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s390/pci: refactor zpci_create_device()

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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: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Niklas Schnelle 2020-07-22 16:53:54 +02:00 committed by Vasily Gorbik
parent bd83917155
commit ba764dd703
4 changed files with 55 additions and 64 deletions
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4
arch/s390/include/asm/pci.h
View File

@ -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);

71
arch/s390/pci/pci.c
View File

@ -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;
zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, state);
zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
if (!zdev)
return -ENOMEM;
/* FID and Function Handle are the static/dynamic identifiers */
zdev->fid = fid;
zdev->fh = fh;
/* Query function properties and update zdev */
rc = clp_query_pci_fn(zdev);
if (rc)
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 error_destroy_iommu;
}
rc = zpci_bus_device_register(zdev, &pci_root_ops);
if (rc)
goto error_disable;
spin_lock(&zpci_list_lock);
list_add_tail(&zdev->entry, &zpci_list);
spin_unlock(&zpci_list_lock);
rc = zpci_init_iommu(zdev);
if (rc)
goto out;
mutex_init(&zdev->lock);
if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {
rc = zpci_enable_device(zdev);
if (rc)
goto out_destroy_iommu;
}
rc = zpci_bus_device_register(zdev, &pci_root_ops);
if (rc)
goto out_disable;
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;
}

40
arch/s390/pci/pci_clp.c
View File

@ -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 @@ out:
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)

4
arch/s390/pci/pci_event.c
View File

@ -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;