/* * Copyright (c) 2000,2005 Silicon Graphics, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would 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 the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef __XFS_TRANS_SPACE_H__ #define __XFS_TRANS_SPACE_H__ /* * Components of space reservations. */ #define XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) \ (((mp)->m_rmap_mxr[0]) - ((mp)->m_rmap_mnr[0])) #define XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) \ (((mp)->m_alloc_mxr[0]) - ((mp)->m_alloc_mnr[0])) #define XFS_EXTENTADD_SPACE_RES(mp,w) (XFS_BM_MAXLEVELS(mp,w) - 1) #define XFS_NEXTENTADD_SPACE_RES(mp,b,w)\ (((b + XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) - 1) / \ XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp)) * \ XFS_EXTENTADD_SPACE_RES(mp,w)) #define XFS_SWAP_RMAP_SPACE_RES(mp,b,w)\ (((b + XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) - 1) / \ XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp)) * \ XFS_EXTENTADD_SPACE_RES(mp,w) + \ ((b + XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) - 1) / \ XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp)) * \ (mp)->m_rmap_maxlevels) #define XFS_DAENTER_1B(mp,w) \ ((w) == XFS_DATA_FORK ? (mp)->m_dir_geo->fsbcount : 1) #define XFS_DAENTER_DBS(mp,w) \ (XFS_DA_NODE_MAXDEPTH + (((w) == XFS_DATA_FORK) ? 2 : 0)) #define XFS_DAENTER_BLOCKS(mp,w) \ (XFS_DAENTER_1B(mp,w) * XFS_DAENTER_DBS(mp,w)) #define XFS_DAENTER_BMAP1B(mp,w) \ XFS_NEXTENTADD_SPACE_RES(mp, XFS_DAENTER_1B(mp, w), w) #define XFS_DAENTER_BMAPS(mp,w) \ (XFS_DAENTER_DBS(mp,w) * XFS_DAENTER_BMAP1B(mp,w)) #define XFS_DAENTER_SPACE_RES(mp,w) \ (XFS_DAENTER_BLOCKS(mp,w) + XFS_DAENTER_BMAPS(mp,w)) #define XFS_DAREMOVE_SPACE_RES(mp,w) XFS_DAENTER_BMAPS(mp,w) #define XFS_DIRENTER_MAX_SPLIT(mp,nl) 1 #define XFS_DIRENTER_SPACE_RES(mp,nl) \ (XFS_DAENTER_SPACE_RES(mp, XFS_DATA_FORK) * \ XFS_DIRENTER_MAX_SPLIT(mp,nl)) #define XFS_DIRREMOVE_SPACE_RES(mp) \ XFS_DAREMOVE_SPACE_RES(mp, XFS_DATA_FORK) #define XFS_IALLOC_SPACE_RES(mp) \ ((mp)->m_ialloc_blks + \ (xfs_sb_version_hasfinobt(&mp->m_sb) ? 2 : 1 * \ ((mp)->m_in_maxlevels - 1))) /* * Space reservation values for various transactions. */ #define XFS_ADDAFORK_SPACE_RES(mp) \ ((mp)->m_dir_geo->fsbcount + XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK)) #define XFS_ATTRRM_SPACE_RES(mp) \ XFS_DAREMOVE_SPACE_RES(mp, XFS_ATTR_FORK) /* This macro is not used - see inline code in xfs_attr_set */ #define XFS_ATTRSET_SPACE_RES(mp, v) \ (XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK) + XFS_B_TO_FSB(mp, v)) #define XFS_CREATE_SPACE_RES(mp,nl) \ (XFS_IALLOC_SPACE_RES(mp) + XFS_DIRENTER_SPACE_RES(mp,nl)) #define XFS_DIOSTRAT_SPACE_RES(mp, v) \ (XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK) + (v)) #define XFS_GROWFS_SPACE_RES(mp) \ (2 * (mp)->m_ag_maxlevels) #define XFS_GROWFSRT_SPACE_RES(mp,b) \ ((b) + XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK)) #define XFS_LINK_SPACE_RES(mp,nl) \ XFS_DIRENTER_SPACE_RES(mp,nl) #define XFS_MKDIR_SPACE_RES(mp,nl) \ (XFS_IALLOC_SPACE_RES(mp) + XFS_DIRENTER_SPACE_RES(mp,nl)) #define XFS_QM_DQALLOC_SPACE_RES(mp) \ (XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK) + \ XFS_DQUOT_CLUSTER_SIZE_FSB) #define XFS_QM_QINOCREATE_SPACE_RES(mp) \ XFS_IALLOC_SPACE_RES(mp) #define XFS_REMOVE_SPACE_RES(mp) \ XFS_DIRREMOVE_SPACE_RES(mp) #define XFS_RENAME_SPACE_RES(mp,nl) \ (XFS_DIRREMOVE_SPACE_RES(mp) + XFS_DIRENTER_SPACE_RES(mp,nl)) #define XFS_SYMLINK_SPACE_RES(mp,nl,b) \ (XFS_IALLOC_SPACE_RES(mp) + XFS_DIRENTER_SPACE_RES(mp,nl) + (b)) #define XFS_IFREE_SPACE_RES(mp) \ (xfs_sb_version_hasfinobt(&mp->m_sb) ? (mp)->m_in_maxlevels : 0) #endif /* __XFS_TRANS_SPACE_H__ */ /select>space:mode:
authorDouglas Miller <dougmill@linux.vnet.ibm.com>2017-01-28 06:42:20 -0600
committerTejun Heo <tj@kernel.org>2017-01-28 07:49:42 -0500
commit966d2b04e070bc040319aaebfec09e0144dc3341 (patch)
tree4b96156e3d1dd4dfd6039b7c219c9dc4616da52d /include/uapi/xen/evtchn.h
parent1b1bc42c1692e9b62756323c675a44cb1a1f9dbd (diff)
percpu-refcount: fix reference leak during percpu-atomic transition
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'include/uapi/xen/evtchn.h')