_mutex);spin_lock (&pci_hotplug_slot_list_lock);list_del (&hotplug->slot_list);spin_unlock (&pci_hotplug_slot_list_lock);
@@ -645,6 +651,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) hotplug->release (hotplug); slot->hotplug =NULL ; +mutex_unlock (&pci_hp_mutex);pci_destroy_slot (slot);return 0 ;
drivers/pci/slot.c +2 -2
@@ -164,10 +164,10 @@ placeholder:pr_debug ("%s: created pci_slot on %04x:%02x:%02x\n" , __func__,pci_domain_nr (parent), parent->number, slot_nr); - out: +out:up_write (&pci_bus_sem);return slot; - err: +err:kfree (slot); slot =ERR_PTR (err); goto out;
Re: [PATCH v4 02/15] PCI Hotplug: serialize pci_hp_register/deregister
Quoted 3 lines · Alex Chiang
Add explicit locking to pci_hp_register/deregister. For a given
pci_slot, we want to make sure that thepci_slot->hotplugpointer isn't being changed from underneath us.
I'm torn between saying this goes too far and this doesn't go far enough. If pci_hp_register() and pci_hp_deregister() can race against each other, then I don't like the way we grab, release, grab, release the pci_hotplug_slot_list_lock in pci_hp_deregister()/get_slot_from_name(). I think it would be smarter to grab the pci_hotplug_slot_list_lock before calling get_slot_from_name() and release it after the list_del().
Mind you, I can't see a race there, but I'm also not at my best today and it's possible there's one there I can't see.
As it currently stands, I don't think it needs to be a mutex -- do we do anything sleeping under it?
Another part of me says "Just slap a mutex around both functions and have done with it".
So, in summary, more eyes on this please. I don't think I can do a good job today at spotting races.
Quoted 61 lines
drivers/pci/hotplug/pci_hotplug_core.c +7
-0@@ -37,6 +37,7 @@#include <linux/init.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/mutex.h> #include <linux/pci.h> #include <linux/pci_hotplug.h> #include <asm/uaccess.h> @@ -554,6 +555,7 @@ out:* * Returns 0 if successful, anything else for an error. */ +static DEFINE_MUTEX (pci_hp_mutex);int pci_hp_register (struct hotplug_slot *slot,struct pci_bus *bus,int slot_nr,const char *name) {@@ -583,7 +585,9 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,if (IS_ERR (pci_slot))return PTR_ERR (pci_slot); +mutex_lock (&pci_hp_mutex);if (pci_slot->hotplug) { +mutex_unlock (&pci_hp_mutex);dbg ("%s: already claimed\n" , __func__);pci_destroy_slot (pci_slot);return -EBUSY ;@@ -591,6 +595,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, slot->pci_slot = pci_slot; pci_slot->hotplug = slot; +mutex_unlock (&pci_hp_mutex);/* * Allow pcihp drivers to override the ACPI_PCI_SLOT name. @@ -635,6 +640,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)if (temp != hotplug)return -ENODEV ; +mutex_lock (&pci_hp_mutex);spin_lock (&pci_hotplug_slot_list_lock);list_del (&hotplug->slot_list);spin_unlock (&pci_hotplug_slot_list_lock);@@ -645,6 +651,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) hotplug->release (hotplug); slot->hotplug =NULL ; +mutex_unlock (&pci_hp_mutex);pci_destroy_slot (slot);return 0 ;drivers/pci/slot.c +0
-0@@ -164,10 +164,10 @@ placeholder:pr_debug ("%s: created pci_slot on %04x:%02x:%02x\n" , __func__,pci_domain_nr (parent), parent->number, slot_nr);
drivers/pci/slot.c placeholder: · line 173
Quoted 10 lines
drivers/pci/slot.c +2
-2- out: +out:up_write (&pci_bus_sem);return slot; - err: +err:kfree (slot); slot =ERR_PTR (err); goto out;
Gratuitous whitespace change?
Signature · 4 lines
Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."
Re: [PATCH v4 02/15] PCI Hotplug: serialize pci_hp_register/deregister
* Matthew Wilcox <[email protected]>:
Quoted 8 lines · Alex Chiang
Quoted 3 lines
Add explicit locking to pci_hp_register/deregister. For a given
pci_slot, we want to make sure that thepci_slot->hotplugpointer isn't being changed from underneath us.I'm torn between saying this goes too far and this doesn't go far enough. If
pci_hp_register()andpci_hp_deregister()can race against each other,
I think Kenji-san was more worried about the race for multiple callers of pci_create_slot() and all the horrible crap I was introducing to account for slot renaming.
I've figured out a different approach which I'll be sending out shortly. I didn't change any of the locking semantics in pci_hp_register/deregister, so I disclaim responsibility for any existing races that exist today. ;) (note, I don't think there are any).
Quoted 8 lines
Quoted 8 lines
drivers/pci/slot.c +0
-0@@ -164,10 +164,10 @@ placeholder:pr_debug ("%s: created pci_slot on %04x:%02x:%02x\n" , __func__,pci_domain_nr (parent), parent->number, slot_nr);
Quoted 11 lines
drivers/pci/slot.c placeholder: · line 173
Quoted 9 lines
drivers/pci/slot.c +2
-2- out: +out:up_write (&pci_bus_sem);return slot; - err: +err:kfree (slot); slot =ERR_PTR (err); goto out;Gratuitous whitespace change?
Maybe... I'm gonna keep this same hunk, but fold it into a bigger patch so it won't be as noticable. ;)
/ac
Re: [PATCH v4 02/15] PCI Hotplug: serialize pci_hp_register/deregister
In reply to Alex ChiangI think we no longer need pci_hotplug_slot_list_lock with your patch.
Thanks,
Kenji Kaneshige
Quoted 93 lines · Alex Chiang
Add explicit locking to pci_hp_register/deregister. For a given
pci_slot, we want to make sure that thepci_slot->hotplugpointer isn't being changed from underneath us.Signed-off-by Alex Chiang <[email protected]>---
drivers/pci/hotplug/pci_hotplug_core.c | 7 +++++++ drivers/pci/slot.c | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-)drivers/pci/hotplug/pci_hotplug_core.c +7
-0@@ -37,6 +37,7 @@#include <linux/init.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/mutex.h> #include <linux/pci.h> #include <linux/pci_hotplug.h> #include <asm/uaccess.h> @@ -554,6 +555,7 @@ out:* * Returns 0 if successful, anything else for an error. */ +static DEFINE_MUTEX (pci_hp_mutex);int pci_hp_register (struct hotplug_slot *slot,struct pci_bus *bus,int slot_nr,const char *name) {@@ -583,7 +585,9 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,if (IS_ERR (pci_slot))return PTR_ERR (pci_slot); +mutex_lock (&pci_hp_mutex);if (pci_slot->hotplug) { +mutex_unlock (&pci_hp_mutex);dbg ("%s: already claimed\n" , __func__);pci_destroy_slot (pci_slot);return -EBUSY ;@@ -591,6 +595,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, slot->pci_slot = pci_slot; pci_slot->hotplug = slot; +mutex_unlock (&pci_hp_mutex);/* * Allow pcihp drivers to override the ACPI_PCI_SLOT name. @@ -635,6 +640,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)if (temp != hotplug)return -ENODEV ; +mutex_lock (&pci_hp_mutex);spin_lock (&pci_hotplug_slot_list_lock);list_del (&hotplug->slot_list);spin_unlock (&pci_hotplug_slot_list_lock);@@ -645,6 +651,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) hotplug->release (hotplug); slot->hotplug =NULL ; +mutex_unlock (&pci_hp_mutex);pci_destroy_slot (slot);return 0 ;drivers/pci/slot.c +2
-3@@ -164,10 +164,10 @@ placeholder:pr_debug ("%s: created pci_slot on %04x:%02x:%02x\n" , __func__,pci_domain_nr (parent), parent->number, slot_nr); - out: +out:up_write (&pci_bus_sem);return slot; - err: +err:kfree (slot); slot =ERR_PTR (err); goto out; --To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to [email protected]
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PATCH v4 3/15 PCI: prevent duplicate slot names
In reply to Alex ChiangPrevent callers of pci_create_slot() from registering slots with duplicate names. This condition occurs most often when PCI hotplug drivers are loaded on platforms with broken firmware that assigns identical names to multiple slots.
We now rename these duplicate slots on behalf of the user.
If firmware assigns the name N to multiple slots, then:
The first registered slot is assigned N The second registered slot is assigned N-1 The third registered slot is assigned N-2 etc.
A side effect of this patch is that the error condition for when multiple drivers attempt to claim the same slot becomes much more prominent.
In other words, the previous error condition returned for duplicate slot names (-EEXIST) masked the case when multiple drivers attempted to claim the same slot. Now, the -EBUSY return makes the true error more obvious.
This is the permanent fix mentioned in earlier commits:
shpchp: Rename duplicate slot name N as N-1, N-2, N-M... d6a9e9b40be7da84f82eb414c2ad98c5bb69986b pciehp: Rename duplicate slot name N as N-1, N-2, N-M... 167e782e301188c7c7e31e486bbeea5f918324c1
This commit also introduces two new PCI core interfaces:
struct pci_slot *pci_get_pci_slot(struct pci_bus *parent, int slot_nr); void pci_renumber_slot(struct pci_slot *slot, int slot_nr);
And removes the old, unused pci_update_slot_number() API.
---
drivers/pci/hotplug/pci_hotplug_core.c | 52 ++++----- drivers/pci/hotplug/pciehp_core.c | 15 --- drivers/pci/hotplug/shpchp_core.c | 15 --- drivers/pci/slot.c | 177 ++++++++++++++++++++++++-------- include/linux/pci.h | 4 + 5 files changed, 160 insertions(+), 103 deletions(-)
drivers/pci/hotplug/pci_hotplug_core.c +24 -28
@@ -572,41 +572,32 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,return -EINVAL ; } -/* Check if we have already registered a slot with the same name. */ -if (get_slot_from_name (name)) -return -EEXIST ; -/* -* No problems if we call this interface from both ACPI_PCI_SLOT -* driver and call it here again. If we've already created the -* pci_slot, the interface will simply bump the refcount. +* Look for existing slot. If we find it, and it was created by a +* slot detection driver (ie, doesn't have a ->hotplug()) then we +* allow the hotplug driver calling us to rename the slot if desired. +* +* Otherwise, create the slot and carry on with life. */ - pci_slot =pci_create_slot (bus, slot_nr, name); -if (IS_ERR (pci_slot)) -return PTR_ERR (pci_slot); -mutex_lock (&pci_hp_mutex); -if (pci_slot->hotplug) { -mutex_unlock (&pci_hp_mutex); -dbg ("%s: already claimed\n" , __func__); -pci_destroy_slot (pci_slot); -return -EBUSY ; + pci_slot =pci_get_pci_slot (bus, slot_nr); +if (pci_slot) { +if (pci_slot->hotplug) { + result = -EBUSY ; + goto err; + } + +if (strcmp (kobject_name (&pci_slot->kobj), name)) +if ((result =pci_rename_slot (pci_slot, name))) + goto err; + }else { + pci_slot =pci_create_slot (bus, slot_nr, name); +if ((result =IS_ERR (pci_slot))) + goto out; } slot->pci_slot = pci_slot; pci_slot->hotplug = slot; -mutex_unlock (&pci_hp_mutex); - -/* -* Allow pcihp drivers to override the ACPI_PCI_SLOT name. -*/ -if (strcmp (kobject_name (&pci_slot->kobj), name)) { - result =kobject_rename (&pci_slot->kobj, name); -if (result) { -pci_destroy_slot (pci_slot); -return result; - } - }spin_lock (&pci_hotplug_slot_list_lock);list_add (&slot->slot_list, &pci_hotplug_slot_list);
@@ -616,7 +607,12 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,kobject_uevent (&pci_slot->kobj,KOBJ_ADD );dbg ("Added slot %s to the list\n" , name); +out: +mutex_unlock (&pci_hp_mutex);return result; +err: +pci_destroy_slot (pci_slot); + goto out; }/**
drivers/pci/hotplug/pciehp_core.c +0 -15
@@ -196,7 +196,6 @@ static int init_slots(struct controller *ctrl)struct slot *slot;struct hotplug_slot *hotplug_slot;struct hotplug_slot_info *info; -int len, dup =1 ;int retval = -ENOMEM ;list_for_each_entry (slot, &ctrl->slot_list, slot_list) {
@@ -223,25 +222,11 @@ static int init_slots(struct controller *ctrl)ctrl_dbg (ctrl,"Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n" , slot->bus, slot->device, slot->hp_slot, slot->number, ctrl->slot_device_offset); -duplicate_name: retval =pci_hp_register (hotplug_slot, ctrl->pci_dev->subordinate, slot->device, slot->name);if (retval) { -/* -* If slot N already exists, we'll try to create -* slot N-1, N-2 ... N-M, until we overflow. -*/ -if (retval == -EEXIST ) { - len =snprintf (slot->name,SLOT_NAME_SIZE , -"%d-%d" , slot->number, dup++); -if (len <SLOT_NAME_SIZE ) - goto duplicate_name; -else -ctrl_err (ctrl,"duplicate slot name " -"overflow\n" ); - }ctrl_err (ctrl,"pci_hp_register failed with error %d\n" , retval); goto error_info;
drivers/pci/hotplug/shpchp_core.c +1 -14
@@ -102,7 +102,7 @@ static int init_slots(struct controller *ctrl)struct hotplug_slot *hotplug_slot;struct hotplug_slot_info *info;int retval = -ENOMEM ; -int i, len, dup =1 ; +int i;for (i =0 ; i < ctrl->num_slots; i++) { slot =kzalloc (sizeof (*slot),GFP_KERNEL );
@@ -144,23 +144,10 @@ static int init_slots(struct controller *ctrl)dbg ("Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n" , slot->bus, slot->device, slot->hp_slot, slot->number, ctrl->slot_device_offset); -duplicate_name: retval =pci_hp_register (slot->hotplug_slot, ctrl->pci_dev->subordinate, slot->device, hotplug_slot->name);if (retval) { -/* -* If slot N already exists, we'll try to create -* slot N-1, N-2 ... N-M, until we overflow. -*/ -if (retval == -EEXIST ) { - len =snprintf (slot->name,SLOT_NAME_SIZE , -"%d-%d" , slot->number, dup++); -if (len <SLOT_NAME_SIZE ) - goto duplicate_name; -else -err ("duplicate slot name overflow\n" ); - }err ("pci_hp_register failed with error %d\n" , retval); goto error_info; }
drivers/pci/slot.c +132 -45
258 lines not on this page · raw message
include/linux/pci.h +3 -1
@@ -509,8 +509,10 @@ struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr);struct pci_slot *pci_create_slot (struct pci_bus *parent,int slot_nr,const char *name); +struct pci_slot *pci_get_pci_slot (struct pci_bus *parent,int slot_nr);void pci_destroy_slot (struct pci_slot *slot); -void pci_update_slot_number (struct pci_slot *slot,int slot_nr); +int pci_rename_slot (struct pci_slot *slot,const char *name); +void pci_renumber_slot (struct pci_slot *slot,int slot_nr);int pci_scan_slot (struct pci_bus *bus,int devfn);struct pci_dev *pci_scan_single_device (struct pci_bus *bus,int devfn);void pci_device_add (struct pci_dev *dev,struct pci_bus *bus);
Re: [PATCH v4 03/15] PCI: prevent duplicate slot names
Alex Chiang wrote:
(snip.)
Quoted 38 lines
drivers/pci/hotplug/pci_hotplug_core.c +11
-16@@ -572,41 +572,32 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,return -EINVAL ; } -/* Check if we have already registered a slot with the same name. */ -if (get_slot_from_name (name)) -return -EEXIST ; -/* -* No problems if we call this interface from both ACPI_PCI_SLOT -* driver and call it here again. If we've already created the -* pci_slot, the interface will simply bump the refcount. +* Look for existing slot. If we find it, and it was created by a +* slot detection driver (ie, doesn't have a ->hotplug()) then we +* allow the hotplug driver calling us to rename the slot if desired. +* +* Otherwise, create the slot and carry on with life. */ - pci_slot =pci_create_slot (bus, slot_nr, name); -if (IS_ERR (pci_slot)) -return PTR_ERR (pci_slot); -mutex_lock (&pci_hp_mutex); -if (pci_slot->hotplug) { -mutex_unlock (&pci_hp_mutex); -dbg ("%s: already claimed\n" , __func__); -pci_destroy_slot (pci_slot); -return -EBUSY ; + pci_slot =pci_get_pci_slot (bus, slot_nr); +if (pci_slot) { +if (pci_slot->hotplug) { + result = -EBUSY ; + goto err; + }
drivers/pci/hotplug/pci_hotplug_core.c int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, · line 598
Quoted 10 lines
drivers/pci/hotplug/pci_hotplug_core.c +8
-0+ +if (strcmp (kobject_name (&pci_slot->kobj), name)) +if ((result =pci_rename_slot (pci_slot, name))) + goto err; + }else { + pci_slot =pci_create_slot (bus, slot_nr, name); +if ((result =IS_ERR (pci_slot))) + goto out; }
I think there still remain race condition. The situation I imagine is as follows, though I might be misunderstanding something.
If pci_slot driver created pci_slot between pci_get_pci_slot() and pci_create_slot() in pci_hp_register() in the hotplug driver's thread, pci_rename_slot() would never be called and name specified by pci_slot driver would be used instead of the one specified by hotplug driver.
Quoted 15 lines
drivers/pci/hotplug/pci_hotplug_core.c +2
-4-void pci_update_slot_number (struct pci_slot *slot,int slot_nr) +void pci_renumber_slot (struct pci_slot *slot,int slot_nr) { -int name_count =0 ;struct pci_slot *tmp;down_write (&pci_bus_sem);list_for_each_entry (tmp, &slot->bus->slots, list) {WARN_ON (tmp->number == slot_nr); -if (!strcmp (kobject_name (&tmp->kobj),kobject_name (&slot->kobj))) - name_count++; + goto out; }
drivers/pci/hotplug/pci_hotplug_core.c int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,
Quoted 10 lines
drivers/pci/hotplug/pci_hotplug_core.c +2
-4-if (name_count >1 ) -printk (KERN_WARNING "pci_update_slot_number found %d slots with the same name: %s\n" , name_count,kobject_name (&slot->kobj)); - slot->number = slot_nr; +out:up_write (&pci_bus_sem); } -EXPORT_SYMBOL_GPL (pci_update_slot_number); +EXPORT_SYMBOL_GPL (pci_renumber_slot);
You changed exported symbol name. I think it should be made as an another patch.
Thanks,
Kenji Kaneshige
Re: [PATCH v4 03/15] PCI: prevent duplicate slot names
* Kenji Kaneshige <[email protected]>:
Quoted 53 lines
Quoted 37 lines · Alex Chiang
drivers/pci/hotplug/pci_hotplug_core.c +11
-15@@ -572,41 +572,32 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,return -EINVAL ; } -/* Check if we have already registered a slot with the same name. */ - if (get_slot_from_name(name)) - return -EEXIST; -/* -* No problems if we call this interface from both ACPI_PCI_SLOT -* driver and call it here again. If we've already created the -* pci_slot, the interface will simply bump the refcount. +* Look for existing slot. If we find it, and it was created by a +* slot detection driver (ie, doesn't have a ->hotplug()) then we +* allow the hotplug driver calling us to rename the slot if desired. +* +* Otherwise, create the slot and carry on with life. */ - pci_slot =pci_create_slot (bus, slot_nr, name); -if (IS_ERR (pci_slot)) -return PTR_ERR (pci_slot); -mutex_lock (&pci_hp_mutex); -if (pci_slot->hotplug) { -mutex_unlock (&pci_hp_mutex); -dbg ("%s: already claimed\n" , __func__); -pci_destroy_slot (pci_slot); -return -EBUSY ; + pci_slot =pci_get_pci_slot (bus, slot_nr); +if (pci_slot) { +if (pci_slot->hotplug) { + result = -EBUSY ; + goto err; + }drivers/pci/hotplug/pci_hotplug_core.c int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, · line 598
Quoted 10 lines
drivers/pci/hotplug/pci_hotplug_core.c +8
-0+ +if (strcmp (kobject_name (&pci_slot->kobj), name)) +if ((result =pci_rename_slot (pci_slot, name))) + goto err; + }else { + pci_slot =pci_create_slot (bus, slot_nr, name); +if ((result =IS_ERR (pci_slot))) + goto out; }I think there still remain race condition. The situation I imagine is as follows, though I might be misunderstanding something.
Quoted 4 lines
If
pci_slotdriver createdpci_slotbetweenpci_get_pci_slot()andpci_create_slot()inpci_hp_register()in the hotplug driver's thread,pci_rename_slot()would never be called and name specified bypci_slotdriver would be used instead of the one specified by hotplug driver.
Ah, now I finally understand.
And I think the solution is to avoid all the crap code I've been introducing into pci_hp_register.
A better way to do it would be to make slot creation and name override into one atomic operation, inside of pci_create_slot.
We are already serializing pci_create_slot by acquiring pci_bus_sem, so that should prevent any race condition.
I wrote a long changelog entry for my patches that should explain it all.
Please review. :)
Quoted 17 lines
Quoted 17 lines
drivers/pci/hotplug/pci_hotplug_core.c +3
-6-void pci_update_slot_number (struct pci_slot *slot,int slot_nr) +void pci_renumber_slot (struct pci_slot *slot,int slot_nr) { -int name_count =0 ;struct pci_slot *tmp;down_write (&pci_bus_sem);list_for_each_entry (tmp, &slot->bus->slots, list) {WARN_ON (tmp->number == slot_nr); -if (!strcmp (kobject_name (&tmp->kobj),kobject_name (&slot->kobj))) - name_count++; + goto out; } - if (name_count > 1) -printk (KERN_WARNING "pci_update_slot_number found %d slots with the same name: %s\n" , name_count,kobject_name (&slot->kobj)); - slot->number = slot_nr; +out:
Quoted 8 lines
drivers/pci/hotplug/pci_hotplug_core.c
Quoted 5 lines
drivers/pci/hotplug/pci_hotplug_core.c +1
-1up_write (&pci_bus_sem); } -EXPORT_SYMBOL_GPL (pci_update_slot_number); +EXPORT_SYMBOL_GPL (pci_renumber_slot);You changed exported symbol name. I think it should be made as an another patch.
Ok.
Thanks.
/ac
PATCH v4 4/15 PCI, PCI Hotplug: introduce slot_name helpers
In reply to Alex ChiangIn preparation for cleaning up the various hotplug drivers such that they don't have to manage their own 'name' parameters anymore, we provide the following convenience functions:
pci_slot_name() hotplug_slot_name()
These helpers will be used by individual hotplug drivers.
---
include/linux/pci.h | 5 +++++ include/linux/pci_hotplug.h | 5 +++++ 2 files changed, 10 insertions(+), 0 deletions(-)
include/linux/pci.h +5 -0
@@ -64,6 +64,11 @@ struct pci_slot {struct kobject kobj; }; +static inline const char *pci_slot_name (const struct pci_slot *slot) +{ +return kobject_name (&slot->kobj); +} +/* File state for mmap()s on /proc/bus/pci/X/Y */ enum pci_mmap_state { pci_mmap_io,
include/linux/pci_hotplug.h +5 -0
@@ -165,6 +165,11 @@ struct hotplug_slot { };#define to_hotplug_slot (n) container_of(n, struct hotplug_slot, kobj) +static inline const char *hotplug_slot_name (const struct hotplug_slot *slot) +{ +return pci_slot_name (slot->pci_slot); +} +extern int pci_hp_register (struct hotplug_slot *,struct pci_bus *,int nr,const char *name);extern int pci_hp_deregister (struct hotplug_slot *slot);
PATCH v4 5/15 PCI: acpiphp: remove 'name' parameter
In reply to Alex ChiangWe do not need to manage our own name parameter, especially since the PCI core can change it on our behalf, in the case of duplicate slot names.
Remove 'name' from acpiphp's version of struct slot.
---
drivers/pci/hotplug/acpiphp.h | 9 +++++---- drivers/pci/hotplug/acpiphp_core.c | 31 ++++++++++++++++--------------- 2 files changed, 21 insertions(+), 19 deletions(-)
drivers/pci/hotplug/acpiphp.h +5 -4
@@ -50,9 +50,6 @@ #define info(format, arg...) printk(KERN_INFO "%s: " format, MY_NAME , ## arg) #define warn(format, arg...) printk(KERN_WARNING "%s: " format, MY_NAME , ## arg) -/* name size which is used for entries in pcihpfs */ -#define SLOT_NAME_SIZE 20/* {_SUN} */ -struct acpiphp_bridge ;struct acpiphp_slot ;
@@ -63,9 +60,13 @@ struct slot {struct hotplug_slot *hotplug_slot;struct acpiphp_slot *acpi_slot;struct hotplug_slot_info info; -char name[SLOT_NAME_SIZE ]; }; +static inline const char *slot_name (struct slot *slot) +{ +return hotplug_slot_name (slot->hotplug_slot); +} +/* * struct acpiphp_bridge - PCI bridge information *
drivers/pci/hotplug/acpiphp_core.c +16 -15
@@ -44,6 +44,9 @@#define MY_NAME "acpiphp" +/* name size which is used for entries in pcihpfs */ +#define SLOT_NAME_SIZE 21/* {_SUN} */ +static int debug;int acpiphp_debug;
@@ -84,7 +87,6 @@ static struct hotplug_slot_ops acpi_hotplug_slot_ops = { .get_adapter_status = get_adapter_status, }; -/** * acpiphp_register_attention - set attention LED callback * @info: must be completely filled with LED callbacks
@@ -136,7 +138,7 @@ static int enable_slot(struct hotplug_slot *hotplug_slot) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));/* enable the specified slot */ return acpiphp_enable_slot (slot->acpi_slot);
@@ -154,7 +156,7 @@ static int disable_slot(struct hotplug_slot *hotplug_slot)struct slot *slot = hotplug_slot->private;int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));/* disable the specified slot */ retval =acpiphp_disable_slot (slot->acpi_slot);
@@ -177,7 +179,7 @@ static int disable_slot(struct hotplug_slot *hotplug_slot) {int retval = -ENODEV ; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,hotplug_slot_name (hotplug_slot));if (attention_info &&try_module_get (attention_info->owner)) { retval = attention_info->set_attn (hotplug_slot, status);
@@ -200,7 +202,7 @@ static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); *value =acpiphp_get_power_status (slot->acpi_slot);
@@ -222,7 +224,7 @@ static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value) {int retval = -EINVAL ; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,hotplug_slot_name (hotplug_slot));if (attention_info &&try_module_get (attention_info->owner)) { retval = attention_info->get_attn (hotplug_slot, value);
@@ -245,7 +247,7 @@ static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); *value =acpiphp_get_latch_status (slot->acpi_slot);
@@ -265,7 +267,7 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); *value =acpiphp_get_adapter_status (slot->acpi_slot);
@@ -299,7 +301,7 @@ static void release_slot(struct hotplug_slot *hotplug_slot) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));kfree (slot->hotplug_slot);kfree (slot);
@@ -310,6 +312,7 @@ int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot) {struct slot *slot;int retval = -ENOMEM ; +char name[SLOT_NAME_SIZE ]; slot =kzalloc (sizeof (*slot),GFP_KERNEL );if (!slot)
@@ -321,8 +324,6 @@ int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot) slot->hotplug_slot->info = &slot->info; - slot->hotplug_slot->name = slot->name; - slot->hotplug_slot->private = slot; slot->hotplug_slot->release = &release_slot; slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
@@ -336,12 +337,12 @@ int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot) slot->hotplug_slot->info->cur_bus_speed =PCI_SPEED_UNKNOWN ; acpiphp_slot->slot = slot; -snprintf (slot->name,sizeof (slot->name),"%u" , slot->acpi_slot->sun); +snprintf (name,SLOT_NAME_SIZE ,"%u" , slot->acpi_slot->sun); retval =pci_hp_register (slot->hotplug_slot, acpiphp_slot->bridge->pci_bus, acpiphp_slot->device, - slot->name); + name);if (retval == -EBUSY ) goto error_hpslot;if (retval) {
@@ -349,7 +350,7 @@ int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot) goto error_hpslot; } -info ("Slot [%s] registered\n" , slot->hotplug_slot->name); +info ("Slot [%s] registered\n" ,slot_name (slot));return 0 ; error_hpslot:
@@ -366,7 +367,7 @@ void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)struct slot *slot = acpiphp_slot->slot;int retval =0 ; -info ("Slot [%s] unregistered\n" , slot->hotplug_slot->name); +info ("Slot [%s] unregistered\n" ,slot_name (slot)); retval =pci_hp_deregister (slot->hotplug_slot);if (retval)
PATCH v4 6/15 PCI: cpci_hotplug: stop managing hotplug_slot->name
In reply to Alex ChiangWe no longer need to manage our version of hotplug_slot->name since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would like, and let the core take care of the rest.
---
drivers/pci/hotplug/cpci_hotplug.h | 6 ++ drivers/pci/hotplug/cpci_hotplug_core.c | 76 ++++++++++++------------------- drivers/pci/hotplug/cpci_hotplug_pci.c | 4 +- 3 files changed, 37 insertions(+), 49 deletions(-)
drivers/pci/hotplug/cpci_hotplug.h +6 -0
@@ -30,6 +30,7 @@#include <linux/types.h> #include <linux/pci.h> +#include <linux/pci_hotplug.h> /* PICMG 2.1 R2.0 HS CSR bits: */ #define HS_CSR_INS 0x0080
@@ -69,6 +70,11 @@ struct cpci_hp_controller {struct cpci_hp_controller_ops *ops; }; +static inline const char *slot_name (struct slot *slot) +{ +return hotplug_slot_name (slot->hotplug_slot); +} +extern int cpci_hp_register_controller (struct cpci_hp_controller *controller);extern int cpci_hp_unregister_controller (struct cpci_hp_controller *controller);extern int cpci_hp_register_bus (struct pci_bus *bus,u8 first,u8 last);
drivers/pci/hotplug/cpci_hotplug_core.c +29 -47
216 lines not on this page · raw message
drivers/pci/hotplug/cpci_hotplug_pci.c +2 -2
@@ -209,7 +209,7 @@ int cpci_led_on(struct slot* slot) hs_cap + 2, hs_csr)) {err ("Could not set LOO for slot %s" , - slot->hotplug_slot->name); +hotplug_slot_name (slot->hotplug_slot));return -ENODEV ; } }
@@ -238,7 +238,7 @@ int cpci_led_off(struct slot* slot) hs_cap + 2, hs_csr)) {err ("Could not clear LOO for slot %s" , - slot->hotplug_slot->name); +hotplug_slot_name (slot->hotplug_slot));return -ENODEV ; } }
PATCH v4 7/15 PCI: cpqphp: stop managing hotplug_slot->name
In reply to Alex ChiangWe no longer need to manage our version of hotplug_slot->name since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would like, and let the core take care of the rest.
---
drivers/pci/hotplug/cpqphp.h | 13 ++++------- drivers/pci/hotplug/cpqphp_core.c | 42 +++++++++++++++++-------------------- 2 files changed, 24 insertions(+), 31 deletions(-)
drivers/pci/hotplug/cpqphp.h +5 -8
@@ -449,6 +449,11 @@ extern u8 cpqhp_disk_irq;/* inline functions */ +static inline char *slot_name (struct slot *slot) +{ +return hotplug_slot_name (slot->hotplug_slot); +} +/* * return_resource *
@@ -696,14 +701,6 @@ static inline int get_presence_status(struct controller *ctrl, struct slot *slotreturn presence_save; } -#define SLOT_NAME_SIZE 10 - -static inline void make_slot_name (char *buffer,int buffer_size,struct slot *slot) -{ -snprintf (buffer, buffer_size,"%d" , slot->number); -} - -static inline int wait_for_ctrl_irq (struct controller *ctrl) {DECLARE_WAITQUEUE (wait, current);
drivers/pci/hotplug/cpqphp_core.c +19 -23
152 lines not on this page · raw message
PATCH v4 8/15 PCI: fakephp: remove 'name' parameter
In reply to Alex ChiangRemove 'name' from fakephp's struct dummy_slot, as the PCI core will now manage our slot name for us.
---
drivers/pci/hotplug/fakephp.c | 19 ++++++++++--------- 1 files changed, 10 insertions(+), 9 deletions(-)
drivers/pci/hotplug/fakephp.c +10 -9
@@ -66,7 +66,6 @@ struct dummy_slot {struct pci_dev *dev;struct work_struct remove_work;unsigned long removed; -char name[8 ]; };static int debug;
@@ -96,10 +95,13 @@ static void dummy_release(struct hotplug_slot *slot)kfree (dslot); } +#define SLOT_NAME_SIZE 8 +static int add_slot (struct pci_dev *dev) {struct dummy_slot *dslot;struct hotplug_slot *slot; +char name[SLOT_NAME_SIZE ];int retval = -ENOMEM ;static int count =1 ;
@@ -119,20 +121,18 @@ static int add_slot(struct pci_dev *dev)if (!dslot) goto error_info; - slot->name = dslot->name; -snprintf (slot->name,sizeof (dslot->name),"fake%d" , count++); -dbg ("slot->name = %s\n" , slot->name); +snprintf (name,SLOT_NAME_SIZE ,"fake%d" , count++); slot->ops = &dummy_hotplug_slot_ops; slot->release = &dummy_release; slot->private = dslot; - retval =pci_hp_register (slot, dev->bus,PCI_SLOT (dev->devfn), - slot->name); + retval =pci_hp_register (slot, dev->bus,PCI_SLOT (dev->devfn), name);if (retval) {err ("pci_hp_register failed with error %d\n" , retval); goto error_dslot; } +dbg ("slot->name = %s\n" ,hotplug_slot_name (slot)); dslot->slot = slot; dslot->dev =pci_dev_get (dev);list_add (&dslot->node, &slot_list);
@@ -168,10 +168,11 @@ static void remove_slot(struct dummy_slot *dslot) {int retval; -dbg ("removing slot %s\n" , dslot->slot->name); +dbg ("removing slot %s\n" ,hotplug_slot_name (dslot->slot)); retval =pci_hp_deregister (dslot->slot);if (retval) -err ("Problem unregistering a slot %s\n" , dslot->slot->name); +err ("Problem unregistering a slot %s\n" , +hotplug_slot_name (dslot->slot)); }/* called from the single-threaded workqueue handler to remove a slot */
@@ -309,7 +310,7 @@ static int disable_slot(struct hotplug_slot *slot)return -ENODEV ; dslot = slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,hotplug_slot_name (slot));for (func =7 ; func >=0 ; func--) { dev =pci_get_slot (dslot->dev->bus, dslot->dev->devfn + func);
PATCH v4 9/15 PCI: ibmphp: stop managing hotplug_slot->name
In reply to Alex ChiangWe no longer need to manage our version of hotplug_slot->name since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would like, and let the core take care of the rest.
Additionally, slightly rearrange the members of struct slot so they are naturally aligned to eliminate holes.
---
drivers/pci/hotplug/ibmphp.h | 5 ++--- drivers/pci/hotplug/ibmphp_ebda.c | 20 +++++++------------- 2 files changed, 9 insertions(+), 16 deletions(-)
drivers/pci/hotplug/ibmphp.h +2 -3
@@ -707,17 +707,16 @@ struct slot {u8 device;u8 number;u8 real_physical_slot_num; -char name[100 ];u32 capabilities;u8 supported_speed;u8 supported_bus_mode; +u8 flag;/* this is for disable slot and polling */ +u8 ctlr_index;struct hotplug_slot *hotplug_slot;struct controller *ctrl;struct pci_func *func;u8 irq[4 ]; -u8 flag;/* this is for disable slot and polling */ int bit_mode;/* 0 = 32, 1 = 64 */ -u8 ctlr_index;struct bus_info *bus_on;struct list_head ibm_slot_list;u8 status;
drivers/pci/hotplug/ibmphp_ebda.c +7 -13
@@ -587,11 +587,14 @@ static u8 calculate_first_slot (u8 slot_num)return first_slot +1 ; } + +#define SLOT_NAME_SIZE 30 +static char *create_file_name (struct slot * slot_cur) {struct opt_rio *opt_vg_ptr =NULL ;struct opt_rio_lo *opt_lo_ptr =NULL ; -static char str[30 ]; +static char str[SLOT_NAME_SIZE ];int which =0 ;/* rxe = 1, chassis = 0 */ u8 number =1 ;/* either chassis or rxe # */ u8 first_slot =1 ;
@@ -703,7 +706,6 @@ static void release_slot(struct hotplug_slot *hotplug_slot) slot = hotplug_slot->private;kfree (slot->hotplug_slot->info); -kfree (slot->hotplug_slot->name);kfree (slot->hotplug_slot); slot->ctrl =NULL ; slot->bus_on =NULL ;
@@ -734,6 +736,7 @@ static int __init ebda_rsrc_controller (void)struct bus_info *bus_info_ptr1, *bus_info_ptr2;int rc;struct slot *tmp_slot; +char name[SLOT_NAME_SIZE ]; addr = hpc_list_ptr->phys_addr;for (ctlr =0 ; ctlr < hpc_list_ptr->num_ctlrs; ctlr++) {
@@ -897,12 +900,6 @@ static int __init ebda_rsrc_controller (void) goto error_no_hp_info; } - hp_slot_ptr->name =kmalloc (30 ,GFP_KERNEL ); -if (!hp_slot_ptr->name) { - rc = -ENOMEM ; - goto error_no_hp_name; - } - tmp_slot =kzalloc (sizeof (*tmp_slot),GFP_KERNEL );if (!tmp_slot) { rc = -ENOMEM ;
@@ -964,10 +961,9 @@ static int __init ebda_rsrc_controller (void) }/* each hpc */ list_for_each_entry (tmp_slot, &ibmphp_slot_head, ibm_slot_list) { -snprintf (tmp_slot->hotplug_slot->name,30 ,"%s" ,create_file_name (tmp_slot)); +snprintf (name,SLOT_NAME_SIZE ,"%s" ,create_file_name (tmp_slot));pci_hp_register (tmp_slot->hotplug_slot, -pci_find_bus (0 , tmp_slot->bus), tmp_slot->device, - tmp_slot->hotplug_slot->name); +pci_find_bus (0 , tmp_slot->bus), tmp_slot->device, name); }print_ebda_hpc ();
@@ -977,8 +973,6 @@ static int __init ebda_rsrc_controller (void) error:kfree (hp_slot_ptr->private); error_no_slot: -kfree (hp_slot_ptr->name); -error_no_hp_name:kfree (hp_slot_ptr->info); error_no_hp_info:kfree (hp_slot_ptr);
PATCH v4 10/15 PCI: pciehp: remove 'name' parameter
In reply to Alex ChiangWe do not need to manage our own name parameter, especially since the PCI core can change it on our behalf, in the case of duplicate slot names.
Remove 'name' from pciehp's version of struct slot, and remove unused 'task_list' as well.
---
drivers/pci/hotplug/pciehp.h | 9 ++++-- drivers/pci/hotplug/pciehp_core.c | 33 ++++++++++++----------- drivers/pci/hotplug/pciehp_ctrl.c | 53 ++++++++++++++++++++----------------- drivers/pci/hotplug/pciehp_hpc.c | 1 - 4 files changed, 52 insertions(+), 44 deletions(-)
drivers/pci/hotplug/pciehp.h +6 -3
@@ -74,15 +74,13 @@ extern struct workqueue_struct *pciehp_wq;struct slot {u8 bus;u8 device; -u32 number;u8 state; -struct timer_list task_event;u8 hp_slot; +u32 number;struct controller *ctrl;struct hpc_ops *hpc_ops;struct hotplug_slot *hotplug_slot;struct list_head slot_list; -char name[SLOT_NAME_SIZE ];unsigned long last_emi_toggle;struct delayed_work work;/* work for button event */ struct mutex lock;
@@ -175,6 +173,11 @@ int pciehp_enable_slot(struct slot *p_slot);int pciehp_disable_slot (struct slot *p_slot);int pcie_enable_notification (struct controller *ctrl); +static inline const char *slot_name (struct slot *slot) +{ +return hotplug_slot_name (slot->hotplug_slot); +} +static inline struct slot *pciehp_find_slot (struct controller *ctrl,u8 device) {struct slot *slot;
drivers/pci/hotplug/pciehp_core.c +17 -16
@@ -185,7 +185,7 @@ static void release_slot(struct hotplug_slot *hotplug_slot)struct slot *slot = hotplug_slot->private;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,hotplug_slot_name (hotplug_slot));kfree (hotplug_slot->info);kfree (hotplug_slot);
@@ -196,6 +196,7 @@ static int init_slots(struct controller *ctrl)struct slot *slot;struct hotplug_slot *hotplug_slot;struct hotplug_slot_info *info; +char name[SLOT_NAME_SIZE ];int retval = -ENOMEM ;list_for_each_entry (slot, &ctrl->slot_list, slot_list) {
@@ -209,15 +210,11 @@ static int init_slots(struct controller *ctrl)/* register this slot with the hotplug pci core */ hotplug_slot->info = info; - hotplug_slot->name = slot->name; hotplug_slot->private = slot; hotplug_slot->release = &release_slot; hotplug_slot->ops = &pciehp_hotplug_slot_ops; -get_power_status (hotplug_slot, &info->power_status); -get_attention_status (hotplug_slot, &info->attention_status); -get_latch_status (hotplug_slot, &info->latch_status); -get_adapter_status (hotplug_slot, &info->adapter_status); slot->hotplug_slot = hotplug_slot; +snprintf (name,SLOT_NAME_SIZE ,"%u" , slot->number); ctrl_dbg(ctrl, "Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n", slot->bus, slot->device,
@@ -225,12 +222,16 @@ static int init_slots(struct controller *ctrl) retval =pci_hp_register (hotplug_slot, ctrl->pci_dev->subordinate, slot->device, - slot->name); + name);if (retval) {ctrl_err (ctrl,"pci_hp_register failed with error %d\n" , retval); goto error_info; } +get_power_status (hotplug_slot, &info->power_status); +get_attention_status (hotplug_slot, &info->attention_status); +get_latch_status (hotplug_slot, &info->latch_status); +get_adapter_status (hotplug_slot, &info->adapter_status);/* create additional sysfs entries */ if (EMI (ctrl)) { retval = sysfs_create_file(&hotplug_slot->pci_slot->kobj,
@@ -273,7 +274,7 @@ static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)struct slot *slot = hotplug_slot->private;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); hotplug_slot->info->attention_status = status;
@@ -289,7 +290,7 @@ static int enable_slot(struct hotplug_slot *hotplug_slot)struct slot *slot = hotplug_slot->private;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot));return pciehp_sysfs_enable_slot (slot); }
@@ -300,7 +301,7 @@ static int disable_slot(struct hotplug_slot *hotplug_slot)struct slot *slot = hotplug_slot->private;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot));return pciehp_sysfs_disable_slot (slot); }
@@ -311,7 +312,7 @@ static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)int retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_power_status (slot, value);if (retval <0 )
@@ -326,7 +327,7 @@ static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)int retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_attention_status (slot, value);if (retval <0 )
@@ -341,7 +342,7 @@ static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)int retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_latch_status (slot, value);if (retval <0 )
@@ -356,7 +357,7 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)int retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_adapter_status (slot, value);if (retval <0 )
@@ -372,7 +373,7 @@ static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,int retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_max_bus_speed (slot, value);if (retval <0 )
@@ -387,7 +388,7 @@ static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speint retval;ctrl_dbg (slot->ctrl,"%s - physical_slot = %s\n" , - __func__, hotplug_slot->name); + __func__,slot_name (slot)); retval = slot->hpc_ops->get_cur_bus_speed (slot, value);if (retval <0 )
drivers/pci/hotplug/pciehp_ctrl.c +29 -24
178 lines not on this page · raw message
drivers/pci/hotplug/pciehp_hpc.c +0 -1
@@ -1061,7 +1061,6 @@ static int pcie_init_slot(struct controller *ctrl) slot->device = ctrl->slot_device_offset + slot->hp_slot; slot->hpc_ops = ctrl->hpc_ops; slot->number = ctrl->first_slot; -snprintf (slot->name,SLOT_NAME_SIZE ,"%d" , slot->number);mutex_init (&slot->lock);INIT_DELAYED_WORK (&slot->work, pciehp_queue_pushbutton_work);list_add (&slot->slot_list, &ctrl->slot_list);
PATCH v4 11/15 PCI: rpaphp: kmalloc/kfree slot->name directly
In reply to Alex Chiangrpaphp tends to use slot->name directly everywhere, and doesn't ever need slot->hotplug_slot->name.
struct hotplug_slot->name is going away, so convert rpaphp directly manipulate its own slot->name everywhere, and don't bother touching slot->hotplug_slot->name.
---
drivers/pci/hotplug/rpaphp_slot.c | 7 +++---- 1 files changed, 3 insertions(+), 4 deletions(-)
drivers/pci/hotplug/rpaphp_slot.c +3 -4
@@ -43,7 +43,7 @@ static void rpaphp_release_slot(struct hotplug_slot *hotplug_slot)void dealloc_slot_struct (struct slot *slot) {kfree (slot->hotplug_slot->info); -kfree (slot->hotplug_slot->name); +kfree (slot->name);kfree (slot->hotplug_slot);kfree (slot); }
@@ -63,10 +63,9 @@ struct slot *alloc_slot_struct(struct device_node *dn, GFP_KERNEL);if (!slot->hotplug_slot->info) goto error_hpslot; - slot->hotplug_slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL ); -if (!slot->hotplug_slot->name) + slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL ); +if (!slot->name) goto error_info; - slot->name = slot->hotplug_slot->name;strcpy (slot->name, drc_name); slot->dn = dn; slot->index = drc_index;
Re: [PATCH v4 11/15] PCI: rpaphp: kmalloc/kfree slot->name directly
drivers/pci/hotplug/rpaphp_slot.c struct slot *alloc_slot_struct(struct device_node *dn, · line 69
Quoted 11 lines · Alex Chiang
drivers/pci/hotplug/rpaphp_slot.c +2
-3@@ -63,10 +63,9 @@ struct slot *alloc_slot_struct(struct device_node *dn, GFP_KERNEL);if (!slot->hotplug_slot->info) goto error_hpslot; - slot->hotplug_slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL ); -if (!slot->hotplug_slot->name) + slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL ); +if (!slot->name) goto error_info; - slot->name = slot->hotplug_slot->name;strcpy (slot->name, drc_name);
Minor nit: you could use kstrdup() here.
Re: [PATCH v4 11/15] PCI: rpaphp: kmalloc/kfree slot->name directly
* Pekka Enberg <[email protected]>:
Quoted 6 lines · Alex Chiang
Quoted 5 lines
drivers/pci/hotplug/rpaphp_slot.c +0
-1@@ -63,10 +63,9 @@ struct slot *alloc_slot_struct(struct device_node *dn, GFP_KERNEL);if (!slot->hotplug_slot->info) goto error_hpslot; - slot->hotplug_slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL );
Quoted 8 lines
drivers/pci/hotplug/rpaphp_slot.c struct slot *alloc_slot_struct(struct device_node *dn, · line 69
Quoted 6 lines
drivers/pci/hotplug/rpaphp_slot.c +2
-2-if (!slot->hotplug_slot->name) + slot->name =kmalloc (strlen (drc_name) +1 ,GFP_KERNEL ); +if (!slot->name) goto error_info; - slot->name = slot->hotplug_slot->name;strcpy (slot->name, drc_name);Minor nit: you could use
kstrdup()here.
Good call, I've made a change, thanks.
/ac
PATCH v4 12/15 PCI: SGI Hotplug: stop managing bss_hotplug_slot->name
In reply to Alex ChiangWe no longer need to manage our version of hotplug_slot->name since the PCI and hotplug core manage it on our behalf.
Update the sn_hp_slot_private_alloc() interface to fill in the correct name for us, as that function already has all the parameters needed to determine the name.
---
drivers/pci/hotplug/sgi_hotplug.c | 19 ++++++------------- 1 files changed, 6 insertions(+), 13 deletions(-)
drivers/pci/hotplug/sgi_hotplug.c +6 -13
@@ -161,7 +161,8 @@ static int sn_pci_bus_valid(struct pci_bus *pci_bus) }static int sn_hp_slot_private_alloc (struct hotplug_slot *bss_hotplug_slot, -struct pci_bus *pci_bus,int device) +struct pci_bus *pci_bus,int device, +char *name) {struct pcibus_info *pcibus_info;struct slot *slot;
@@ -173,15 +174,9 @@ static int sn_hp_slot_private_alloc(struct hotplug_slot *bss_hotplug_slot,return -ENOMEM ; bss_hotplug_slot->private = slot; - bss_hotplug_slot->name =kmalloc (SN_SLOT_NAME_SIZE ,GFP_KERNEL ); -if (!bss_hotplug_slot->name) { -kfree (bss_hotplug_slot->private); -return -ENOMEM ; - } - slot->device_num = device; slot->pci_bus = pci_bus; -sprintf (bss_hotplug_slot->name,"%04x:%02x:%02x" , +sprintf (name,"%04x:%02x:%02x" ,pci_domain_nr (pci_bus), ((u16 )pcibus_info->pbi_buscommon.bs_persist_busnum), device +1 );
@@ -608,7 +603,6 @@ static inline int get_power_status(struct hotplug_slot *bss_hotplug_slot,static void sn_release_slot (struct hotplug_slot *bss_hotplug_slot) {kfree (bss_hotplug_slot->info); -kfree (bss_hotplug_slot->name);kfree (bss_hotplug_slot->private);kfree (bss_hotplug_slot); }
@@ -618,6 +612,7 @@ static int sn_hotplug_slot_register(struct pci_bus *pci_bus)int device;struct pci_slot *pci_slot;struct hotplug_slot *bss_hotplug_slot; +char name[SN_SLOT_NAME_SIZE ];int rc =0 ;/*
@@ -645,16 +640,14 @@ static int sn_hotplug_slot_register(struct pci_bus *pci_bus) }if (sn_hp_slot_private_alloc (bss_hotplug_slot, - pci_bus, device)) { + pci_bus, device, name)) { rc = -ENOMEM ; goto alloc_err; } - bss_hotplug_slot->ops = &sn_hotplug_slot_ops; bss_hotplug_slot->release = &sn_release_slot; - rc =pci_hp_register (bss_hotplug_slot, pci_bus, device, - bss_hotplug_slot->name); + rc =pci_hp_register (bss_hotplug_slot, pci_bus, device, name);if (rc) goto register_err;
PATCH v4 13/15 PCI: shcphp: remove 'name' parameter
In reply to Alex ChiangWe do not need to manage our own name parameter, especially since the PCI core can change it on our behalf, in the case of duplicate slot names.
Remove 'name' from shpchp's version of struct slot.
This change also removes the unused struct task_event from the slot structure.
---
drivers/pci/hotplug/shpchp.h | 9 +++++-- drivers/pci/hotplug/shpchp_core.c | 38 ++++++++++++++--------------- drivers/pci/hotplug/shpchp_ctrl.c | 48 +++++++++++++++++++------------------ 3 files changed, 48 insertions(+), 47 deletions(-)
drivers/pci/hotplug/shpchp.h +6 -3
@@ -69,15 +69,13 @@ struct slot {u8 state;u8 presence_save;u8 pwr_save; -struct timer_list task_event; -u8 hp_slot;struct controller *ctrl;struct hpc_ops *hpc_ops;struct hotplug_slot *hotplug_slot;struct list_head slot_list; -char name[SLOT_NAME_SIZE ];struct delayed_work work;/* work for button event */ struct mutex lock; +u8 hp_slot; };struct event_info {
@@ -169,6 +167,11 @@ extern void cleanup_slots(struct controller *ctrl);extern void shpchp_queue_pushbutton_work (struct work_struct *work);extern int shpc_init (struct controller *ctrl,struct pci_dev *pdev); +static inline const char *slot_name (struct slot *slot) +{ +return hotplug_slot_name (slot->hotplug_slot); +} +#ifdef CONFIG_ACPI #include <linux/pci-acpi.h> static inline int get_hp_params_from_firmware(struct pci_dev *dev,
drivers/pci/hotplug/shpchp_core.c +18 -20
@@ -89,7 +89,7 @@ static void release_slot(struct hotplug_slot *hotplug_slot) {struct slot *slot = hotplug_slot->private; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));kfree (slot->hotplug_slot->info);kfree (slot->hotplug_slot);
@@ -101,6 +101,7 @@ static int init_slots(struct controller *ctrl)struct slot *slot;struct hotplug_slot *hotplug_slot;struct hotplug_slot_info *info; +char name[SLOT_NAME_SIZE ];int retval = -ENOMEM ;int i;
@@ -119,8 +120,6 @@ static int init_slots(struct controller *ctrl) goto error_hpslot; hotplug_slot->info = info; - hotplug_slot->name = slot->name; - slot->hp_slot = i; slot->ctrl = ctrl; slot->bus = ctrl->pci_dev->subordinate->number;
@@ -133,25 +132,24 @@ static int init_slots(struct controller *ctrl)/* register this slot with the hotplug pci core */ hotplug_slot->private = slot; hotplug_slot->release = &release_slot; -snprintf (slot->name,SLOT_NAME_SIZE ,"%d" , slot->number); +snprintf (name,SLOT_NAME_SIZE ,"%d" , slot->number); hotplug_slot->ops = &shpchp_hotplug_slot_ops; -get_power_status (hotplug_slot, &info->power_status); -get_attention_status (hotplug_slot, &info->attention_status); -get_latch_status (hotplug_slot, &info->latch_status); -get_adapter_status (hotplug_slot, &info->adapter_status); -dbg ("Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n" , slot->bus, slot->device, slot->hp_slot, slot->number, ctrl->slot_device_offset); retval =pci_hp_register (slot->hotplug_slot, - ctrl->pci_dev->subordinate, slot->device, - hotplug_slot->name); + ctrl->pci_dev->subordinate, slot->device, name);if (retval) {err ("pci_hp_register failed with error %d\n" , retval); goto error_info; } +get_power_status (hotplug_slot, &info->power_status); +get_attention_status (hotplug_slot, &info->attention_status); +get_latch_status (hotplug_slot, &info->latch_status); +get_adapter_status (hotplug_slot, &info->adapter_status); +list_add (&slot->slot_list, &ctrl->slot_list); }
@@ -189,7 +187,7 @@ static int set_attention_status (struct hotplug_slot *hotplug_slot, u8 status) {struct slot *slot =get_slot (hotplug_slot); -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); hotplug_slot->info->attention_status = status; slot->hpc_ops->set_attention_status (slot, status);
@@ -201,7 +199,7 @@ static int enable_slot (struct hotplug_slot *hotplug_slot) {struct slot *slot =get_slot (hotplug_slot); -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));return shpchp_sysfs_enable_slot (slot); }
@@ -210,7 +208,7 @@ static int disable_slot (struct hotplug_slot *hotplug_slot) {struct slot *slot =get_slot (hotplug_slot); -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot));return shpchp_sysfs_disable_slot (slot); }
@@ -220,7 +218,7 @@ static int get_power_status (struct hotplug_slot *hotplug_slot, u8 *value)struct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_power_status (slot, value);if (retval <0 )
@@ -234,7 +232,7 @@ static int get_attention_status (struct hotplug_slot *hotplug_slot, u8 *value)struct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_attention_status (slot, value);if (retval <0 )
@@ -248,7 +246,7 @@ static int get_latch_status (struct hotplug_slot *hotplug_slot, u8 *value)struct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_latch_status (slot, value);if (retval <0 )
@@ -262,7 +260,7 @@ static int get_adapter_status (struct hotplug_slot *hotplug_slot, u8 *value)struct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_adapter_status (slot, value);if (retval <0 )
@@ -277,7 +275,7 @@ static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,struct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_max_bus_speed (slot, value);if (retval <0 )
@@ -291,7 +289,7 @@ static int get_cur_bus_speed (struct hotplug_slot *hotplug_slot, enum pci_bus_spstruct slot *slot =get_slot (hotplug_slot);int retval; -dbg ("%s - physical_slot = %s\n" , __func__, hotplug_slot->name); +dbg ("%s - physical_slot = %s\n" , __func__,slot_name (slot)); retval = slot->hpc_ops->get_cur_bus_speed (slot, value);if (retval <0 )
drivers/pci/hotplug/shpchp_ctrl.c +24 -24
166 lines not on this page · raw message
PATCH v4 14/15 PCI: Hotplug core: remove 'name'
In reply to Alex ChiangNow that the PCI core manages the 'name' for each individual hotplug driver, and all drivers (except rpaphp) have been converted to use hotplug_slot_name(), there is no need for the PCI hotplug core to drag around its own copy of name either.
---
drivers/pci/hotplug/pci_hotplug_core.c | 6 +++--- include/linux/pci_hotplug.h | 3 --- 2 files changed, 3 insertions(+), 6 deletions(-)
drivers/pci/hotplug/pci_hotplug_core.c +3 -3
@@ -534,7 +534,7 @@ static struct hotplug_slot *get_slot_from_name (const char *name)spin_lock (&pci_hotplug_slot_list_lock); list_for_each (tmp, &pci_hotplug_slot_list) { slot = list_entry (tmp, struct hotplug_slot, slot_list); -if (strcmp (slot->name, name) ==0 ) +if (strcmp (hotplug_slot_name (slot), name) ==0 ) goto out; } slot =NULL ;
@@ -632,7 +632,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)if (!hotplug)return -ENODEV ; - temp =get_slot_from_name (hotplug->name); + temp =get_slot_from_name (hotplug_slot_name (hotplug));if (temp != hotplug)return -ENODEV ;
@@ -643,7 +643,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) slot = hotplug->pci_slot;fs_remove_slot (slot); -dbg ("Removed slot %s from the list\n" , hotplug->name); +dbg ("Removed slot %s from the list\n" ,hotplug_slot_name (hotplug)); hotplug->release (hotplug); slot->hotplug =NULL ;
include/linux/pci_hotplug.h +0 -3
@@ -142,8 +142,6 @@ struct hotplug_slot_info {/** * struct hotplug_slot - used to register a physical slot with the hotplug pci core -* @name: the name of the slot being registered. This string must -* be unique amoung slots registered on this system. * @ops: pointer to the &struct hotplug_slot_ops to be used for this slot * @info: pointer to the &struct hotplug_slot_info for the initial values for * this slot.
@@ -153,7 +151,6 @@ struct hotplug_slot_info {* needs. */ struct hotplug_slot { -char *name;struct hotplug_slot_ops *ops;struct hotplug_slot_info *info;void (*release) (struct hotplug_slot *slot);
PATCH v4 15/15 PCI Hotplug: fakephp: add duplicate slot name debugging
In reply to Alex ChiangThe PCI core now manages slot names on behalf of slot detection and slot hotplug drivers, including the handling of duplicate slot names.
We can use the fakephp driver to help test the new functionality. Add a 'dup_slots' module param to force fakephp to create multiple slots with the same name. We can then verify that the PCI core correctly renamed the slots.
sapphire:/sys/bus/pci/slots # modprobe fakephp dup_slots sapphire:/sys/bus/pci/slots # ls
fake fake-10 fake-3 fake-5 fake-7 fake-9
fake-1 fake-2 fake-4 fake-6 fake-8
---
drivers/pci/hotplug/fakephp.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-)
drivers/pci/hotplug/fakephp.c +8 -2
@@ -69,6 +69,7 @@ struct dummy_slot { };static int debug; +static int dup_slots;static LIST_HEAD (slot_list);static struct workqueue_struct *dummyphp_wq;
@@ -121,7 +122,11 @@ static int add_slot(struct pci_dev *dev)if (!dslot) goto error_info; -snprintf (name,SLOT_NAME_SIZE ,"fake%d" , count++); +if (dup_slots) +snprintf (name,SLOT_NAME_SIZE ,"fake" ); +else +snprintf (name,SLOT_NAME_SIZE ,"fake%d" , count++); +dbg ("slot->name = %s\n" , name); slot->ops = &dummy_hotplug_slot_ops; slot->release = &dummy_release; slot->private = dslot;
@@ -375,4 +380,5 @@ MODULE_DESCRIPTION(DRIVER_DESC);MODULE_LICENSE ("GPL" );module_param (debug, bool,S_IRUGO |S_IWUSR );MODULE_PARM_DESC (debug,"Debugging mode enabled or not" ); - +module_param (dup_slots, bool,S_IRUGO |S_IWUSR ); +MODULE_PARM_DESC (dup_slots,"Force duplicate slot names for debugging" );
Hi Alex-san,
I have some ideas and made some patches for comments I sent about your [PATCH v4 02/15] and [PATCH v4 03/15]. Please take a look. There are three patches.
- [01/03] Sample patch for [PATCH v4 02/15]
- [02/03] Sample patch for [PATCH v4 03/15] NOTE:This doesn't target the comment about changing exported symbol name.
- [03/03] Sample patch for [PATCH v4 14/15]
This is needed because above two patches make your [PATCH v4 14/15] can not be applied.
Note: I made those patches as replacement of your corresponding ones. So those patches are NOT for applying on top your original patches.
Thanks,
Kenji Kaneshige
Quoted 94 lines · Alex Chiang
Hi all,
This is v4 of the series that implements a series of changes that allows the PCI core to manage slot names, rather than individual hotplug drivers.
Thank you to Kenji-san and Taku-san for testing and finding my bugs. Thanks to Willy for helping me out with the locking issues in
pci_hp_register.Again, I have tested by loading
pci_slot, acpiphp, and fakephp in various combinations, and using the new dup_slots=1 param to fakephp. I also had:
CONFIG_DEBUG_SPINLOCK=yCONFIG_DEBUG_MUTEXES=yCONFIG_DEBUG_SPINLOCK_SLEEP=yand didn't see any complaints.
This series applies against Jesse's linux-next branch. I just fetched his branch and peeked at it, and based on the log, my series _should_ apply with minimal fuzz (but I didn't do a rebase because I didn't think to check until writing this mail ;).
It would be great if folks could give one last (hopefully!) review.
Thanks.
/ac
v3 -> v4:
- Do not accesshotplug_slot_name()before name initialization
- Serialize pci_hp_register/deregisterv2 -> v3:
- incorporate Willy's code review comments
- fix possible memory leak, pointed out by Rolf Eike Beer
- make false name collision detection work for empty slots
- add 'dup_slots'module_paramto fakephp to help debug all this ;)v1 -> v2:
- fix possible false name collisions---
Alex Chiang (15):
PCI Hotplug: fakephp: add duplicate slot name debugging
PCI: Hotplug core: remove 'name'
PCI: shcphp: remove 'name' parameter
PCI: SGI Hotplug: stop managingbss_hotplug_slot->name
PCI: rpaphp: kmalloc/kfreeslot->namedirectly
PCI: pciehp: remove 'name' parameter
PCI: ibmphp: stop managinghotplug_slot->name
PCI: fakephp: remove 'name' parameter
PCI: cpqphp: stop managinghotplug_slot->name
PCI:cpci_hotplug: stop managinghotplug_slot->name
PCI: acpiphp: remove 'name' parameter
PCI, PCI Hotplug: introduceslot_namehelpers
PCI: prevent duplicate slot names
PCI Hotplug: serialize pci_hp_register/deregister PCI Hotplug core: add 'name' parampci_hp_registerinterfacedrivers/pci/hotplug/acpiphp.h | 9 +- drivers/pci/hotplug/acpiphp_core.c | 32 +++-- drivers/pci/hotplug/cpci_hotplug.h | 6 + drivers/pci/hotplug/cpci_hotplug_core.c | 75 +++++-------- drivers/pci/hotplug/cpci_hotplug_pci.c | 4 - drivers/pci/hotplug/cpqphp.h | 13 +- drivers/pci/hotplug/cpqphp_core.c | 43 +++---- drivers/pci/hotplug/fakephp.c | 26 +++- drivers/pci/hotplug/ibmphp.h | 5 - drivers/pci/hotplug/ibmphp_ebda.c | 19 +-- drivers/pci/hotplug/pci_hotplug_core.c | 68 ++++++------ drivers/pci/hotplug/pciehp.h | 9 +- drivers/pci/hotplug/pciehp_core.c | 49 +++----- drivers/pci/hotplug/pciehp_ctrl.c | 53 +++++---- drivers/pci/hotplug/pciehp_hpc.c | 1 drivers/pci/hotplug/rpaphp_slot.c | 9 +- drivers/pci/hotplug/sgi_hotplug.c | 18 +-- drivers/pci/hotplug/shpchp.h | 9 +- drivers/pci/hotplug/shpchp_core.c | 52 +++------ drivers/pci/hotplug/shpchp_ctrl.c | 48 ++++---- drivers/pci/slot.c | 181 +++++++++++++++++++++++-------- include/linux/pci.h | 9 +- include/linux/pci_hotplug.h | 11 +- 23 files changed, 407 insertions(+), 342 deletions(-)--
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PATCH 1/3 Sample patch for [PATCH v4 02/15]
---drivers/pci/hotplug/pci_hotplug_core.c | 49 +++++++++++++++++----------------
1 file changed, 26 insertions(+), 23 deletions(-)
drivers/pci/hotplug/pci_hotplug_core.c +0 -0
@@ -37,6 +37,7 @@
#include <linux/init.h>
#include <linux/mount.h>
#include <linux/namei.h>
+#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <asm/uaccess.h>
@@ -61,7 +62,7 @@ static int debug; //////////////////////////////////////////////////////////////////
static LIST_HEAD(pci_hotplug_slot_list); -static DEFINE_SPINLOCK(pci_hotplug_slot_list_lock); +static DEFINE_MUTEX(pci_hp_mutex);
/* these strings match up with the values in pci_bus_speed */ static char *pci_bus_speed_strings[] = {
@@ -530,16 +531,12 @@ static struct hotplug_slot *get_slot_fro
struct hotplug_slot *slot; struct list_head *tmp;
- spin_lock(&pci_hotplug_slot_list_lock);
list_for_each (tmp, &pci_hotplug_slot_list) {
slot = list_entry (tmp, struct hotplug_slot, slot_list);
if (strcmp(slot->name, name) == 0)
- goto out;
+ return slot;
}- slot = NULL;
-out:
- spin_unlock(&pci_hotplug_slot_list_lock);
- return slot;
+ return NULL;
}
/**
@@ -570,9 +567,13 @@ int pci_hp_register(struct hotplug_slot
return -EINVAL; }
+ mutex_lock(&pci_hp_mutex);
+
/* Check if we have already registered a slot with the same name. */
- if (get_slot_from_name(name))
- return -EEXIST;
+ if (get_slot_from_name(name)) {
+ result = -EEXIST;
+ goto out;
+ }
/* * No problems if we call this interface from both ACPI_PCI_SLOT @@ -580,13 +581,13 @@ int pci_hp_register(struct hotplug_slot * pci_slot, the interface will simply bump the refcount. */ pci_slot = pci_create_slot(bus, slot_nr, name);
- if (IS_ERR(pci_slot))
- return PTR_ERR(pci_slot);
+ if ((result = IS_ERR(pci_slot)))
+ goto out;
if (pci_slot->hotplug) {
dbg("%s: already claimed\n", __func__);
- pci_destroy_slot(pci_slot);
- return -EBUSY;
+ result = -EBUSY;
+ goto cleanup;
}
slot->pci_slot = pci_slot;
@@ -597,21 +598,21 @@ int pci_hp_register(struct hotplug_slot
*/
if (strcmp(kobject_name(&pci_slot->kobj), name)) {
result = kobject_rename(&pci_slot->kobj, name);- if (result) {
- pci_destroy_slot(pci_slot);
- return result;
- }
+ if (result)
+ goto cleanup; }
- spin_lock(&pci_hotplug_slot_list_lock); list_add(&slot->slot_list, &pci_hotplug_slot_list);
- spin_unlock(&pci_hotplug_slot_list_lock);
result = fs_add_slot(pci_slot);
kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
dbg("Added slot %s to the list\n", name);
-
+out:
+ mutex_unlock(&pci_hp_mutex);
return result;+cleanup:
+ pci_destroy_slot(pci_slot);
+ goto out;
}
/**
@@ -631,13 +632,14 @@ int pci_hp_deregister(struct hotplug_slo
if (!hotplug) return -ENODEV;
+ mutex_lock(&pci_hp_mutex);
temp = get_slot_from_name(hotplug->name);
- if (temp != hotplug)
+ if (temp != hotplug) {
+ mutex_unlock(&pci_hp_mutex);
return -ENODEV;+ }
- spin_lock(&pci_hotplug_slot_list_lock); list_del(&hotplug->slot_list);
- spin_unlock(&pci_hotplug_slot_list_lock);
slot = hotplug->pci_slot; fs_remove_slot(slot); @@ -646,6 +648,7 @@ int pci_hp_deregister(struct hotplug_slo hotplug->release(hotplug); slot->hotplug = NULL; pci_destroy_slot(slot);
+ mutex_unlock(&pci_hp_mutex);
return 0; }
PATCH 2/3 Sample patch for [PATCH v4 03/15]
In reply to Kenji KaneshigeNOTE:This doesn't target the comment about changing exported symbol name.
---
drivers/pci/hotplug/pci_hotplug_core.c | 18 +--- drivers/pci/hotplug/pciehp_core.c | 15 ---- drivers/pci/hotplug/shpchp_core.c | 15 ---- drivers/pci/slot.c | 123 ++++++++++++++++++++++++++------- include/linux/pci.h | 4 - 5 files changed, 107 insertions(+), 68 deletions(-)
drivers/pci/hotplug/pciehp_core.c +0 -0
@@ -196,7 +196,6 @@ static int init_slots(struct controller
struct slot *slot;
struct hotplug_slot *hotplug_slot;
struct hotplug_slot_info *info;
- int len, dup = 1;
int retval = -ENOMEM;
list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
@@ -223,25 +222,11 @@ static int init_slots(struct controller
ctrl_dbg(ctrl, "Registering bus=%x dev=%x hp_slot=%x sun=%x "
"slot_device_offset=%x\n", slot->bus, slot->device,
slot->hp_slot, slot->number, ctrl->slot_device_offset);
-duplicate_name:
retval = pci_hp_register(hotplug_slot,
ctrl->pci_dev->subordinate,
slot->device,
slot->name);
if (retval) {- /*
- * If slot N already exists, we'll try to create
- * slot N-1, N-2 ... N-M, until we overflow.
- */
- if (retval == -EEXIST) {
- len = snprintf(slot->name, SLOT_NAME_SIZE,
- "%d-%d", slot->number, dup++);
- if (len < SLOT_NAME_SIZE)
- goto duplicate_name;
- else
- ctrl_err(ctrl, "duplicate slot name "
- "overflow\n");
- }
ctrl_err(ctrl, "pci_hp_register failed with error %d\n", retval); goto error_info;
drivers/pci/hotplug/shpchp_core.c +0 -0
@@ -102,7 +102,7 @@ static int init_slots(struct controller
struct hotplug_slot *hotplug_slot; struct hotplug_slot_info *info; int retval = -ENOMEM;
- int i, len, dup = 1;
+ int i;
for (i = 0; i < ctrl->num_slots; i++) {
slot = kzalloc(sizeof(*slot), GFP_KERNEL);
@@ -144,23 +144,10 @@ static int init_slots(struct controller
dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x "
"slot_device_offset=%x\n", slot->bus, slot->device,
slot->hp_slot, slot->number, ctrl->slot_device_offset);
-duplicate_name:
retval = pci_hp_register(slot->hotplug_slot,
ctrl->pci_dev->subordinate, slot->device,
hotplug_slot->name);
if (retval) {- /*
- * If slot N already exists, we'll try to create
- * slot N-1, N-2 ... N-M, until we overflow.
- */
- if (retval == -EEXIST) {
- len = snprintf(slot->name, SLOT_NAME_SIZE,
- "%d-%d", slot->number, dup++);
- if (len < SLOT_NAME_SIZE)
- goto duplicate_name;
- else
- err("duplicate slot name overflow\n");
- }
err("pci_hp_register failed with error %d\n", retval);
goto error_info;
}include/linux/pci.h +0 -0
@@ -509,8 +509,10 @@ struct pci_bus *pci_add_new_bus(struct p
int busnr); struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr, const char *name);
+struct pci_slot *pci_get_pci_slot(struct pci_bus *parent, int slot_nr); void pci_destroy_slot(struct pci_slot *slot);
-void pci_update_slot_number(struct pci_slot *slot, int slot_nr); +int pci_rename_slot(struct pci_slot *slot, const char *name); +void pci_renumber_slot(struct pci_slot *slot, int slot_nr); int pci_scan_slot(struct pci_bus *bus, int devfn);
struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn); void pci_device_add(struct pci_dev *dev, struct pci_bus *bus);
drivers/pci/hotplug/pci_hotplug_core.c +0 -0
@@ -569,12 +569,6 @@ int pci_hp_register(struct hotplug_slot
mutex_lock(&pci_hp_mutex);
- /* Check if we have already registered a slot with the same name. */
- if (get_slot_from_name(name)) {
- result = -EEXIST;
- goto out;
- }
-
/*
* No problems if we call this interface from both ACPI_PCI_SLOT
* driver and call it here again. If we've already created the
@@ -590,18 +584,14 @@ int pci_hp_register(struct hotplug_slot
goto cleanup; }
- slot->pci_slot = pci_slot;
- pci_slot->hotplug = slot;
-
/* * Allow pcihp drivers to override the ACPI_PCI_SLOT name. */
- if (strcmp(kobject_name(&pci_slot->kobj), name)) {
- result = kobject_rename(&pci_slot->kobj, name);
- if (result)
- goto cleanup;
- }
+ if ((result = pci_rename_slot(pci_slot, name)))
+ goto cleanup;
+ slot->pci_slot = pci_slot;
+ pci_slot->hotplug = slot; list_add(&slot->slot_list, &pci_hotplug_slot_list); result = fs_add_slot(pci_slot);
drivers/pci/slot.c +0 -0
@@ -78,6 +78,46 @@ static struct kobj_type pci_slot_ktype =
.default_attrs = pci_slot_default_attrs,
};
+static char *make_slot_name(struct pci_slot *slot, const char *name) +{
+ char *new_name;
+ int len, max, dup;
+
+ new_name = kstrdup(name, GFP_KERNEL);
+ if (!new_name)
+ return NULL;
+
+ /*
+ * Make sure we hit the realloc case the first time through the
+ * loop. 'len' will be strlen(name) + 3 at that point which is
+ * enough space for "name-X" and the trailing NUL.
+ */
+ len = strlen(name) + 2;
+ max = 1;
+ dup = 1;
+
+ for (;;) {
+ struct kobject *dup_slot;
+ dup_slot = kset_find_obj(pci_slots_kset, new_name);
+ if (!dup_slot)
+ break;
+ kobject_put(dup_slot);
+ if (dup_slot == &slot->kobj)
+ break;
+ if (dup == max) {
+ len++;
+ max *= 10;
+ kfree(new_name);
+ new_name = kmalloc(len, GFP_KERNEL);
+ if (!new_name)
+ break;
+ }
+ sprintf(new_name, "%s-%d", name, dup++);
+ }
+
+ return new_name;
+}
+
/**
* pci_create_slot - create or increment refcount for physical PCI slot
* @parent: struct pci_bus of parent bridge
@@ -89,7 +129,19 @@ static struct kobj_type pci_slot_ktype =
* either return a new &struct pci_slot to the caller, or if the pci_slot
* already exists, its refcount will be incremented.
*
- * Slots are uniquely identified by a @pci_bus, @slot_nr, @name tuple.
+ * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
+ *
+ * The kobject API imposes a restriction on us, and does not allow sysfs
+ * entries with duplicate names. There are known platforms with broken
+ * firmware that assign the same name to multiple slots.
+ *
+ * We workaround these broken platforms by renaming the slots on behalf
+ * of the caller. If firmware assigns name N to multiple slots:
+ *
+ * The first slot is assigned N
+ * The second slot is assigned N-1
+ * The third slot is assigned N-2
+ * etc.
*
* Placeholder slots:
* In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
@@ -98,24 +150,20 @@ static struct kobj_type pci_slot_ktype =
* the slot. In this scenario, the caller may pass -1 for @slot_nr. *
* The following semantics are imposed when the caller passes @slot_nr ==
- * -1. First, the check for existing %struct pci_slot is skipped, as the
- * caller may know about several unpopulated slots on a given %struct
- * pci_bus, and each slot would have a @slot_nr of -1. Uniqueness for
- * these slots is then determined by the @name parameter. We expect
- * kobject_init_and_add() to warn us if the caller attempts to create
- * multiple slots with the same name. The other change in semantics is
+ * -1. First, we no longer check for an existing %struct pci_slot, as there
+ * may be many slots with @slot_nr of -1. The other change in semantics is
* user-visible, which is the 'address' parameter presented in sysfs will
* consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
* %struct pci_bus and bb is the bus number. In other words, the devfn of
* the 'placeholder' slot will not be displayed.
*/
-
struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
const char *name)
{
struct pci_dev *dev;
struct pci_slot *slot;
int err;+ char *slot_name = NULL;
down_write(&pci_bus_sem);
@@ -144,18 +192,23 @@ placeholder:
slot->bus = parent; slot->number = slot_nr; - slot->kobj.kset = pci_slots_kset;
+
+ slot_name = make_slot_name(slot, name);
+ if (!slot_name) {
+ err = -ENOMEM;
+ goto err;
+ }
+
err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
- "%s", name);
+ "%s", slot_name);
if (err) {
- printk(KERN_ERR "Unable to register kobject %s\n", name);
+ printk(KERN_ERR "Unable to register kobject %s\n", slot_name);
goto err;
}
INIT_LIST_HEAD(&slot->list);
list_add(&slot->list, &parent->slots);
-
list_for_each_entry(dev, &parent->devices, bus_list)
if (PCI_SLOT(dev->devfn) == slot_nr)
dev->slot = slot;@@ -166,6 +219,7 @@ placeholder:
out:
up_write(&pci_bus_sem); + kfree(slot_name); return slot; err: kfree(slot);
@@ -175,7 +229,35 @@ placeholder:EXPORT_SYMBOL_GPL(pci_create_slot);
/**
- * pci_update_slot_number - update %struct pci_slot -> number
+ * pci_rename_slot - update %struct pci_slot -> name
+ * @slot - %struct pci_slot to update
+ * @name - new requested name for slot
+ *
+ * Allow caller to safely rename a %struct pci_slot without making
+ * the kobject core complain about duplicate names.
+ */
+int pci_rename_slot(struct pci_slot *slot, const char *name) +{
+ int result = 0;
+ char *slot_name;
+
+ down_write(&pci_bus_sem);
+ slot_name = make_slot_name(slot, name);
+ if (!slot_name) {
+ result = -ENOMEM;
+ goto out;
+ }
+ if (strcmp(kobject_name(&slot->kobj), slot_name))
+ result = kobject_rename(&slot->kobj, slot_name);
+ kfree(slot_name);
+out:
+ up_write(&pci_bus_sem);
+ return result;
+}
+EXPORT_SYMBOL_GPL(pci_rename_slot);
+
+/**
+ * pci_renumber_slot - update %struct pci_slot -> number
* @slot - %struct pci_slot to update
* @slot_nr - new number for slot
*
@@ -183,27 +265,21 @@ EXPORT_SYMBOL_GPL(pci_create_slot);
* created a placeholder slot in pci_create_slot() by passing a -1 as
* slot_nr, to update their %struct pci_slot with the correct @slot_nr. */
-
-void pci_update_slot_number(struct pci_slot *slot, int slot_nr) +void pci_renumber_slot(struct pci_slot *slot, int slot_nr) {
- int name_count = 0;
struct pci_slot *tmp;
down_write(&pci_bus_sem);
list_for_each_entry(tmp, &slot->bus->slots, list) {
WARN_ON(tmp->number == slot_nr);
- if (!strcmp(kobject_name(&tmp->kobj), kobject_name(&slot->kobj)))
- name_count++;
+ goto out;
}-
- if (name_count > 1)
- printk(KERN_WARNING "pci_update_slot_number found %d slots with the same name: %s\n", name_count, kobject_name(&slot->kobj));
-
slot->number = slot_nr; +out: up_write(&pci_bus_sem); }
-EXPORT_SYMBOL_GPL(pci_update_slot_number);
+EXPORT_SYMBOL_GPL(pci_renumber_slot);
/**
* pci_destroy_slot - decrement refcount for physical PCI slot
@@ -213,7 +289,6 @@ EXPORT_SYMBOL_GPL(pci_update_slot_number
* just call kobject_put on its kobj and let our release methods do the
* rest.
*/
-
void pci_destroy_slot(struct pci_slot *slot)
{
pr_debug("%s: dec refcount to %d on %04x:%02x:%02x\n", __func__,PATCH 3/3 Sample patch for [PATCH v4 14/15]
In reply to Kenji KaneshigeThis is needed because previous two patches make your [PATCH v4 14/15] can not be applied.
---
drivers/pci/hotplug/pci_hotplug_core.c | 6 +++--- include/linux/pci_hotplug.h | 3 --- 2 files changed, 3 insertions(+), 6 deletions(-)
drivers/pci/hotplug/pci_hotplug_core.c +0 -0
@@ -533,7 +533,7 @@ static struct hotplug_slot *get_slot_fro
list_for_each (tmp, &pci_hotplug_slot_list) {
slot = list_entry (tmp, struct hotplug_slot, slot_list);
- if (strcmp(slot->name, name) == 0)
+ if (strcmp(hotplug_slot_name(slot), name) == 0)
return slot;
}
return NULL;
@@ -623,7 +623,7 @@ int pci_hp_deregister(struct hotplug_slo
return -ENODEV;
mutex_lock(&pci_hp_mutex);
- temp = get_slot_from_name(hotplug->name);
+ temp = get_slot_from_name(hotplug_slot_name(hotplug));
if (temp != hotplug) {
mutex_unlock(&pci_hp_mutex);
return -ENODEV;@@ -633,7 +633,7 @@ int pci_hp_deregister(struct hotplug_slo
slot = hotplug->pci_slot; fs_remove_slot(slot);
- dbg("Removed slot %s from the list\n", hotplug->name);
+ dbg("Removed slot %s from the list\n", hotplug_slot_name(hotplug));
hotplug->release(hotplug); slot->hotplug = NULL;
include/linux/pci_hotplug.h +0 -0
@@ -142,8 +142,6 @@ struct hotplug_slot_info {
/**
* struct hotplug_slot - used to register a physical slot with the hotplug pci core
- * @name: the name of the slot being registered. This string must
- * be unique amoung slots registered on this system.
* @ops: pointer to the &struct hotplug_slot_ops to be used for this slot
* @info: pointer to the &struct hotplug_slot_info for the initial values for
* this slot.
@@ -153,7 +151,6 @@ struct hotplug_slot_info {
* needs.
*/
struct hotplug_slot {
- char *name; struct hotplug_slot_ops *ops; struct hotplug_slot_info *info; void (*release) (struct hotplug_slot *slot);
* Kenji Kaneshige <[email protected]>:
Quoted 5 lines
Hi Alex-san,
I have some ideas and made some patches for comments I sent about your [PATCH v4 02/15] and [PATCH v4 03/15]. Please take a look. There are three patches.
Hi Kenji-san,
Thanks for doing this work.
I tested your patches, but found a problem with refcounting in your 02/03, and the slot directories in sysfs remained, even after rmmod of all drivers.
I decided that things are getting too complicated with all these new interfaces, so I got rid of them and updated the pci_create_slot API instead, to take a 'rename' parameter. That way, creating a slot and overriding its name can become an atomic operation.
That should make the race conditions go away, and the code is much easier to understand as well.
Quoted 1 line
- [01/03] Sample patch for [PATCH v4 02/15]
This is a good patch by itself. I think you should submit it to Jesse. I did not need it after reworking to my new design.
Quoted 3 lines
- [02/03] Sample patch for [PATCH v4 03/15] NOTE:This doesn't target the comment about changing exported symbol name.
I had to stare at this patch for a long time to understand it, and finally saw that you were changing the rename logic to detect if we were trying to rename an existing slot.
Unfortunately, it had some problem with the refcounting, and in this scenario:
- pci_slot loaded
- fakephp dup_slots=1 loaded
- pci_slot unloaded
The slots claimed by pci_slot (but _not_ by fakephp) were never released.
By the time I got this far, I was already thinking about a redesign, so I did not try and debug further...
Quoted 3 lines
- [03/03] Sample patch for [PATCH v4 14/15]
This is needed because above two patches make your [PATCH v4 14/15] can not be applied.
Not needed, since I re-designed the approach.
Quoted 3 lines
Note: I made those patches as replacement of your corresponding ones. So those patches are NOT for applying on top your original patches.
Again, thank you very much for all the review and hard work, and sorry for causing so much churn. :-/
I'll be sending out the new patch series shortly.
/ac
Quoted 15 lines · Alex Chiang
* Kenji Kaneshige <[email protected]>:
Quoted 5 lines
Hi Alex-san,
I have some ideas and made some patches for comments I sent about your [PATCH v4 02/15] and [PATCH v4 03/15]. Please take a look. There are three patches.
Hi Kenji-san,
Thanks for doing this work.
I tested your patches, but found a problem with refcounting in your 02/03, and the slot directories in sysfs remained, even after rmmod of all drivers.
Quoted 9 lines
I decided that things are getting too complicated with all these new interfaces, so I got rid of them and updated the
pci_create_slotAPI instead, to take a 'rename' parameter. That way, creating a slot and overriding its name can become an atomic operation.That should make the race conditions go away, and the code is much easier to understand as well.
OK.
I guess one of the thing that will bother us is how to handle the case pci_slot created by pci_create_slot() already has its hotplug callbacks in pci_hp_register(). Current code calls pci_destroy_slot() and return -EBUSY in this case. With the new API which takes 'rename' parameterIn addtion to that, we need to rename the slot as it used to be, in addition.
Quoted 32 lines
Quoted 1 line
- [01/03] Sample patch for [PATCH v4 02/15]
This is a good patch by itself. I think you should submit it to Jesse. I did not need it after reworking to my new design.
Quoted 3 lines
- [02/03] Sample patch for [PATCH v4 03/15] NOTE:This doesn't target the comment about changing exported symbol name.
I had to stare at this patch for a long time to understand it, and finally saw that you were changing the rename logic to detect if we were trying to rename an existing slot.
Unfortunately, it had some problem with the refcounting, and in this scenario:
-
pci_slotloaded
- fakephp dup_slots=1 loaded
-pci_slotunloadedThe slots claimed by
pci_slot(but _not_ by fakephp) were never released.By the time I got this far, I was already thinking about a redesign, so I did not try and debug further...
Quoted 3 lines
- [03/03] Sample patch for [PATCH v4 14/15]
This is needed because above two patches make your [PATCH v4 14/15] can not be applied.Not needed, since I re-designed the approach.
Quoted 9 lines
Quoted 3 lines
Note: I made those patches as replacement of your corresponding ones. So those patches are NOT for applying on top your original patches.
Again, thank you very much for all the review and hard work, and sorry for causing so much churn. :-/
I'll be sending out the new patch series shortly.
No problem.
I'm looking forward to looking at new patches.
Thanks,
Kenji Kaneshige