s390/pci: improve error handling during fmb (de)registration

Cleanup in zpci_fmb_enable_device when fmb registration fails. Also
don't free the fmb when deregistration fails in zpci_fmb_disable_device
but handle error situations when a function was hot-unplugged.

Also remove the mod_pci helper since it is no longer used.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 4f541f54470f2bc917da411868b2880a42591cf0..6a44a68efb81e25150e30923fcddb71149d2e8c2 100644 (file)
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -136,27 +136,6 @@ static int zpci_clear_airq(struct zpci_dev *zdev)
        return cc ? -EIO : 0;
 }
 
-struct mod_pci_args {
-       u64 base;
-       u64 limit;
-       u64 iota;
-       u64 fmb_addr;
-};
-
-static int mod_pci(struct zpci_dev *zdev, int fn, u8 dmaas, struct mod_pci_args *args)
-{
-       u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, fn);
-       struct zpci_fib fib = {0};
-       u8 status;
-
-       fib.pba = args->base;
-       fib.pal = args->limit;
-       fib.iota = args->iota;
-       fib.fmb_addr = args->fmb_addr;
-
-       return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
-}
-
 /* Modify PCI: Register I/O address translation parameters */
 int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
                       u64 base, u64 limit, u64 iota)
@@ -188,7 +167,9 @@ int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas)
 /* Modify PCI: Set PCI function measurement parameters */
 int zpci_fmb_enable_device(struct zpci_dev *zdev)
 {
-       struct mod_pci_args args = { 0, 0, 0, 0 };
+       u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
+       struct zpci_fib fib = {0};
+       u8 cc, status;
 
        if (zdev->fmb || sizeof(*zdev->fmb) < zdev->fmb_length)
                return -EINVAL;
@@ -203,25 +184,35 @@ int zpci_fmb_enable_device(struct zpci_dev *zdev)
        atomic64_set(&zdev->mapped_pages, 0);
        atomic64_set(&zdev->unmapped_pages, 0);
 
-       args.fmb_addr = virt_to_phys(zdev->fmb);
-       return mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
+       fib.fmb_addr = virt_to_phys(zdev->fmb);
+       cc = zpci_mod_fc(req, &fib, &status);
+       if (cc) {
+               kmem_cache_free(zdev_fmb_cache, zdev->fmb);
+               zdev->fmb = NULL;
+       }
+       return cc ? -EIO : 0;
 }
 
 /* Modify PCI: Disable PCI function measurement */
 int zpci_fmb_disable_device(struct zpci_dev *zdev)
 {
-       struct mod_pci_args args = { 0, 0, 0, 0 };
-       int rc;
+       u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
+       struct zpci_fib fib = {0};
+       u8 cc, status;
 
        if (!zdev->fmb)
                return -EINVAL;
 
        /* Function measurement is disabled if fmb address is zero */
-       rc = mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
+       cc = zpci_mod_fc(req, &fib, &status);
+       if (cc == 3) /* Function already gone. */
+               cc = 0;
 
-       kmem_cache_free(zdev_fmb_cache, zdev->fmb);
-       zdev->fmb = NULL;
-       return rc;
+       if (!cc) {
+               kmem_cache_free(zdev_fmb_cache, zdev->fmb);
+               zdev->fmb = NULL;
+       }
+       return cc ? -EIO : 0;
 }
 
 static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)