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s390/pci: fix misleading rc in clp_set_pci_fn()

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[ Upstream commit f7addcdd527a6dddfebe20c358b87bdb95624612 ]

Currently clp_set_pci_fn() always returns 0 as long as the CLP request
itself succeeds even if the operation itself returns a response code
other than CLP_RC_OK or CLP_RC_SETPCIFN_ALRDY. This is highly misleading
because calling code assumes that a zero rc means that the operation was
successful.

Fix this by returning the response code or cc on failure with the
exception of the special handling for CLP_RC_SETPCIFN_ALRDY. Also let's
not assume that the returned function handle for CLP_RC_SETPCIFN_ALRDY
is 0, we don't need it anyway.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Niklas Schnelle
2021-07-21 19:58:54 +02:00
committed by Greg Kroah-Hartman
parent 8b471e72b5
commit 0404bf4a66
2 changed files with 20 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
arch/s390/pci/pci.c
View File

@@ -659,9 +659,10 @@ int zpci_enable_device(struct zpci_dev *zdev)
{ {
int rc; int rc;
rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES); if (clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES)) {
if (rc) rc = -EIO;
goto out; goto out;
}
rc = zpci_dma_init_device(zdev); rc = zpci_dma_init_device(zdev);
if (rc) if (rc)
@@ -684,7 +685,7 @@ int zpci_disable_device(struct zpci_dev *zdev)
* The zPCI function may already be disabled by the platform, this is * The zPCI function may already be disabled by the platform, this is
* detected in clp_disable_fh() which becomes a no-op. * detected in clp_disable_fh() which becomes a no-op.
*/ */
return clp_disable_fh(zdev); return clp_disable_fh(zdev) ? -EIO : 0;
} }
EXPORT_SYMBOL_GPL(zpci_disable_device); EXPORT_SYMBOL_GPL(zpci_disable_device);

33
arch/s390/pci/pci_clp.c
View File

@@ -213,15 +213,19 @@ out:
} }
static int clp_refresh_fh(u32 fid); static int clp_refresh_fh(u32 fid);
/* /**
* Enable/Disable a given PCI function and update its function handle if * clp_set_pci_fn() - Execute a command on a PCI function
* necessary * @zdev: Function that will be affected
* @nr_dma_as: DMA address space number
* @command: The command code to execute
*
* Returns: 0 on success, < 0 for Linux errors (e.g. -ENOMEM), and
* > 0 for non-success platform responses
*/ */
static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command) static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
{ {
struct clp_req_rsp_set_pci *rrb; struct clp_req_rsp_set_pci *rrb;
int rc, retries = 100; int rc, retries = 100;
u32 fid = zdev->fid;
rrb = clp_alloc_block(GFP_KERNEL); rrb = clp_alloc_block(GFP_KERNEL);
if (!rrb) if (!rrb)
@@ -245,17 +249,16 @@ static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
} }
} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY); } while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
zpci_err("Set PCI FN:\n");
zpci_err_clp(rrb->response.hdr.rsp, rc);
}
if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) { if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
zdev->fh = rrb->response.fh; zdev->fh = rrb->response.fh;
} else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY && } else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY) {
rrb->response.fh == 0) {
/* Function is already in desired state - update handle */ /* Function is already in desired state - update handle */
rc = clp_refresh_fh(fid); rc = clp_refresh_fh(zdev->fid);
} else {
zpci_err("Set PCI FN:\n");
zpci_err_clp(rrb->response.hdr.rsp, rc);
if (!rc)
rc = rrb->response.hdr.rsp;
} }
clp_free_block(rrb); clp_free_block(rrb);
return rc; return rc;
@@ -301,17 +304,13 @@ int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN); rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc); zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
if (rc) if (!rc && zpci_use_mio(zdev)) {
goto out;
if (zpci_use_mio(zdev)) {
rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO); rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO);
zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n", zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
zdev->fid, zdev->fh, rc); zdev->fid, zdev->fh, rc);
if (rc) if (rc)
clp_disable_fh(zdev); clp_disable_fh(zdev);
} }
out:
return rc; return rc;
} }