leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

xen/pcifront: move xenstore config scanning into sub-function

Browse Source 
pcifront_try_connect() and pcifront_attach_devices() share a large
chunk of duplicated code for reading the config information from
Xenstore, which only differs regarding calling pcifront_rescan_root()
or pcifront_scan_root().

Put that code into a new sub-function. It is fine to always call
pcifront_rescan_root() from that common function, as it will fallback
to pcifront_scan_root() if the domain/bus combination isn't known
yet (and pcifront_scan_root() should never be called for an already
known domain/bus combination anyway). In order to avoid duplicate
messages for the fallback case move the check for domain/bus not known
to the beginning of pcifront_rescan_root().

While at it fix the error reporting in case the root-xx node had the
wrong format.

As the return value of pcifront_try_connect() and
pcifront_attach_devices() are not used anywhere make those functions
return void. As an additional bonus this removes the dubious return
of -EFAULT in case of an unexpected driver state.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Juergen Gross 2022-10-06 10:50:28 +02:00
parent 5c13a4a029
commit 2849752f36
1 changed files with 37 additions and 106 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

143
drivers/pci/xen-pcifront.c
View File

@ -521,24 +521,14 @@ static int pcifront_rescan_root(struct pcifront_device *pdev,
int err;
struct pci_bus *b;
#ifndef CONFIG_PCI_DOMAINS
if (domain != 0) {
dev_err(&pdev->xdev->dev,
"PCI Root in non-zero PCI Domain! domain=%d\n", domain);
dev_err(&pdev->xdev->dev,
"Please compile with CONFIG_PCI_DOMAINS\n");
return -EINVAL;
}
#endif
dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
domain, bus);
b = pci_find_bus(domain, bus);
if (!b)
/* If the bus is unknown, create it. */
return pcifront_scan_root(pdev, domain, bus);
dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
domain, bus);
err = pcifront_scan_bus(pdev, domain, bus, b);
/* Claim resources before going "live" with our devices */
@ -819,76 +809,73 @@ out:
return err;
}
static int pcifront_try_connect(struct pcifront_device *pdev)
static void pcifront_connect(struct pcifront_device *pdev)
{
int err = -EFAULT;
int err;
int i, num_roots, len;
char str[64];
unsigned int domain, bus;
/* Only connect once */
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateInitialised)
goto out;
err = pcifront_connect_and_init_dma(pdev);
if (err && err != -EEXIST) {
xenbus_dev_fatal(pdev->xdev, err,
"Error setting up PCI Frontend");
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
err = pcifront_scan_root(pdev, 0, 0);
err = pcifront_rescan_root(pdev, 0, 0);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root 0000:00");
goto out;
return;
}
num_roots = 0;
} else if (err != 1) {
if (err == 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
xenbus_dev_fatal(pdev->xdev, err >= 0 ? -EINVAL : err,
"Error reading number of PCI roots");
goto out;
return;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
if (unlikely(len >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
if (unlikely(len >= (sizeof(str) - 1)))
return;
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
xenbus_dev_fatal(pdev->xdev, err >= 0 ? -EINVAL : err,
"Error reading PCI root %d", i);
goto out;
return;
}
err = pcifront_scan_root(pdev, domain, bus);
err = pcifront_rescan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
goto out;
return;
}
}
err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
xenbus_switch_state(pdev->xdev, XenbusStateConnected);
}
out:
return err;
static void pcifront_try_connect(struct pcifront_device *pdev)
{
int err;
/* Only connect once */
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateInitialised)
return;
err = pcifront_connect_and_init_dma(pdev);
if (err && err != -EEXIST) {
xenbus_dev_fatal(pdev->xdev, err,
"Error setting up PCI Frontend");
return;
}
pcifront_connect(pdev);
}
static int pcifront_try_disconnect(struct pcifront_device *pdev)
@ -914,67 +901,11 @@ out:
return err;
}
static int pcifront_attach_devices(struct pcifront_device *pdev)
static void pcifront_attach_devices(struct pcifront_device *pdev)
{
int err = -EFAULT;
int i, num_roots, len;
unsigned int domain, bus;
char str[64];
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
if (xenbus_read_driver_state(pdev->xdev->nodename) ==
XenbusStateReconfiguring)
goto out;
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
err = pcifront_rescan_root(pdev, 0, 0);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root 0000:00");
goto out;
}
num_roots = 0;
} else if (err != 1) {
if (err == 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading number of PCI roots");
goto out;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
if (unlikely(len >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading PCI root %d", i);
goto out;
}
err = pcifront_rescan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
goto out;
}
}
xenbus_switch_state(pdev->xdev, XenbusStateConnected);
out:
return err;
pcifront_connect(pdev);
}
static int pcifront_detach_devices(struct pcifront_device *pdev)