RDMA/siw: Remove unused siw_mem_add

siw_mem_add() was added in 2019 by commit 2251334 ("rdma/siw:
application buffer management") but has remained unused.

Remove it.

Link: https://patch.msgid.link/r/20250505210226.88994-1-linux@treblig.org
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Acked-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Author: Dr. David Alan Gilbert

drivers/infiniband/sw/siw/siw_mem.c

@@ -17,30 +17,6 @@
 /* Stag lookup is based on its index part only (24 bits). */
 #define SIW_STAG_MAX_INDEX	0x00ffffff
 
-/*
- * The code avoids special Stag of zero and tries to randomize
- * STag values between 1 and SIW_STAG_MAX_INDEX.
- */
-int siw_mem_add(struct siw_device *sdev, struct siw_mem *m)
-{
-	struct xa_limit limit = XA_LIMIT(1, SIW_STAG_MAX_INDEX);
-	u32 id, next;
-
-	get_random_bytes(&next, 4);
-	next &= SIW_STAG_MAX_INDEX;
-
-	if (xa_alloc_cyclic(&sdev->mem_xa, &id, m, limit, &next,
-	    GFP_KERNEL) < 0)
-		return -ENOMEM;
-
-	/* Set the STag index part */
-	m->stag = id << 8;
-
-	siw_dbg_mem(m, "new MEM object\n");
-
-	return 0;
-}
-
 /*
  * siw_mem_id2obj()
  *

drivers/infiniband/sw/siw/siw_mem.h

@@ -12,7 +12,6 @@ void siw_umem_release(struct siw_umem *umem);
 struct siw_pbl *siw_pbl_alloc(u32 num_buf);
 dma_addr_t siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx);
 struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index);
-int siw_mem_add(struct siw_device *sdev, struct siw_mem *m);
 int siw_invalidate_stag(struct ib_pd *pd, u32 stag);
 int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
 		  enum ib_access_flags perms, int len);