Commit ba764dd7 authored by Niklas Schnelle's avatar Niklas Schnelle Committed by Vasily Gorbik
Browse files

s390/pci: refactor zpci_create_device() 



Currently zpci_create_device() is only called in clp_add_pci_device()
which allocates the memory for the struct zpci_dev being created. There
is little separation of concerns as only both functions together can
create a zpci_dev and the only CLP specific code in
clp_add_pci_device() is a call to clp_query_pci_fn().

Improve this by removing clp_add_pci_device() and refactor
zpci_create_device() such that it alone creates and initializes the
zpci_dev given the FID and Function Handle. For this we need to make
clp_query_pci_fn() non-static. While at it remove the function handle
parameter since we can just take that from the zpci_dev. Also move
adding to the zpci_list to after the zdev has been fully created which
eliminates a window where a partially initialized zdev can be found by
get_zdev_by_fid().

Acked-by: default avatarPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent bd839171

arch/s390/include/asm/pci.h

+2 −2
Original line number Diff line number Diff line
@@ -201,7 +201,7 @@ extern unsigned int s390_pci_no_rid; 
  Prototypes

----------------------------------------------------------------------------- */

/* Base stuff */

int zpci_create_device(struct zpci_dev *);

int zpci_create_device(u32 fid, u32 fh, enum zpci_state state);

void zpci_remove_device(struct zpci_dev *zdev);

int zpci_enable_device(struct zpci_dev *);

int zpci_disable_device(struct zpci_dev *);
@@ -212,7 +212,7 @@ void zpci_remove_reserved_devices(void); 
/* CLP */

int clp_setup_writeback_mio(void);

int clp_scan_pci_devices(void);

int clp_add_pci_device(u32, u32, int);

int clp_query_pci_fn(struct zpci_dev *zdev);

int clp_enable_fh(struct zpci_dev *, u8);

int clp_disable_fh(struct zpci_dev *);

int clp_get_state(u32 fid, enum zpci_state *state);

arch/s390/pci/pci.c

+41 −16
Original line number Diff line number Diff line
@@ -695,43 +695,68 @@ void zpci_remove_device(struct zpci_dev *zdev) 
	}

}



int zpci_create_device(struct zpci_dev *zdev)

/**

 * zpci_create_device() - Create a new zpci_dev and add it to the zbus

 * @fid: Function ID of the device to be created

 * @fh: Current Function Handle of the device to be created

 * @state: Initial state after creation either Standby or Configured

 *

 * Creates a new zpci device and adds it to its, possibly newly created, zbus

 * as well as zpci_list.

 *

 * Returns: 0 on success, an error value otherwise

 */

int zpci_create_device(u32 fid, u32 fh, enum zpci_state state)

{

	struct zpci_dev *zdev;

	int rc;



	kref_init(&zdev->kref);

	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, state);

	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);

	if (!zdev)

		return -ENOMEM;



	spin_lock(&zpci_list_lock);

	list_add_tail(&zdev->entry, &zpci_list);

	spin_unlock(&zpci_list_lock);

	/* FID and Function Handle are the static/dynamic identifiers */

	zdev->fid = fid;

	zdev->fh = fh;



	rc = zpci_init_iommu(zdev);

	/* Query function properties and update zdev */

	rc = clp_query_pci_fn(zdev);

	if (rc)

		goto out;

		goto error;

	zdev->state =  state;



	kref_init(&zdev->kref);

	mutex_init(&zdev->lock);



	rc = zpci_init_iommu(zdev);

	if (rc)

		goto error;



	if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {

		rc = zpci_enable_device(zdev);

		if (rc)

			goto out_destroy_iommu;

			goto error_destroy_iommu;

	}



	rc = zpci_bus_device_register(zdev, &pci_root_ops);

	if (rc)

		goto out_disable;

		goto error_disable;



	spin_lock(&zpci_list_lock);

	list_add_tail(&zdev->entry, &zpci_list);

	spin_unlock(&zpci_list_lock);



	return 0;



out_disable:

error_disable:

	if (zdev->state == ZPCI_FN_STATE_ONLINE)

		zpci_disable_device(zdev);



out_destroy_iommu:

error_destroy_iommu:

	zpci_destroy_iommu(zdev);

out:

	spin_lock(&zpci_list_lock);

	list_del(&zdev->entry);

	spin_unlock(&zpci_list_lock);

error:

	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);

	kfree(zdev);

	return rc;

}

arch/s390/pci/pci_clp.c

+3 −37
Original line number Diff line number Diff line
@@ -181,7 +181,7 @@ static int clp_store_query_pci_fn(struct zpci_dev *zdev, 
	return 0;

}



static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)

int clp_query_pci_fn(struct zpci_dev *zdev)

{

	struct clp_req_rsp_query_pci *rrb;

	int rc;
@@ -194,7 +194,7 @@ static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh) 
	rrb->request.hdr.len = sizeof(rrb->request);

	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;

	rrb->response.hdr.len = sizeof(rrb->response);

	rrb->request.fh = fh;

	rrb->request.fh = zdev->fh;



	rc = clp_req(rrb, CLP_LPS_PCI);

	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
@@ -212,40 +212,6 @@ static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh) 
	return rc;

}



int clp_add_pci_device(u32 fid, u32 fh, int configured)

{

	struct zpci_dev *zdev;

	int rc = -ENOMEM;



	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);

	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);

	if (!zdev)

		goto error;



	zdev->fh = fh;

	zdev->fid = fid;



	/* Query function properties and update zdev */

	rc = clp_query_pci_fn(zdev, fh);

	if (rc)

		goto error;



	if (configured)

		zdev->state = ZPCI_FN_STATE_CONFIGURED;

	else

		zdev->state = ZPCI_FN_STATE_STANDBY;



	rc = zpci_create_device(zdev);

	if (rc)

		goto error;

	return 0;



error:

	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);

	kfree(zdev);

	return rc;

}



static int clp_refresh_fh(u32 fid);

/*

 * Enable/Disable a given PCI function and update its function handle if
@@ -408,7 +374,7 @@ static void __clp_add(struct clp_fh_list_entry *entry, void *data) 


	zdev = get_zdev_by_fid(entry->fid);

	if (!zdev)

		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);

		zpci_create_device(entry->fid, entry->fh, entry->config_state);

}



int clp_scan_pci_devices(void)

arch/s390/pci/pci_event.c

+2 −2
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf) 
	switch (ccdf->pec) {

	case 0x0301: /* Reserved|Standby -> Configured */

		if (!zdev) {

			ret = clp_add_pci_device(ccdf->fid, ccdf->fh, 1);

			zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_CONFIGURED);

			break;

		}

		/* the configuration request may be stale */
@@ -116,7 +116,7 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf) 
		break;

	case 0x0302: /* Reserved -> Standby */

		if (!zdev) {

			clp_add_pci_device(ccdf->fid, ccdf->fh, 0);

			zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_STANDBY);

			break;

		}

		zdev->fh = ccdf->fh;