/* * net/9p/util.c * * This file contains some helper functions * * Copyright (C) 2007 by Latchesar Ionkov * Copyright (C) 2004 by Eric Van Hensbergen * Copyright (C) 2002 by Ron Minnich * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to: * Free Software Foundation * 51 Franklin Street, Fifth Floor * Boston, MA 02111-1301 USA * */ #include #include #include #include #include #include #include #include /** * struct p9_idpool - per-connection accounting for tag idpool * @lock: protects the pool * @pool: idr to allocate tag id from * */ struct p9_idpool { spinlock_t lock; struct idr pool; }; /** * p9_idpool_create - create a new per-connection id pool * */ struct p9_idpool *p9_idpool_create(void) { struct p9_idpool *p; p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL); if (!p) return ERR_PTR(-ENOMEM); spin_lock_init(&p->lock); idr_init(&p->pool); return p; } EXPORT_SYMBOL(p9_idpool_create); /** * p9_idpool_destroy - create a new per-connection id pool * @p: idpool to destroy */ void p9_idpool_destroy(struct p9_idpool *p) { idr_destroy(&p->pool); kfree(p); } EXPORT_SYMBOL(p9_idpool_destroy); /** * p9_idpool_get - allocate numeric id from pool * @p: pool to allocate from * * Bugs: This seems to be an awful generic function, should it be in idr.c with * the lock included in struct idr? */ int p9_idpool_get(struct p9_idpool *p) { int i; unsigned long flags; idr_preload(GFP_NOFS); spin_lock_irqsave(&p->lock, flags); /* no need to store exactly p, we just need something non-null */ i = idr_alloc(&p->pool, p, 0, 0, GFP_NOWAIT); spin_unlock_irqrestore(&p->lock, flags); idr_preload_end(); if (i < 0) return -1; p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", i, p); return i; } EXPORT_SYMBOL(p9_idpool_get); /** * p9_idpool_put - release numeric id from pool * @id: numeric id which is being released * @p: pool to release id into * * Bugs: This seems to be an awful generic function, should it be in idr.c with * the lock included in struct idr? */ void p9_idpool_put(int id, struct p9_idpool *p) { unsigned long flags; p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", id, p); spin_lock_irqsave(&p->lock, flags); idr_remove(&p->pool, id); spin_unlock_irqrestore(&p->lock, flags); } EXPORT_SYMBOL(p9_idpool_put); /** * p9_idpool_check - check if the specified id is available * @id: id to check * @p: pool to check */ int p9_idpool_check(int id, struct p9_idpool *p) { return idr_find(&p->pool, id) != NULL; } EXPORT_SYMBOL(p9_idpool_check); 2f'/>
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authorSriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>2017-01-09 16:00:44 +0530
committerJ. Bruce Fields <bfields@redhat.com>2017-01-12 16:14:47 -0500
commitce1ca7d2d140a1f4aaffd297ac487f246963dd2f (patch)
tree5aeab5e0cb6ef404c894a18251588278b9432a2c /include/uapi/drm
parent546125d1614264d26080817d0c8cddb9b25081fa (diff)
svcrdma: avoid duplicate dma unmapping during error recovery
In rdma_read_chunk_frmr() when ib_post_send() fails, the error code path invokes ib_dma_unmap_sg() to unmap the sg list. It then invokes svc_rdma_put_frmr() which in turn tries to unmap the same sg list through ib_dma_unmap_sg() again. This second unmap is invalid and could lead to problems when the iova being unmapped is subsequently reused. Remove the call to unmap in rdma_read_chunk_frmr() and let svc_rdma_put_frmr() handle it. Fixes: 412a15c0fe53 ("svcrdma: Port to new memory registration API") Cc: stable@vger.kernel.org Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'include/uapi/drm')