diff options
| author | Logan Gunthorpe | 2017-08-03 12:19:45 -0600 |
|---|---|---|
| committer | Jon Mason | 2017-11-18 20:37:11 -0500 |
| commit | fa5ab66e36de56f7e40dad57780d53e059dced86 (patch) | |
| tree | 7239deea35b4e92edd76ce65f7970b3ca077f248 /include/linux | |
| parent | 980c41c86b37b6086ad758566b437cb1a469b4bc (diff) | |
NTB: Add check and comment for link up to mw_count() and mw_get_align()
Adds a comment and a check to ntb_mw_get_align() so that it always fails
if the function is called before the link is up.
Also adds a comment to ntb_mw_count() to note that it may return 0 if
it is called before the link is up.
This is to prevent accidental mis-use in clients that are testing
on hardware that this doesn't matter for.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/ntb.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/include/linux/ntb.h b/include/linux/ntb.h index 609e232c00da..47f2966cfd7f 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -730,7 +730,8 @@ 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 +752,7 @@ 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 +761,9 @@ 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); } |