diff options
Diffstat (limited to 'include/linux/ntb.h')
-rw-r--r-- | include/linux/ntb.h | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/include/linux/ntb.h b/include/linux/ntb.h index 609e232c00da..c308964777eb 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -70,6 +70,7 @@ struct pci_dev; * @NTB_TOPO_SEC: On secondary side of remote ntb. * @NTB_TOPO_B2B_USD: On primary side of local ntb upstream of remote ntb. * @NTB_TOPO_B2B_DSD: On primary side of local ntb downstream of remote ntb. + * @NTB_TOPO_SWITCH: Connected via a switch which supports ntb. */ enum ntb_topo { NTB_TOPO_NONE = -1, @@ -77,6 +78,7 @@ enum ntb_topo { NTB_TOPO_SEC, NTB_TOPO_B2B_USD, NTB_TOPO_B2B_DSD, + NTB_TOPO_SWITCH, }; static inline int ntb_topo_is_b2b(enum ntb_topo topo) @@ -97,6 +99,7 @@ static inline char *ntb_topo_string(enum ntb_topo topo) case NTB_TOPO_SEC: return "NTB_TOPO_SEC"; case NTB_TOPO_B2B_USD: return "NTB_TOPO_B2B_USD"; case NTB_TOPO_B2B_DSD: return "NTB_TOPO_B2B_DSD"; + case NTB_TOPO_SWITCH: return "NTB_TOPO_SWITCH"; } return "NTB_TOPO_INVALID"; } @@ -730,7 +733,8 @@ static inline int ntb_link_disable(struct ntb_dev *ntb) * Hardware and topology may support a different number of memory windows. * Moreover different peer devices can support different number of memory * windows. Simply speaking this method returns the number of possible inbound - * memory windows to share with specified peer device. + * memory windows to share with specified peer device. Note: this may return + * zero if the link is not up yet. * * Return: the number of memory windows. */ @@ -751,7 +755,7 @@ static inline int ntb_mw_count(struct ntb_dev *ntb, int pidx) * Get the alignments of an inbound memory window with specified index. * NULL may be given for any output parameter if the value is not needed. * The alignment and size parameters may be used for allocation of proper - * shared memory. + * shared memory. Note: this must only be called when the link is up. * * Return: Zero on success, otherwise a negative error number. */ @@ -760,6 +764,9 @@ static inline int ntb_mw_get_align(struct ntb_dev *ntb, int pidx, int widx, resource_size_t *size_align, resource_size_t *size_max) { + if (!(ntb_link_is_up(ntb, NULL, NULL) & (1 << pidx))) + return -ENOTCONN; + return ntb->ops->mw_get_align(ntb, pidx, widx, addr_align, size_align, size_max); } |