apfs/linux-apfs
0
0
Fork 0
mirror of https://github.com/linux-apfs/linux-apfs.git synced 2026-05-01 15:00:59 -07:00
Code Issues Packages Projects Releases Wiki Activity

[PATCH] IB: User MAD ABI changes to support RMPP

Browse Source 
User MAD ABI changes to support RMPP

Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Hal Rosenstock
2005-07-27 11:45:41 -07:00
committed by Linus Torvalds
parent a977049dac
commit 3f75daddb4
2 changed files with 61 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Documentation/infiniband/user_mad.txt
+39 -12
View File
@@ -28,13 +28,37 @@ Creating MAD agents
Receiving MADs
MADs are received using read(). The buffer passed to read() must be
large enough to hold at least one struct ib_user_mad. For example:
MADs are received using read(). The receive side now supports
RMPP. The buffer passed to read() must be at least one
struct ib_user_mad + 256 bytes. For example:
struct ib_user_mad mad;
ret = read(fd, &mad, sizeof mad);
if (ret != sizeof mad)
If the buffer passed is not large enough to hold the received
MAD (RMPP), the errno is set to ENOSPC and the length of the
buffer needed is set in mad.length.
Example for normal MAD (non RMPP) reads:
struct ib_user_mad *mad;
mad = malloc(sizeof *mad + 256);
ret = read(fd, mad, sizeof *mad + 256);
if (ret != sizeof mad + 256) {
perror("read");
free(mad);
}
Example for RMPP reads:
struct ib_user_mad *mad;
mad = malloc(sizeof *mad + 256);
ret = read(fd, mad, sizeof *mad + 256);
if (ret == -ENOSPC)) {
length = mad.length;
free(mad);
mad = malloc(sizeof *mad + length);
ret = read(fd, mad, sizeof *mad + length);
}
if (ret < 0) {
perror("read");
free(mad);
}
In addition to the actual MAD contents, the other struct ib_user_mad
fields will be filled in with information on the received MAD. For
@@ -50,18 +74,21 @@ Sending MADs
MADs are sent using write(). The agent ID for sending should be
filled into the id field of the MAD, the destination LID should be
filled into the lid field, and so on. For example:
filled into the lid field, and so on. The send side does support
RMPP so arbitrary length MAD can be sent. For example:
struct ib_user_mad mad;
struct ib_user_mad *mad;
/* fill in mad.data */
mad = malloc(sizeof *mad + mad_length);
mad.id = my_agent; /* req.id from agent registration */
mad.lid = my_dest; /* in network byte order... */
/* fill in mad->data */
mad->hdr.id = my_agent; /* req.id from agent registration */
mad->hdr.lid = my_dest; /* in network byte order... */
/* etc. */
ret = write(fd, &mad, sizeof mad);
if (ret != sizeof mad)
ret = write(fd, &mad, sizeof *mad + mad_length);
if (ret != sizeof *mad + mad_length)
perror("write");
Setting IsSM Capability Bit