/* * Copyright (c) 2000-2006 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 */ #include #include "xfs.h" #include "xfs_fs.h" #include "xfs_format.h" #include "xfs_log.h" #include "xfs_inum.h" #include "xfs_trans.h" #include "xfs_trans_space.h" #include "xfs_trans_priv.h" #include "xfs_sb.h" #include "xfs_ag.h" #include "xfs_mount.h" #include "xfs_da_btree.h" #include "xfs_dir2_format.h" #include "xfs_dir2.h" #include "xfs_bmap_btree.h" #include "xfs_alloc_btree.h" #include "xfs_ialloc_btree.h" #include "xfs_attr_sf.h" #include "xfs_attr.h" #include "xfs_dinode.h" #include "xfs_inode.h" #include "xfs_buf_item.h" #include "xfs_inode_item.h" #include "xfs_btree.h" #include "xfs_alloc.h" #include "xfs_ialloc.h" #include "xfs_bmap.h" #include "xfs_bmap_util.h" #include "xfs_error.h" #include "xfs_quota.h" #include "xfs_filestream.h" #include "xfs_cksum.h" #include "xfs_trace.h" #include "xfs_icache.h" #include "xfs_symlink.h" kmem_zone_t *xfs_inode_zone; /* * Used in xfs_itruncate_extents(). This is the maximum number of extents * freed from a file in a single transaction. */ #define XFS_ITRUNC_MAX_EXTENTS 2 STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *); /* * helper function to extract extent size hint from inode */ xfs_extlen_t xfs_get_extsz_hint( struct xfs_inode *ip) { if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize) return ip->i_d.di_extsize; if (XFS_IS_REALTIME_INODE(ip)) return ip->i_mount->m_sb.sb_rextsize; return 0; } /* * This is a wrapper routine around the xfs_ilock() routine used to centralize * some grungy code. It is used in places that wish to lock the inode solely * for reading the extents. The reason these places can't just call * xfs_ilock(SHARED) is that the inode lock also guards to bringing in of the * extents from disk for a file in b-tree format. If the inode is in b-tree * format, then we need to lock the inode exclusively until the extents are read * in. Locking it exclusively all the time would limit our parallelism * unnecessarily, though. What we do instead is check to see if the extents * have been read in yet, and only lock the inode exclusively if they have not. * * The function returns a value which should be given to the corresponding * xfs_iunlock_map_shared(). This value is the mode in which the lock was * actually taken. */ uint xfs_ilock_map_shared( xfs_inode_t *ip) { uint lock_mode; if ((ip->i_d.di_format == XFS_DINODE_FMT_BTREE) && ((ip->i_df.if_flags & XFS_IFEXTENTS) == 0)) { lock_mode = XFS_ILOCK_EXCL; } else { lock_mode = XFS_ILOCK_SHARED; } xfs_ilock(ip, lock_mode); return lock_mode; } /* * This is simply the unlock routine to go with xfs_ilock_map_shared(). * All it does is call xfs_iunlock() with the given lock_mode. */ void xfs_iunlock_map_shared( xfs_inode_t *ip, unsigned int lock_mode) { xfs_iunlock(ip, lock_mode); } /* * The xfs inode contains 2 locks: a multi-reader lock called the * i_iolock and a multi-reader lock called the i_lock. This routine * allows either or both of the locks to be obtained. * * The 2 locks should always be ordered so that the IO lock is * obtained first in order to prevent deadlock. * * ip -- the inode being locked * lock_flags -- this parameter indicates the inode's locks * to be locked. It can be: * XFS_IOLOCK_SHARED, * XFS_IOLOCK_EXCL, * XFS_ILOCK_SHARED, * XFS_ILOCK_EXCL, * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED, * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL, * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED, * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL */ void xfs_ilock( xfs_inode_t *ip, uint lock_flags) { trace_xfs_ilock(ip, lock_flags, _RET_IP_); /* * You can't set both SHARED and EXCL for the same lock, * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, * and XFS_ILOCK_EXCL are valid values to set in lock_flags. */ ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); else if (lock_flags & XFS_IOLOCK_SHARED) mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); if (lock_flags & XFS_ILOCK_EXCL) mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); else if (lock_flags & XFS_ILOCK_SHARED) mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); } /* * This is just like xfs_ilock(), except that the caller * is guaranteed not to sleep. It returns 1 if it gets * the requested locks and 0 otherwise. If the IO lock is * obtained but the inode lock cannot be, then the IO lock * is dropped before returning. * * ip -- the inode being locked * lock_flags -- this parameter indicates the inode's locks to be * to be locked. See the comment for xfs_ilock() for a list * of valid values. */ int xfs_ilock_nowait( xfs_inode_t *ip, uint lock_flags) { trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_); /* * You can't set both SHARED and EXCL for the same lock, * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, * and XFS_ILOCK_EXCL are valid values to set in lock_flags. */ ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) { if (!mrtryupdate(&ip->i_iolock)) goto out; } else if (lock_flags & XFS_IOLOCK_SHARED) { if (!mrtryaccess(&ip->i_iolock)) goto out; } if (lock_flags & XFS_ILOCK_EXCL) { if (!mrtryupdate(&ip->i_lock)) goto out_undo_iolock; } else if (lock_flags & XFS_ILOCK_SHARED) { if (!mrtryaccess(&ip->i_lock)) goto out_undo_iolock; } return 1; out_undo_iolock: if (lock_flags & XFS_IOLOCK_EXCL) mrunlock_excl(&ip->i_iolock); else if (lock_flags & XFS_IOLOCK_SHARED) mrunlock_shared(&ip->i_iolock); out: return 0; } /* * xfs_iunlock() is used to drop the inode locks acquired with * xfs_ilock() and xfs_ilock_nowait(). The caller must pass * in the flags given to xfs_ilock() or xfs_ilock_nowait() so * that we know which locks to drop. * * ip -- the inode being unlocked * lock_flags -- this parameter indicates the inode's locks to be * to be unlocked. See the comment for xfs_ilock() for a list * of valid values for this parameter. * */ void xfs_iunlock( xfs_inode_t *ip, uint lock_flags) { /* * You can't set both SHARED and EXCL for the same lock, * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, * and XFS_ILOCK_EXCL are valid values to set in lock_flags. */ ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); ASSERT(lock_flags != 0); if (lock_flags & XFS_IOLOCK_EXCL) mrunlock_excl(&ip->i_iolock); else if (lock_flags & XFS_IOLOCK_SHARED) mrunlock_shared(&ip->i_iolock); if (lock_flags & XFS_ILOCK_EXCL) mrunlock_excl(&ip->i_lock); else if (lock_flags & XFS_ILOCK_SHARED) mrunlock_shared(&ip->i_lock); trace_xfs_iunlock(ip, lock_flags, _RET_IP_); } /* * give up write locks. the i/o lock cannot be held nested * if it is being demoted. */ void xfs_ilock_demote( xfs_inode_t *ip, uint lock_flags) { ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); if (lock_flags & XFS_ILOCK_EXCL) mrdemote(&ip->i_lock); if (lock_flags & XFS_IOLOCK_EXCL) mrdemote(&ip->i_iolock); trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_); } #if defined(DEBUG) || defined(XFS_WARN) int xfs_isilocked( xfs_inode_t *ip, uint lock_flags) { if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) { if (!(lock_flags & XFS_ILOCK_SHARED)) return !!ip->i_lock.mr_writer; return rwsem_is_locked(&ip->i_lock.mr_lock); } if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) { if (!(lock_flags & XFS_IOLOCK_SHARED)) return !!ip->i_iolock.mr_writer; return rwsem_is_locked(&ip->i_iolock.mr_lock); } ASSERT(0); return 0; } #endif #ifdef DEBUG int xfs_locked_n; int xfs_small_retries; int xfs_middle_retries; int xfs_lots_retries; int xfs_lock_delays; #endif /* * Bump the subclass so xfs_lock_inodes() acquires each lock with * a different value */ static inline int xfs_lock_inumorder(int lock_mode, int subclass) { if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT; if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT; return lock_mode; } /* * The following routine will lock n inodes in exclusive mode. * We assume the caller calls us with the inodes in i_ino order. * * We need to detect deadlock where an inode that we lock * is in the AIL and we start waiting for another inode that is locked * by a thread in a long running transaction (such as truncate). This can * result in deadlock since the long running trans might need to wait * for the inode we just locked in order to push the tail and free space * in the log. */ void xfs_lock_inodes( xfs_inode_t **ips, int inodes, uint lock_mode) { int attempts = 0, i, j, try_lock; xfs_log_item_t *lp; ASSERT(ips && (inodes >= 2)); /* we need at least two */ try_lock = 0; i = 0; again: for (; i < inodes; i++) { ASSERT(ips[i]); if (i && (ips[i] == ips[i-1])) /* Already locked */ continue; /* * If try_lock is not set yet, make sure all locked inodes * are not in the AIL. * If any are, set try_lock to be used later. */ if (!try_lock) { for (j = (i - 1); j >= 0 && !try_lock; j--) { lp = (xfs_log_item_t *)ips[j]->i_itemp; if (lp && (lp->li_flags & XFS_LI_IN_AIL)) { try_lock++; } } } /* * If any of the previous locks we have locked is in the AIL, * we must TRY to get the second and subsequent locks. If * we can't get any, we must release all we have * and try again. */ if (try_lock) { /* try_lock must be 0 if i is 0. */ /* * try_lock means we have an inode locked * that is in the AIL. */ ASSERT(i != 0); if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) { attempts++; /* * Unlock all previous guys and try again. * xfs_iunlock will try to push the tail * if the inode is in the AIL. */ for(j = i - 1; j >= 0; j--) { /* * Check to see if we've already * unlocked this one. * Not the first one going back, * and the inode ptr is the same. */ if ((j != (i - 1)) && ips[j] == ips[j+1]) continue; xfs_iunlock(ips[j], lock_mode); } if ((attempts % 5) == 0) { delay(1); /* Don't just spin the CPU */ #ifdef DEBUG xfs_lock_delays++; #endif } i = 0; try_lock = 0; goto again; } } else { xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i)); } } #ifdef DEBUG if (attempts) { if (attempts < 5) xfs_small_retries++; else if (attempts < 100) xfs_middle_retries++; else xfs_lots_retries++; } else { xfs_locked_n++; } #endif } /* * xfs_lock_two_inodes() can only be used to lock one type of lock * at a time - the iolock or the ilock, but not both at once. If * we lock both at once, lockdep will report false positives saying * we have violated locking orders. */ void xfs_lock_two_inodes( xfs_inode_t *ip0, xfs_inode_t *ip1, uint lock_mode) { xfs_inode_t *temp; int attempts = 0; xfs_log_item_t *lp; if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0); ASSERT(ip0->i_ino != ip1->i_ino); if (ip0->i_ino > ip1->i_ino) { temp = ip0; ip0 = ip1; ip1 = temp; } again: xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0)); /* * If the first lock we have locked is in the AIL, we must TRY to get * the second lock. If we can't get it, we must release the first one * and try again. */ lp = (xfs_log_item_t *)ip0->i_itemp; if (lp && (lp->li_flags & XFS_LI_IN_AIL)) { if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) { xfs_iunlock(ip0, lock_mode); if ((++attempts % 5) == 0) delay(1); /* Don't just spin the CPU */ goto again; } } else { xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1)); } } void __xfs_iflock( struct xfs_inode *ip) { wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT); DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT); do { prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE); if (xfs_isiflocked(ip)) io_schedule(); } while (!xfs_iflock_nowait(ip)); finish_wait(wq, &wait.wait); } STATIC uint _xfs_dic2xflags( __uint16_t di_flags) { uint flags = 0; if (di_flags & XFS_DIFLAG_ANY) { if (di_flags & XFS_DIFLAG_REALTIME) flags |= XFS_XFLAG_REALTIME; if (di_flags & XFS_DIFLAG_PREALLOC) flags |= XFS_XFLAG_PREALLOC; if (di_flags & XFS_DIFLAG_IMMUTABLE) flags |= XFS_XFLAG_IMMUTABLE; if (di_flags & XFS_DIFLAG_APPEND) flags |= XFS_XFLAG_APPEND; if (di_flags & XFS_DIFLAG_SYNC) flags |= XFS_XFLAG_SYNC; if (di_flags & XFS_DIFLAG_NOATIME) flags |= XFS_XFLAG_NOATIME; if (di_flags & XFS_DIFLAG_NODUMP) flags |= XFS_XFLAG_NODUMP; if (di_flags & XFS_DIFLAG_RTINHERIT) flags |= XFS_XFLAG_RTINHERIT; if (di_flags & XFS_DIFLAG_PROJINHERIT) flags |= XFS_XFLAG_PROJINHERIT; if (di_flags & XFS_DIFLAG_NOSYMLINKS) flags |= XFS_XFLAG_NOSYMLINKS; if (di_flags & XFS_DIFLAG_EXTSIZE) flags |= XFS_XFLAG_EXTSIZE; if (di_flags & XFS_DIFLAG_EXTSZINHERIT) flags |= XFS_XFLAG_EXTSZINHERIT; if (di_flags & XFS_DIFLAG_NODEFRAG) flags |= XFS_XFLAG_NODEFRAG; if (di_flags & XFS_DIFLAG_FILESTREAM) flags |= XFS_XFLAG_FILESTREAM; } return flags; } uint xfs_ip2xflags( xfs_inode_t *ip) { xfs_icdinode_t *dic = &ip->i_d; return _xfs_dic2xflags(dic->di_flags) | (XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0); } uint xfs_dic2xflags( xfs_dinode_t *dip) { return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) | (XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0); } /* * Lookups up an inode from "name". If ci_name is not NULL, then a CI match * is allowed, otherwise it has to be an exact match. If a CI match is found, * ci_name->name will point to a the actual name (caller must free) or * will be set to NULL if an exact match is found. */ int xfs_lookup( xfs_inode_t *dp, struct xfs_name *name, xfs_inode_t **ipp, struct xfs_name *ci_name) { xfs_ino_t inum; int error; uint lock_mode; trace_xfs_lookup(dp, name); if (XFS_FORCED_SHUTDOWN(dp->i_mount)) return XFS_ERROR(EIO); lock_mode = xfs_ilock_map_shared(dp); error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name); xfs_iunlock_map_shared(dp, lock_mode); if (error) goto out; error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp); if (error) goto out_free_name; return 0; out_free_name: if (ci_name) kmem_free(ci_name->name); out: *ipp = NULL; return error; } /* * Allocate an inode on disk and return a copy of its in-core version. * The in-core inode is locked exclusively. Set mode, nlink, and rdev * appropriately within the inode. The uid and gid for the inode are * set according to the contents of the given cred structure. * * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc() * has a free inode available, call xfs_iget() to obtain the in-core * version of the allocated inode. Finally, fill in the inode and * log its initial contents. In this case, ialloc_context would be * set to NULL. * * If xfs_dialloc() does not have an available inode, it will replenish * its supply by doing an allocation. Since we can only do one * allocation within a transaction without deadlocks, we must commit * the current transaction before returning the inode itself. * In this case, therefore, we will set ialloc_context and return. * The caller should then commit the current transaction, start a new * transaction, and call xfs_ialloc() again to actually get the inode. * * To ensure that some other process does not grab the inode that * was allocated during the first call to xfs_ialloc(), this routine * also returns the [locked] bp pointing to the head of the freelist * as ialloc_context. The caller should hold this buffer across * the commit and pass it back into this routine on the second call. * * If we are allocating quota inodes, we do not have a parent inode * to attach to or associate with (i.e. pip == NULL) because they * are not linked into the directory structure - they are attached * directly to the superblock - and so have no parent. */ int xfs_ialloc( xfs_trans_t *tp, xfs_inode_t *pip, umode_t mode, xfs_nlink_t nlink, xfs_dev_t rdev, prid_t prid, int okalloc, xfs_buf_t **ialloc_context, xfs_inode_t **ipp) { struct xfs_mount *mp = tp->t_mountp; xfs_ino_t ino; xfs_inode_t *ip; uint flags; int error; timespec_t tv; int filestreams = 0; /* * Call the space management code to pick * the on-disk inode to be allocated. */ error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc, ialloc_context, &ino); if (error) return error; if (*ialloc_context || ino == NULLFSINO) { *ipp = NULL; return 0; } ASSERT(*ialloc_context == NULL); /* * Get the in-core inode with the lock held exclusively. * This is because we're setting fields here we need * to prevent others from looking at until we're done. */ error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip); if (error) return error; ASSERT(ip != NULL); ip->i_d.di_mode = mode; ip->i_d.di_onlink = 0; ip->i_d.di_nlink = nlink; ASSERT(ip->i_d.di_nlink == nlink); ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid()); ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid()); xfs_set_projid(ip, prid); memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad)); /* * If the superblock version is up to where we support new format * inodes and this is currently an old format inode, then change * the inode version number now. This way we only do the conversion * here rather than here and in the flush/logging code. */ if (xfs_sb_version_hasnlink(&mp->m_sb) && ip->i_d.di_version == 1) { ip->i_d.di_version = 2; /* * We've already zeroed the old link count, the projid field, * and the pad field. */ } /* * Project ids won't be stored on disk if we are using a version 1 inode. */ if ((prid != 0) && (ip->i_d.di_version == 1)) xfs_bump_ino_vers2(tp, ip); if (pip && XFS_INHERIT_GID(pip)) { ip->i_d.di_gid = pip->i_d.di_gid; if ((pip->i_d.di_mode & S_ISGID) && S_ISDIR(mode)) { ip->i_d.di_mode |= S_ISGID; } } /* * If the group ID of the new file does not match the effective group * ID or one of the supplementary group IDs, the S_ISGID bit is cleared * (and only if the irix_sgid_inherit compatibility variable is set). */ if ((irix_sgid_inherit) && (ip->i_d.di_mode & S_ISGID) && (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid)))) { ip->i_d.di_mode &= ~S_ISGID; } ip->i_d.di_size = 0; ip->i_d.di_nextents = 0; ASSERT(ip->i_d.di_nblocks == 0); nanotime(&tv); ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec; ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec; ip->i_d.di_atime = ip->i_d.di_mtime; ip->i_d.di_ctime = ip->i_d.di_mtime; /* * di_gen will have been taken care of in xfs_iread. */ ip->i_d.di_extsize = 0; ip->i_d.di_dmevmask = 0; ip->i_d.di_dmstate = 0; ip->i_d.di_flags = 0; if (ip->i_d.di_version == 3) { ASSERT(ip->i_d.di_ino == ino); ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid)); ip->i_d.di_crc = 0; ip->i_d.di_changecount = 1; ip->i_d.di_lsn = 0; ip->i_d.di_flags2 = 0; memset(&(ip->i_d.di_pad2[0]), 0, sizeof(ip->i_d.di_pad2)); ip->i_d.di_crtime = ip->i_d.di_mtime; } flags = XFS_ILOG_CORE; switch (mode & S_IFMT) { case S_IFIFO: case S_IFCHR: case S_IFBLK: case S_IFSOCK: ip->i_d.di_format = XFS_DINODE_FMT_DEV; ip->i_df.if_u2.if_rdev = rdev; ip->i_df.if_flags = 0; flags |= XFS_ILOG_DEV; break; case S_IFREG: /* * we can't set up filestreams until after the VFS inode * is set up properly. */ if (pip && xfs_inode_is_filestream(pip)) filestreams = 1; /* fall through */ case S_IFDIR: if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) { uint di_flags = 0; if (S_ISDIR(mode)) { if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT) di_flags |= XFS_DIFLAG_RTINHERIT; if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) { di_flags |= XFS_DIFLAG_EXTSZINHERIT; ip->i_d.di_extsize = pip->i_d.di_extsize; } } else if (S_ISREG(mode)) { if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT) di_flags |= XFS_DIFLAG_REALTIME; if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) { di_flags |= XFS_DIFLAG_EXTSIZE; ip->i_d.di_extsize = pip->i_d.di_extsize; } } if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) && xfs_inherit_noatime) di_flags |= XFS_DIFLAG_NOATIME; if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) && xfs_inherit_nodump) di_flags |= XFS_DIFLAG_NODUMP; if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) && xfs_inherit_sync) di_flags |= XFS_DIFLAG_SYNC; if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) && xfs_inherit_nosymlinks) di_flags |= XFS_DIFLAG_NOSYMLINKS; if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) di_flags |= XFS_DIFLAG_PROJINHERIT; if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) && xfs_inherit_nodefrag) di_flags |= XFS_DIFLAG_NODEFRAG; if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM) di_flags |= XFS_DIFLAG_FILESTREAM; ip->i_d.di_flags |= di_flags; } /* FALLTHROUGH */ case S_IFLNK: ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS; ip->i_df.if_flags = XFS_IFEXTENTS; ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0; ip->i_df.if_u1.if_extents = NULL; break; default: ASSERT(0); } /* * Attribute fork settings for new inode. */ ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS; ip->i_d.di_anextents = 0; /* * Log the new values stuffed into the inode. */ xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); xfs_trans_log_inode(tp, ip, flags); /* now that we have an i_mode we can setup inode ops and unlock */ xfs_setup_inode(ip); /* now we have set up the vfs inode we can associate the filestream */ if (filestreams) { error = xfs_filestream_associate(pip, ip); if (error < 0) return -error; if (!error) xfs_iflags_set(ip, XFS_IFILESTREAM); } *ipp = ip; return 0; } /* * Allocates a new inode from disk and return a pointer to the * incore copy. This routine will internally commit the current * transaction and allocate a new one if the Space Manager needed * to do an allocation to replenish the inode free-list. * * This routine is designed to be called from xfs_create and * xfs_create_dir. * */ int xfs_dir_ialloc( xfs_trans_t **tpp, /* input: current transaction; output: may be a new transaction. */ xfs_inode_t *dp, /* directory within whose allocate the inode. */ umode_t mode, xfs_nlink_t nlink, xfs_dev_t rdev, prid_t prid, /* project id */ int okalloc, /* ok to allocate new space */ xfs_inode_t **ipp, /* pointer to inode; it will be locked. */ int *committed) { xfs_trans_t *tp; xfs_trans_t *ntp; xfs_inode_t *ip; xfs_buf_t *ialloc_context = NULL; int code; void *dqinfo; uint tflags; tp = *tpp; ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES); /* * xfs_ialloc will return a pointer to an incore inode if * the Space Manager has an available inode on the free * list. Otherwise, it will do an allocation and replenish * the freelist. Since we can only do one allocation per * transaction without deadlocks, we will need to commit the * current transaction and start a new one. We will then * need to call xfs_ialloc again to get the inode. * * If xfs_ialloc did an allocation to replenish the freelist, * it returns the bp containing the head of the freelist as * ialloc_context. We will hold a lock on it across the * transaction commit so that no other process can steal * the inode(s) that we've just allocated. */ code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc, &ialloc_context, &ip); /* * Return an error if we were unable to allocate a new inode. * This should only happen if we run out of space on disk or * encounter a disk error. */ if (code) { *ipp = NULL; return code; } if (!ialloc_context && !ip) { *ipp = NULL; return XFS_ERROR(ENOSPC); } /* * If the AGI buffer is non-NULL, then we were unable to get an * inode in one operation. We need to commit the current * transaction and call xfs_ialloc() again. It is guaranteed * to succeed the second time. */ if (ialloc_context) { struct xfs_trans_res tres; /* * Normally, xfs_trans_commit releases all the locks. * We call bhold to hang on to the ialloc_context across * the commit. Holding this buffer prevents any other * processes from doing any allocations in this * allocation group. */ xfs_trans_bhold(tp, ialloc_context); /* * Save the log reservation so we can use * them in the next transaction. */ tres.tr_logres = xfs_trans_get_log_res(tp); tres.tr_logcount = xfs_trans_get_log_count(tp); /* * We want the quota changes to be associated with the next * transaction, NOT this one. So, detach the dqinfo from this * and attach it to the next transaction. */ dqinfo = NULL; tflags = 0; if (tp->t_dqinfo) { dqinfo = (void *)tp->t_dqinfo; tp->t_dqinfo = NULL; tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY; tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY); } ntp = xfs_trans_dup(tp); code = xfs_trans_commit(tp, 0); tp = ntp; if (committed != NULL) { *committed = 1; } /* * If we get an error during the commit processing, * release the buffer that is still held and return * to the caller. */ if (code) { xfs_buf_relse(ialloc_context); if (dqinfo) { tp->t_dqinfo = dqinfo; xfs_trans_free_dqinfo(tp); } *tpp = ntp; *ipp = NULL; return code; } /* * transaction commit worked ok so we can drop the extra ticket * reference that we gained in xfs_trans_dup() */ xfs_log_ticket_put(tp->t_ticket); tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; code = xfs_trans_reserve(tp, &tres, 0, 0); /* * Re-attach the quota info that we detached from prev trx. */ if (dqinfo) { tp->t_dqinfo = dqinfo; tp->t_flags |= tflags; } if (code) { xfs_buf_relse(ialloc_context); *tpp = ntp; *ipp = NULL; return code; } xfs_trans_bjoin(tp, ialloc_context); /* * Call ialloc again. Since we've locked out all * other allocations in this allocation group, * this call should always succeed. */ code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc, &ialloc_context, &ip); /* * If we get an error at this point, return to the caller * so that the current transaction can be aborted. */ if (code) { *tpp = tp; *ipp = NULL; return code; } ASSERT(!ialloc_context && ip); } else { if (committed != NULL) *committed = 0; } *ipp = ip; *tpp = tp; return 0; } /* * Decrement the link count on an inode & log the change. * If this causes the link count to go to zero, initiate the * logging activity required to truncate a file. */ int /* error */ xfs_droplink( xfs_trans_t *tp, xfs_inode_t *ip) { int error; xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); ASSERT (ip->i_d.di_nlink > 0); ip->i_d.di_nlink--; drop_nlink(VFS_I(ip)); xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); error = 0; if (ip->i_d.di_nlink == 0) { /* * We're dropping the last link to this file. * Move the on-disk inode to the AGI unlinked list. * From xfs_inactive() we will pull the inode from * the list and free it. */ error = xfs_iunlink(tp, ip); } return error; } /* * This gets called when the inode's version needs to be changed from 1 to 2. * Currently this happens when the nlink field overflows the old 16-bit value * or when chproj is called to change the project for the first time. * As a side effect the superblock version will also get rev'd * to contain the NLINK bit. */ void xfs_bump_ino_vers2( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_mount_t *mp; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); ASSERT(ip->i_d.di_version == 1); ip->i_d.di_version = 2; ip->i_d.di_onlink = 0; memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad)); mp = tp->t_mountp; if (!xfs_sb_version_hasnlink(&mp->m_sb)) { spin_lock(&mp->m_sb_lock); if (!xfs_sb_version_hasnlink(&mp->m_sb)) { xfs_sb_version_addnlink(&mp->m_sb); spin_unlock(&mp->m_sb_lock); xfs_mod_sb(tp, XFS_SB_VERSIONNUM); } else { spin_unlock(&mp->m_sb_lock); } } /* Caller must log the inode */ } /* * Increment the link count on an inode & log the change. */ int xfs_bumplink( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); ASSERT(ip->i_d.di_nlink > 0); ip->i_d.di_nlink++; inc_nlink(VFS_I(ip)); if ((ip->i_d.di_version == 1) && (ip->i_d.di_nlink > XFS_MAXLINK_1)) { /* * The inode has increased its number of links beyond * what can fit in an old format inode. It now needs * to be converted to a version 2 inode with a 32 bit * link count. If this is the first inode in the file * system to do this, then we need to bump the superblock * version number as well. */ xfs_bump_ino_vers2(tp, ip); } xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); return 0; } int xfs_create( xfs_inode_t *dp, struct xfs_name *name, umode_t mode, xfs_dev_t rdev, xfs_inode_t **ipp) { int is_dir = S_ISDIR(mode); struct xfs_mount *mp = dp->i_mount; struct xfs_inode *ip = NULL; struct xfs_trans *tp = NULL; int error; xfs_bmap_free_t free_list; xfs_fsblock_t first_block; bool unlock_dp_on_error = false; uint cancel_flags; int committed; prid_t prid; struct xfs_dquot *udqp = NULL; struct xfs_dquot *gdqp = NULL; struct xfs_dquot *pdqp = NULL; struct xfs_trans_res tres; uint resblks; trace_xfs_create(dp, name); if (XFS_FORCED_SHUTDOWN(mp)) return XFS_ERROR(EIO); if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) prid = xfs_get_projid(dp); else prid = XFS_PROJID_DEFAULT; /* * Make sure that we have allocated dquot(s) on disk. */ error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()), xfs_kgid_to_gid(current_fsgid()), prid, XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp, &pdqp); if (error) return error; if (is_dir) { rdev = 0; resblks = XFS_MKDIR_SPACE_RES(mp, name->len); tres.tr_logres = M_RES(mp)->tr_mkdir.tr_logres; tres.tr_logcount = XFS_MKDIR_LOG_COUNT; tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR); } else { resblks = XFS_CREATE_SPACE_RES(mp, name->len); tres.tr_logres = M_RES(mp)->tr_create.tr_logres; tres.tr_logcount = XFS_CREATE_LOG_COUNT; tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE); } cancel_flags = XFS_TRANS_RELEASE_LOG_RES; /* * Initially assume that the file does not exist and * reserve the resources for that case. If that is not * the case we'll drop the one we have and get a more * appropriate transaction later. */ tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; error = xfs_trans_reserve(tp, &tres, resblks, 0); if (error == ENOSPC) { /* flush outstanding delalloc blocks and retry */ xfs_flush_inodes(mp); error = xfs_trans_reserve(tp, &tres, resblks, 0); } if (error == ENOSPC) { /* No space at all so try a "no-allocation" reservation */ resblks = 0; error = xfs_trans_reserve(tp, &tres, 0, 0); } if (error) { cancel_flags = 0; goto out_trans_cancel; } xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT); unlock_dp_on_error = true; xfs_bmap_init(&free_list, &first_block); /* * Reserve disk quota and the inode. */ error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, pdqp, resblks, 1, 0); if (error) goto out_trans_cancel; error = xfs_dir_canenter(tp, dp, name, resblks); if (error) goto out_trans_cancel; /* * A newly created regular or special file just has one directory * entry pointing to them, but a directory also the "." entry * pointing to itself. */ error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, resblks > 0, &ip, &committed); if (error) { if (error == ENOSPC) goto out_trans_cancel; goto out_trans_abort; } /* * Now we join the directory inode to the transaction. We do not do it * earlier because xfs_dir_ialloc might commit the previous transaction * (and release all the locks). An error from here on will result in * the transaction cancel unlocking dp so don't do it explicitly in the * error path. */ xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL); unlock_dp_on_error = false; error = xfs_dir_createname(tp, dp, name, ip->i_ino, &first_block, &free_list, resblks ? resblks - XFS_IALLOC_SPACE_RES(mp) : 0); if (error) { ASSERT(error != ENOSPC); goto out_trans_abort; } xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE); if (is_dir) { error = xfs_dir_init(tp, ip, dp); if (error) goto out_bmap_cancel; error = xfs_bumplink(tp, dp); if (error) goto out_bmap_cancel; } /* * If this is a synchronous mount, make sure that the * create transaction goes to disk before returning to * the user. */ if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) xfs_trans_set_sync(tp); /* * Attach the dquot(s) to the inodes and modify them incore. * These ids of the inode couldn't have changed since the new * inode has been locked ever since it was created. */ xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp); error = xfs_bmap_finish(&tp, &free_list, &committed); if (error) goto out_bmap_cancel; error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); if (error) goto out_release_inode; xfs_qm_dqrele(udqp); xfs_qm_dqrele(gdqp); xfs_qm_dqrele(pdqp); *ipp = ip; return 0; out_bmap_cancel: xfs_bmap_cancel(&free_list); out_trans_abort: cancel_flags |= XFS_TRANS_ABORT; out_trans_cancel: xfs_trans_cancel(tp, cancel_flags); out_release_inode: /* * Wait until after the current transaction is aborted to * release the inode. This prevents recursive transactions * and deadlocks from xfs_inactive. */ if (ip) IRELE(ip); xfs_qm_dqrele(udqp); xfs_qm_dqrele(gdqp); xfs_qm_dqrele(pdqp); if (unlock_dp_on_error) xfs_iunlock(dp, XFS_ILOCK_EXCL); return error; } int xfs_link( xfs_inode_t *tdp, xfs_inode_t *sip, struct xfs_name *target_name) { xfs_mount_t *mp = tdp->i_mount; xfs_trans_t *tp; int error; xfs_bmap_free_t free_list; xfs_fsblock_t first_block; int cancel_flags; int committed; int resblks; trace_xfs_link(tdp, target_name); ASSERT(!S_ISDIR(sip->i_d.di_mode)); if (XFS_FORCED_SHUTDOWN(mp)) return XFS_ERROR(EIO); error = xfs_qm_dqattach(sip, 0); if (error) goto std_return; error = xfs_qm_dqattach(tdp, 0); if (error) goto std_return; tp = xfs_trans_alloc(mp, XFS_TRANS_LINK); cancel_flags = XFS_TRANS_RELEASE_LOG_RES; resblks = XFS_LINK_SPACE_RES(mp, target_name->len); error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, resblks, 0); if (error == ENOSPC) { resblks = 0; error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, 0, 0); } if (error) { cancel_flags = 0; goto error_return; } xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL); /* * If we are using project inheritance, we only allow hard link * creation in our tree when the project IDs are the same; else * the tree quota mechanism could be circumvented. */ if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) && (xfs_get_projid(tdp) != xfs_get_projid(sip)))) { error = XFS_ERROR(EXDEV); goto error_return; } error = xfs_dir_canenter(tp, tdp, target_name, resblks); if (error) goto error_return; xfs_bmap_init(&free_list, &first_block); error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino, &first_block, &free_list, resblks); if (error) goto abort_return; xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE); error = xfs_bumplink(tp, sip); if (error) goto abort_return; /* * If this is a synchronous mount, make sure that the * link transaction goes to disk before returning to * the user. */ if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) { xfs_trans_set_sync(tp); } error = xfs_bmap_finish (&tp, &free_list, &committed); if (error) { xfs_bmap_cancel(&free_list); goto abort_return; } return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); abort_return: cancel_flags |= XFS_TRANS_ABORT; error_return: xfs_trans_cancel(tp, cancel_flags); std_return: return error; } /* * Free up the underlying blocks past new_size. The new size must be smaller * than the current size. This routine can be used both for the attribute and * data fork, and does not modify the inode size, which is left to the caller. * * The transaction passed to this routine must have made a permanent log * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the * given transaction and start new ones, so make sure everything involved in * the transaction is tidy before calling here. Some transaction will be * returned to the caller to be committed. The incoming transaction must * already include the inode, and both inode locks must be held exclusively. * The inode must also be "held" within the transaction. On return the inode * will be "held" within the returned transaction. This routine does NOT * require any disk space to be reserved for it within the transaction. * * If we get an error, we must return with the inode locked and linked into the * current transaction. This keeps things simple for the higher level code, * because it always knows that the inode is locked and held in the transaction * that returns to it whether errors occur or not. We don't mark the inode * dirty on error so that transactions can be easily aborted if possible. */ int xfs_itruncate_extents( struct xfs_trans **tpp, struct xfs_inode *ip, int whichfork, xfs_fsize_t new_size) { struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp = *tpp; struct xfs_trans *ntp; xfs_bmap_free_t free_list; xfs_fsblock_t first_block; xfs_fileoff_t first_unmap_block; xfs_fileoff_t last_block; xfs_filblks_t unmap_len; int committed; int error = 0; int done = 0; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); ASSERT(!atomic_read(&VFS_I(ip)->i_count) || xfs_isilocked(ip, XFS_IOLOCK_EXCL)); ASSERT(new_size <= XFS_ISIZE(ip)); ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES); ASSERT(ip->i_itemp != NULL); ASSERT(ip->i_itemp->ili_lock_flags == 0); ASSERT(!XFS_NOT_DQATTACHED(mp, ip)); trace_xfs_itruncate_extents_start(ip, new_size); /* * Since it is possible for space to become allocated beyond * the end of the file (in a crash where the space is allocated * but the inode size is not yet updated), simply remove any * blocks which show up between the new EOF and the maximum * possible file size. If the first block to be removed is * beyond the maximum file size (ie it is the same as last_block), * then there is nothing to do. */ first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size); last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); if (first_unmap_block == last_block) return 0; ASSERT(first_unmap_block < last_block); unmap_len = last_block - first_unmap_block + 1; while (!done) { xfs_bmap_init(&free_list, &first_block); error = xfs_bunmapi(tp, ip, first_unmap_block, unmap_len, xfs_bmapi_aflag(whichfork), XFS_ITRUNC_MAX_EXTENTS, &first_block, &free_list, &done); if (error) goto out_bmap_cancel; /* * Duplicate the transaction that has the permanent * reservation and commit the old transaction. */ error = xfs_bmap_finish(&tp, &free_list, &committed); if (committed) xfs_trans_ijoin(tp, ip, 0); if (error) goto out_bmap_cancel; if (committed) { /* * Mark the inode dirty so it will be logged and * moved forward in the log as part of every commit. */ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); } ntp = xfs_trans_dup(tp); error = xfs_trans_commit(tp, 0); tp = ntp; xfs_trans_ijoin(tp, ip, 0); if (error) goto out; /* * Transaction commit worked ok so we can drop the extra ticket * reference that we gained in xfs_trans_dup() */ xfs_log_ticket_put(tp->t_ticket); error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0); if (error) goto out; } /* * Always re-log the inode so that our permanent transaction can keep * on rolling it forward in the log. */ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); trace_xfs_itruncate_extents_end(ip, new_size); out: *tpp = tp; return error; out_bmap_cancel: /* * If the bunmapi call encounters an error, return to the caller where * the transaction can be properly aborted. We just need to make sure * we're not holding any resources that we were not when we came in. */ xfs_bmap_cancel(&free_list); goto out; } int xfs_release( xfs_inode_t *ip) { xfs_mount_t *mp = ip->i_mount; int error; if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0)) return 0; /* If this is a read-only mount, don't do this (would generate I/O) */ if (mp->m_flags & XFS_MOUNT_RDONLY) return 0; if (!XFS_FORCED_SHUTDOWN(mp)) { int truncated; /* * If we are using filestreams, and we have an unlinked * file that we are processing the last close on, then nothing * will be able to reopen and write to this file. Purge this * inode from the filestreams cache so that it doesn't delay * teardown of the inode. */ if ((ip->i_d.di_nlink == 0) && xfs_inode_is_filestream(ip)) xfs_filestream_deassociate(ip); /* * If we previously truncated this file and removed old data * in the process, we want to initiate "early" writeout on * the last close. This is an attempt to combat the notorious * NULL files problem which is particularly noticeable from a * truncate down, buffered (re-)write (delalloc), followed by * a crash. What we are effectively doing here is * significantly reducing the time window where we'd otherwise * be exposed to that problem. */ truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED); if (truncated) { xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE); if (VN_DIRTY(VFS_I(ip)) && ip->i_delayed_blks > 0) { error = -filemap_flush(VFS_I(ip)->i_mapping); if (error) return error; } } } if (ip->i_d.di_nlink == 0) return 0; if (xfs_can_free_eofblocks(ip, false)) { /* * If we can't get the iolock just skip truncating the blocks * past EOF because we could deadlock with the mmap_sem * otherwise. We'll get another chance to drop them once the * last reference to the inode is dropped, so we'll never leak * blocks permanently. * * Further, check if the inode is being opened, written and * closed frequently and we have delayed allocation blocks * outstanding (e.g. streaming writes from the NFS server), * truncating the blocks past EOF will cause fragmentation to * occur. * * In this case don't do the truncation, either, but we have to * be careful how we detect this case. Blocks beyond EOF show * up as i_delayed_blks even when the inode is clean, so we * need to truncate them away first before checking for a dirty * release. Hence on the first dirty close we will still remove * the speculative allocation, but after that we will leave it * in place. */ if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE)) return 0; error = xfs_free_eofblocks(mp, ip, true); if (error && error != EAGAIN) return error; /* delalloc blocks after truncation means it really is dirty */ if (ip->i_delayed_blks) xfs_iflags_set(ip, XFS_IDIRTY_RELEASE); } return 0; } /* * xfs_inactive * * This is called when the vnode reference count for the vnode * goes to zero. If the file has been unlinked, then it must * now be truncated. Also, we clear all of the read-ahead state * kept for the inode here since the file is now closed. */ int xfs_inactive( xfs_inode_t *ip) { xfs_bmap_free_t free_list; xfs_fsblock_t first_block; int committed; struct xfs_trans *tp; struct xfs_mount *mp; struct xfs_trans_res *resp; int error; int truncate = 0; /* * If the inode is already free, then there can be nothing * to clean up here. */ if (ip->i_d.di_mode == 0 || is_bad_inode(VFS_I(ip))) { ASSERT(ip->i_df.if_real_bytes == 0); ASSERT(ip->i_df.if_broot_bytes == 0); return VN_INACTIVE_CACHE; } mp = ip->i_mount; error = 0; /* If this is a read-only mount, don't do this (would generate I/O) */ if (mp->m_flags & XFS_MOUNT_RDONLY) goto out; if (ip->i_d.di_nlink != 0) { /* * force is true because we are evicting an inode from the * cache. Post-eof blocks must be freed, lest we end up with * broken free space accounting. */ if (xfs_can_free_eofblocks(ip, true)) { error = xfs_free_eofblocks(mp, ip, false); if (error) return VN_INACTIVE_CACHE; } goto out; } if (S_ISREG(ip->i_d.di_mode) && (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 || ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0)) truncate = 1; error = xfs_qm_dqattach(ip, 0); if (error) return VN_INACTIVE_CACHE; tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE); resp = (truncate || S_ISLNK(ip->i_d.di_mode)) ? &M_RES(mp)->tr_itruncate : &M_RES(mp)->tr_ifree; error = xfs_trans_reserve(tp, resp, 0, 0); if (error) { ASSERT(XFS_FORCED_SHUTDOWN(mp)); xfs_trans_cancel(tp, 0); return VN_INACTIVE_CACHE; } xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); if (S_ISLNK(ip->i_d.di_mode)) { error = xfs_inactive_symlink(ip, &tp); if (error) goto out_cancel; } else if (truncate) { ip->i_d.di_size = 0; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0); if (error) goto out_cancel; ASSERT(ip->i_d.di_nextents == 0); } /* * If there are attributes associated with the file then blow them away * now. The code calls a routine that recursively deconstructs the * attribute fork. We need to just commit the current transaction * because we can't use it for xfs_attr_inactive(). */ if (ip->i_d.di_anextents > 0) { ASSERT(ip->i_d.di_forkoff != 0); error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); if (error) goto out_unlock; xfs_iunlock(ip, XFS_ILOCK_EXCL); error = xfs_attr_inactive(ip); if (error) goto out; tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE); error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree, 0, 0); if (error) { xfs_trans_cancel(tp, 0); goto out; } xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); } if (ip->i_afp) xfs_idestroy_fork(ip, XFS_ATTR_FORK); ASSERT(ip->i_d.di_anextents == 0); /* * Free the inode. */ xfs_bmap_init(&free_list, &first_block); error = xfs_ifree(tp, ip, &free_list); if (error) { /* * If we fail to free the inode, shut down. The cancel * might do that, we need to make sure. Otherwise the * inode might be lost for a long time or forever. */ if (!XFS_FORCED_SHUTDOWN(mp)) { xfs_notice(mp, "%s: xfs_ifree returned error %d", __func__, error); xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR); } xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT); } else { /* * Credit the quota account(s). The inode is gone. */ xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1); /* * Just ignore errors at this point. There is nothing we can * do except to try to keep going. Make sure it's not a silent * error. */ error = xfs_bmap_finish(&tp, &free_list, &committed); if (error) xfs_notice(mp, "%s: xfs_bmap_finish returned error %d", __func__, error); error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); if (error) xfs_notice(mp, "%s: xfs_trans_commit returned error %d", __func__, error); } /* * Release the dquots held by inode, if any. */ xfs_qm_dqdetach(ip); out_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); out: return VN_INACTIVE_CACHE; out_cancel: xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); goto out_unlock; } /* * This is called when the inode's link count goes to 0. * We place the on-disk inode on a list in the AGI. It * will be pulled from this list when the inode is freed. */ int xfs_iunlink( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_mount_t *mp; xfs_agi_t *agi; xfs_dinode_t *dip; xfs_buf_t *agibp; xfs_buf_t *ibp; xfs_agino_t agino; short bucket_index; int offset; int error; ASSERT(ip->i_d.di_nlink == 0); ASSERT(ip->i_d.di_mode != 0); mp = tp->t_mountp; /* * Get the agi buffer first. It ensures lock ordering * on the list. */ error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp); if (error) return error; agi = XFS_BUF_TO_AGI(agibp); /* * Get the index into the agi hash table for the * list this inode will go on. */ agino = XFS_INO_TO_AGINO(mp, ip->i_ino); ASSERT(agino != 0); bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; ASSERT(agi->agi_unlinked[bucket_index]); ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino); if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) { /* * There is already another inode in the bucket we need * to add ourselves to. Add us at the front of the list. * Here we put the head pointer into our next pointer, * and then we fall through to point the head at us. */ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0, 0); if (error) return error; ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO)); dip->di_next_unlinked = agi->agi_unlinked[bucket_index]; offset = ip->i_imap.im_boffset + offsetof(xfs_dinode_t, di_next_unlinked); /* need to recalc the inode CRC if appropriate */ xfs_dinode_calc_crc(mp, dip); xfs_trans_inode_buf(tp, ibp); xfs_trans_log_buf(tp, ibp, offset, (offset + sizeof(xfs_agino_t) - 1)); xfs_inobp_check(mp, ibp); } /* * Point the bucket head pointer at the inode being inserted. */ ASSERT(agino != 0); agi->agi_unlinked[bucket_index] = cpu_to_be32(agino); offset = offsetof(xfs_agi_t, agi_unlinked) + (sizeof(xfs_agino_t) * bucket_index); xfs_trans_log_buf(tp, agibp, offset, (offset + sizeof(xfs_agino_t) - 1)); return 0; } /* * Pull the on-disk inode from the AGI unlinked list. */ STATIC int xfs_iunlink_remove( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_ino_t next_ino; xfs_mount_t *mp; xfs_agi_t *agi; xfs_dinode_t *dip; xfs_buf_t *agibp; xfs_buf_t *ibp; xfs_agnumber_t agno; xfs_agino_t agino; xfs_agino_t next_agino; xfs_buf_t *last_ibp; xfs_dinode_t *last_dip = NULL; short bucket_index; int offset, last_offset = 0; int error; mp = tp->t_mountp; agno = XFS_INO_TO_AGNO(mp, ip->i_ino); /* * Get the agi buffer first. It ensures lock ordering * on the list. */ error = xfs_read_agi(mp, tp, agno, &agibp); if (error) return error; agi = XFS_BUF_TO_AGI(agibp); /* * Get the index into the agi hash table for the * list this inode will go on. */ agino = XFS_INO_TO_AGINO(mp, ip->i_ino); ASSERT(agino != 0); bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)); ASSERT(agi->agi_unlinked[bucket_index]); if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) { /* * We're at the head of the list. Get the inode's on-disk * buffer to see if there is anyone after us on the list. * Only modify our next pointer if it is not already NULLAGINO. * This saves us the overhead of dealing with the buffer when * there is no need to change it. */ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0, 0); if (error) { xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.", __func__, error); return error; } next_agino = be32_to_cpu(dip->di_next_unlinked); ASSERT(next_agino != 0); if (next_agino != NULLAGINO) { dip->di_next_unlinked = cpu_to_be32(NULLAGINO); offset = ip->i_imap.im_boffset + offsetof(xfs_dinode_t, di_next_unlinked); /* need to recalc the inode CRC if appropriate */ xfs_dinode_calc_crc(mp, dip); xfs_trans_inode_buf(tp, ibp); xfs_trans_log_buf(tp, ibp, offset, (offset + sizeof(xfs_agino_t) - 1)); xfs_inobp_check(mp, ibp); } else { xfs_trans_brelse(tp, ibp); } /* * Point the bucket head pointer at the next inode. */ ASSERT(next_agino != 0); ASSERT(next_agino != agino); agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino); offset = offsetof(xfs_agi_t, agi_unlinked) + (sizeof(xfs_agino_t) * bucket_index); xfs_trans_log_buf(tp, agibp, offset, (offset + sizeof(xfs_agino_t) - 1)); } else { /* * We need to search the list for the inode being freed. */ next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]); last_ibp = NULL; while (next_agino != agino) { struct xfs_imap imap; if (last_ibp) xfs_trans_brelse(tp, last_ibp); imap.im_blkno = 0; next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino); error = xfs_imap(mp, tp, next_ino, &imap, 0); if (error) { xfs_warn(mp, "%s: xfs_imap returned error %d.", __func__, error); return error; } error = xfs_imap_to_bp(mp, tp, &imap, &last_dip, &last_ibp, 0, 0); if (error) { xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.", __func__, error); return error; } last_offset = imap.im_boffset; next_agino = be32_to_cpu(last_dip->di_next_unlinked); ASSERT(next_agino != NULLAGINO); ASSERT(next_agino != 0); } /* * Now last_ibp points to the buffer previous to us on the * unlinked list. Pull us from the list. */ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0, 0); if (error) { xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.", __func__, error); return error; } next_agino = be32_to_cpu(dip->di_next_unlinked); ASSERT(next_agino != 0); ASSERT(next_agino != agino); if (next_agino != NULLAGINO) { dip->di_next_unlinked = cpu_to_be32(NULLAGINO); offset = ip->i_imap.im_boffset + offsetof(xfs_dinode_t, di_next_unlinked); /* need to recalc the inode CRC if appropriate */ xfs_dinode_calc_crc(mp, dip); xfs_trans_inode_buf(tp, ibp); xfs_trans_log_buf(tp, ibp, offset, (offset + sizeof(xfs_agino_t) - 1)); xfs_inobp_check(mp, ibp); } else { xfs_trans_brelse(tp, ibp); } /* * Point the previous inode on the list to the next inode. */ last_dip->di_next_unlinked = cpu_to_be32(next_agino); ASSERT(next_agino != 0); offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked); /* need to recalc the inode CRC if appropriate */ xfs_dinode_calc_crc(mp, last_dip); xfs_trans_inode_buf(tp, last_ibp); xfs_trans_log_buf(tp, last_ibp, offset, (offset + sizeof(xfs_agino_t) - 1)); xfs_inobp_check(mp, last_ibp); } return 0; } /* * A big issue when freeing the inode cluster is is that we _cannot_ skip any * inodes that are in memory - they all must be marked stale and attached to * the cluster buffer. */ STATIC int xfs_ifree_cluster( xfs_inode_t *free_ip, xfs_trans_t *tp, xfs_ino_t inum) { xfs_mount_t *mp = free_ip->i_mount; int blks_per_cluster; int nbufs; int ninodes; int i, j; xfs_daddr_t blkno; xfs_buf_t *bp; xfs_inode_t *ip; xfs_inode_log_item_t *iip; xfs_log_item_t *lip; struct xfs_perag *pag; pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum)); if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) { blks_per_cluster = 1; ninodes = mp->m_sb.sb_inopblock; nbufs = XFS_IALLOC_BLOCKS(mp); } else { blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) / mp->m_sb.sb_blocksize; ninodes = blks_per_cluster * mp->m_sb.sb_inopblock; nbufs = XFS_IALLOC_BLOCKS(mp) / blks_per_cluster; } for (j = 0; j < nbufs; j++, inum += ninodes) { blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum), XFS_INO_TO_AGBNO(mp, inum)); /* * We obtain and lock the backing buffer first in the process * here, as we have to ensure that any dirty inode that we * can't get the flush lock on is attached to the buffer. * If we scan the in-memory inodes first, then buffer IO can * complete before we get a lock on it, and hence we may fail * to mark all the active inodes on the buffer stale. */ bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno, mp->m_bsize * blks_per_cluster, XBF_UNMAPPED); if (!bp) return ENOMEM; /* * This buffer may not have been correctly initialised as we * didn't read it from disk. That's not important because we are * only using to mark the buffer as stale in the log, and to * attach stale cached inodes on it. That means it will never be * dispatched for IO. If it is, we want to know about it, and we * want it to fail. We can acheive this by adding a write * verifier to the buffer. */ bp->b_ops = &xfs_inode_buf_ops; /* * Walk the inodes already attached to the buffer and mark them * stale. These will all have the flush locks held, so an * in-memory inode walk can't lock them. By marking them all * stale first, we will not attempt to lock them in the loop * below as the XFS_ISTALE flag will be set. */ lip = bp->b_fspriv; while (lip) { if (lip->li_type == XFS_LI_INODE) { iip = (xfs_inode_log_item_t *)lip; ASSERT(iip->ili_logged == 1); lip->li_cb = xfs_istale_done; xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn, &iip->ili_item.li_lsn); xfs_iflags_set(iip->ili_inode, XFS_ISTALE); } lip = lip->li_bio_list; } /* * For each inode in memory attempt to add it to the inode * buffer and set it up for being staled on buffer IO * completion. This is safe as we've locked out tail pushing * and flushing by locking the buffer. * * We have already marked every inode that was part of a * transaction stale above, which means there is no point in * even trying to lock them. */ for (i = 0; i < ninodes; i++) { retry: rcu_read_lock(); ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, (inum + i))); /* Inode not in memory, nothing to do */ if (!ip) { rcu_read_unlock(); continue; } /* * because this is an RCU protected lookup, we could * find a recently freed or even reallocated inode * during the lookup. We need to check under the * i_flags_lock for a valid inode here. Skip it if it * is not valid, the wrong inode or stale. */ spin_lock(&ip->i_flags_lock); if (ip->i_ino != inum + i || __xfs_iflags_test(ip, XFS_ISTALE)) { spin_unlock(&ip->i_flags_lock); rcu_read_unlock(); continue; } spin_unlock(&ip->i_flags_lock); /* * Don't try to lock/unlock the current inode, but we * _cannot_ skip the other inodes that we did not find * in the list attached to the buffer and are not * already marked stale. If we can't lock it, back off * and retry. */ if (ip != free_ip && !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) { rcu_read_unlock(); delay(1); goto retry; } rcu_read_unlock(); xfs_iflock(ip); xfs_iflags_set(ip, XFS_ISTALE); /* * we don't need to attach clean inodes or those only * with unlogged changes (which we throw away, anyway). */ iip = ip->i_itemp; if (!iip || xfs_inode_clean(ip)) { ASSERT(ip != free_ip); xfs_ifunlock(ip); xfs_iunlock(ip, XFS_ILOCK_EXCL); continue; } iip->ili_last_fields = iip->ili_fields; iip->ili_fields = 0; iip->ili_logged = 1; xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn, &iip->ili_item.li_lsn); xfs_buf_attach_iodone(bp, xfs_istale_done, &iip->ili_item); if (ip != free_ip) xfs_iunlock(ip, XFS_ILOCK_EXCL); } xfs_trans_stale_inode_buf(tp, bp); xfs_trans_binval(tp, bp); } xfs_perag_put(pag); return 0; } /* * This is called to return an inode to the inode free list. * The inode should already be truncated to 0 length and have * no pages associated with it. This routine also assumes that * the inode is already a part of the transaction. * * The on-disk copy of the inode will have been added to the list * of unlinked inodes in the AGI. We need to remove the inode from * that list atomically with respect to freeing it here. */ int xfs_ifree( xfs_trans_t *tp, xfs_inode_t *ip, xfs_bmap_free_t *flist) { int error; int delete; xfs_ino_t first_ino; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); ASSERT(ip->i_d.di_nlink == 0); ASSERT(ip->i_d.di_nextents == 0); ASSERT(ip->i_d.di_anextents == 0); ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode)); ASSERT(ip->i_d.di_nblocks == 0); /* * Pull the on-disk inode from the AGI unlinked list. */ error = xfs_iunlink_remove(tp, ip); if (error) return error; error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino); if (error) return error; ip->i_d.di_mode = 0; /* mark incore inode as free */ ip->i_d.di_flags = 0; ip->i_d.di_dmevmask = 0; ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */ ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS; ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS; /* * Bump the generation count so no one will be confused * by reincarnations of this inode. */ ip->i_d.di_gen++; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); if (delete) error = xfs_ifree_cluster(ip, tp, first_ino); return error; } /* * This is called to unpin an inode. The caller must have the inode locked * in at least shared mode so that the buffer cannot be subsequently pinned * once someone is waiting for it to be unpinned. */ static void xfs_iunpin( struct xfs_inode *ip) { ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); trace_xfs_inode_unpin_nowait(ip, _RET_IP_); /* Give the log a push to start the unpinning I/O */ xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0); } static void __xfs_iunpin_wait( struct xfs_inode *ip) { wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT); DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT); xfs_iunpin(ip); do { prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); if (xfs_ipincount(ip)) io_schedule(); } while (xfs_ipincount(ip)); finish_wait(wq, &wait.wait); } void xfs_iunpin_wait( struct xfs_inode *ip) { if (xfs_ipincount(ip)) __xfs_iunpin_wait(ip); } int xfs_remove( xfs_inode_t *dp, struct xfs_name *name, xfs_inode_t *ip) { xfs_mount_t *mp = dp->i_mount; xfs_trans_t *tp = NULL; int is_dir = S_ISDIR(ip->i_d.di_mode); int error = 0; xfs_bmap_free_t free_list; xfs_fsblock_t first_block; int cancel_flags; int committed; int link_zero; uint resblks; uint log_count; trace_xfs_remove(dp, name); if (XFS_FORCED_SHUTDOWN(mp)) return XFS_ERROR(EIO); error = xfs_qm_dqattach(dp, 0); if (error) goto std_return; error = xfs_qm_dqattach(ip, 0); if (error) goto std_return; if (is_dir) { tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR); log_count = XFS_DEFAULT_LOG_COUNT; } else { tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE); log_count = XFS_REMOVE_LOG_COUNT; } cancel_flags = XFS_TRANS_RELEASE_LOG_RES; /* * We try to get the real space reservation first, * allowing for directory btree deletion(s) implying * possible bmap insert(s). If we can't get the space * reservation then we use 0 instead, and avoid the bmap * btree insert(s) in the directory code by, if the bmap * insert tries to happen, instead trimming the LAST * block from the directory. */ resblks = XFS_REMOVE_SPACE_RES(mp); error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, resblks, 0); if (error == ENOSPC) { resblks = 0; error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, 0, 0); } if (error) { ASSERT(error != ENOSPC); cancel_flags = 0; goto out_trans_cancel; } xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); /* * If we're removing a directory perform some additional validation. */ if (is_dir) { ASSERT(ip->i_d.di_nlink >= 2); if (ip->i_d.di_nlink != 2) { error = XFS_ERROR(ENOTEMPTY); goto out_trans_cancel; } if (!xfs_dir_isempty(ip)) { error = XFS_ERROR(ENOTEMPTY); goto out_trans_cancel; } } xfs_bmap_init(&free_list, &first_block); error = xfs_dir_removename(tp, dp, name, ip->i_ino, &first_block, &free_list, resblks); if (error) { ASSERT(error != ENOENT); goto out_bmap_cancel; } xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); if (is_dir) { /* * Drop the link from ip's "..". */ error = xfs_droplink(tp, dp); if (error) goto out_bmap_cancel; /* * Drop the "." link from ip to self. */ error = xfs_droplink(tp, ip); if (error) goto out_bmap_cancel; } else { /* * When removing a non-directory we need to log the parent * inode here. For a directory this is done implicitly * by the xfs_droplink call for the ".." entry. */ xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE); } /* * Drop the link from dp to ip. */ error = xfs_droplink(tp, ip); if (error) goto out_bmap_cancel; /* * Determine if this is the last link while * we are in the transaction. */ link_zero = (ip->i_d.di_nlink == 0); /* * If this is a synchronous mount, make sure that the * remove transaction goes to disk before returning to * the user. */ if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) xfs_trans_set_sync(tp); error = xfs_bmap_finish(&tp, &free_list, &committed); if (error) goto out_bmap_cancel; error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); if (error) goto std_return; /* * If we are using filestreams, kill the stream association. * If the file is still open it may get a new one but that * will get killed on last close in xfs_close() so we don't * have to worry about that. */ if (!is_dir && link_zero && xfs_inode_is_filestream(ip)) xfs_filestream_deassociate(ip); return 0; out_bmap_cancel: xfs_bmap_cancel(&free_list); cancel_flags |= XFS_TRANS_ABORT; out_trans_cancel: xfs_trans_cancel(tp, cancel_flags); std_return: return error; } /* * Enter all inodes for a rename transaction into a sorted array. */ STATIC void xfs_sort_for_rename( xfs_inode_t *dp1, /* in: old (source) directory inode */ xfs_inode_t *dp2, /* in: new (target) directory inode */ xfs_inode_t *ip1, /* in: inode of old entry */ xfs_inode_t *ip2, /* in: inode of new entry, if it already exists, NULL otherwise. */ xfs_inode_t **i_tab,/* out: array of inode returned, sorted */ int *num_inodes) /* out: number of inodes in array */ { xfs_inode_t *temp; int i, j; /* * i_tab contains a list of pointers to inodes. We initialize * the table here & we'll sort it. We will then use it to * order the acquisition of the inode locks. * * Note that the table may contain duplicates. e.g., dp1 == dp2. */ i_tab[0] = dp1; i_tab[1] = dp2; i_tab[2] = ip1; if (ip2) { *num_inodes = 4; i_tab[3] = ip2; } else { *num_inodes = 3; i_tab[3] = NULL; } /* * Sort the elements via bubble sort. (Remember, there are at * most 4 elements to sort, so this is adequate.) */ for (i = 0; i < *num_inodes; i++) { for (j = 1; j < *num_inodes; j++) { if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) { temp = i_tab[j]; i_tab[j] = i_tab[j-1]; i_tab[j-1] = temp; } } } } /* * xfs_rename */ int xfs_rename( xfs_inode_t *src_dp, struct xfs_name *src_name, xfs_inode_t *src_ip, xfs_inode_t *target_dp, struct xfs_name *target_name, xfs_inode_t *target_ip) { xfs_trans_t *tp = NULL; xfs_mount_t *mp = src_dp->i_mount; int new_parent; /* moving to a new dir */ int src_is_directory; /* src_name is a directory */ int error; xfs_bmap_free_t free_list; xfs_fsblock_t first_block; int cancel_flags; int committed; xfs_inode_t *inodes[4]; int spaceres; int num_inodes; trace_xfs_rename(src_dp, target_dp, src_name, target_name); new_parent = (src_dp != target_dp); src_is_directory = S_ISDIR(src_ip->i_d.di_mode); xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, inodes, &num_inodes); xfs_bmap_init(&free_list, &first_block); tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME); cancel_flags = XFS_TRANS_RELEASE_LOG_RES; spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len); error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, spaceres, 0); if (error == ENOSPC) { spaceres = 0; error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, 0, 0); } if (error) { xfs_trans_cancel(tp, 0); goto std_return; } /* * Attach the dquots to the inodes */ error = xfs_qm_vop_rename_dqattach(inodes); if (error) { xfs_trans_cancel(tp, cancel_flags); goto std_return; } /* * Lock all the participating inodes. Depending upon whether * the target_name exists in the target directory, and * whether the target directory is the same as the source * directory, we can lock from 2 to 4 inodes. */ xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL); /* * Join all the inodes to the transaction. From this point on, * we can rely on either trans_commit or trans_cancel to unlock * them. */ xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL); if (new_parent) xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL); if (target_ip) xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL); /* * If we are using project inheritance, we only allow renames * into our tree when the project IDs are the same; else the * tree quota mechanism would be circumvented. */ if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) && (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) { error = XFS_ERROR(EXDEV); goto error_return; } /* * Set up the target. */ if (target_ip == NULL) { /* * If there's no space reservation, check the entry will * fit before actually inserting it. */ error = xfs_dir_canenter(tp, target_dp, target_name, spaceres); if (error) goto error_return; /* * If target does not exist and the rename crosses * directories, adjust the target directory link count * to account for the ".." reference from the new entry. */ error = xfs_dir_createname(tp, target_dp, target_name, src_ip->i_ino, &first_block, &free_list, spaceres); if (error == ENOSPC) goto error_return; if (error) goto abort_return; xfs_trans_ichgtime(tp, target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); if (new_parent && src_is_directory) { error = xfs_bumplink(tp, target_dp); if (error) goto abort_return; } } else { /* target_ip != NULL */ /* * If target exists and it's a directory, check that both * target and source are directories and that target can be * destroyed, or that neither is a directory. */ if (S_ISDIR(target_ip->i_d.di_mode)) { /* * Make sure target dir is empty. */ if (!(xfs_dir_isempty(target_ip)) || (target_ip->i_d.di_nlink > 2)) { error = XFS_ERROR(EEXIST); goto error_return; } } /* * Link the source inode under the target name. * If the source inode is a directory and we are moving * it across directories, its ".." entry will be * inconsistent until we replace that down below. * * In case there is already an entry with the same * name at the destination directory, remove it first. */ error = xfs_dir_replace(tp, target_dp, target_name, src_ip->i_ino, &first_block, &free_list, spaceres); if (error) goto abort_return; xfs_trans_ichgtime(tp, target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); /* * Decrement the link count on the target since the target * dir no longer points to it. */ error = xfs_droplink(tp, target_ip); if (error) goto abort_return; if (src_is_directory) { /* * Drop the link from the old "." entry. */ error = xfs_droplink(tp, target_ip); if (error) goto abort_return; } } /* target_ip != NULL */ /* * Remove the source. */ if (new_parent && src_is_directory) { /* * Rewrite the ".." entry to point to the new * directory. */ error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot, target_dp->i_ino, &first_block, &free_list, spaceres); ASSERT(error != EEXIST); if (error) goto abort_return; } /* * We always want to hit the ctime on the source inode. * * This isn't strictly required by the standards since the source * inode isn't really being changed, but old unix file systems did * it and some incremental backup programs won't work without it. */ xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE); /* * Adjust the link count on src_dp. This is necessary when * renaming a directory, either within one parent when * the target existed, or across two parent directories. */ if (src_is_directory && (new_parent || target_ip != NULL)) { /* * Decrement link count on src_directory since the * entry that's moved no longer points to it. */ error = xfs_droplink(tp, src_dp); if (error) goto abort_return; } error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino, &first_block, &free_list, spaceres); if (error) goto abort_return; xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE); if (new_parent) xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE); /* * If this is a synchronous mount, make sure that the * rename transaction goes to disk before returning to * the user. */ if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) { xfs_trans_set_sync(tp); } error = xfs_bmap_finish(&tp, &free_list, &committed); if (error) { xfs_bmap_cancel(&free_list); xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT)); goto std_return; } /* * trans_commit will unlock src_ip, target_ip & decrement * the vnode references. */ return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); abort_return: cancel_flags |= XFS_TRANS_ABORT; error_return: xfs_bmap_cancel(&free_list); xfs_trans_cancel(tp, cancel_flags); std_return: return error; } STATIC int xfs_iflush_cluster( xfs_inode_t *ip, xfs_buf_t *bp) { xfs_mount_t *mp = ip->i_mount; struct xfs_perag *pag; unsigned long first_index, mask; unsigned long inodes_per_cluster; int ilist_size; xfs_inode_t **ilist; xfs_inode_t *iq; int nr_found; int clcount = 0; int bufwasdelwri; int i; pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino)); inodes_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog; ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *); ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS); if (!ilist) goto out_put; mask = ~(((XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)) - 1); first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask; rcu_read_lock(); /* really need a gang lookup range call here */ nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist, first_index, inodes_per_cluster); if (nr_found == 0) goto out_free; for (i = 0; i < nr_found; i++) { iq = ilist[i]; if (iq == ip) continue; /* * because this is an RCU protected lookup, we could find a * recently freed or even reallocated inode during the lookup. * We need to check under the i_flags_lock for a valid inode * here. Skip it if it is not valid or the wrong inode. */ spin_lock(&ip->i_flags_lock); if (!ip->i_ino || (XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) { spin_unlock(&ip->i_flags_lock); continue; } spin_unlock(&ip->i_flags_lock); /* * Do an un-protected check to see if the inode is dirty and * is a candidate for flushing. These checks will be repeated * later after the appropriate locks are acquired. */ if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0) continue; /* * Try to get locks. If any are unavailable or it is pinned, * then this inode cannot be flushed and is skipped. */ if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED)) continue; if (!xfs_iflock_nowait(iq)) { xfs_iunlock(iq, XFS_ILOCK_SHARED); continue; } if (xfs_ipincount(iq)) { xfs_ifunlock(iq); xfs_iunlock(iq, XFS_ILOCK_SHARED); continue; } /* * arriving here means that this inode can be flushed. First * re-check that it's dirty before flushing. */ if (!xfs_inode_clean(iq)) { int error; error = xfs_iflush_int(iq, bp); if (error) { xfs_iunlock(iq, XFS_ILOCK_SHARED); goto cluster_corrupt_out; } clcount++; } else { xfs_ifunlock(iq); } xfs_iunlock(iq, XFS_ILOCK_SHARED); } if (clcount) { XFS_STATS_INC(xs_icluster_flushcnt); XFS_STATS_ADD(xs_icluster_flushinode, clcount); } out_free: rcu_read_unlock(); kmem_free(ilist); out_put: xfs_perag_put(pag); return 0; cluster_corrupt_out: /* * Corruption detected in the clustering loop. Invalidate the * inode buffer and shut down the filesystem. */ rcu_read_unlock(); /* * Clean up the buffer. If it was delwri, just release it -- * brelse can handle it with no problems. If not, shut down the * filesystem before releasing the buffer. */ bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q); if (bufwasdelwri) xfs_buf_relse(bp); xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); if (!bufwasdelwri) { /* * Just like incore_relse: if we have b_iodone functions, * mark the buffer as an error and call them. Otherwise * mark it as stale and brelse. */ if (bp->b_iodone) { XFS_BUF_UNDONE(bp); xfs_buf_stale(bp); xfs_buf_ioerror(bp, EIO); xfs_buf_ioend(bp, 0); } else { xfs_buf_stale(bp); xfs_buf_relse(bp); } } /* * Unlocks the flush lock */ xfs_iflush_abort(iq, false); kmem_free(ilist); xfs_perag_put(pag); return XFS_ERROR(EFSCORRUPTED); } /* * Flush dirty inode metadata into the backing buffer. * * The caller must have the inode lock and the inode flush lock held. The * inode lock will still be held upon return to the caller, and the inode * flush lock will be released after the inode has reached the disk. * * The caller must write out the buffer returned in *bpp and release it. */ int xfs_iflush( struct xfs_inode *ip, struct xfs_buf **bpp) { struct xfs_mount *mp = ip->i_mount; struct xfs_buf *bp; struct xfs_dinode *dip; int error; XFS_STATS_INC(xs_iflush_count); ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); ASSERT(xfs_isiflocked(ip)); ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE || ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)); *bpp = NULL; xfs_iunpin_wait(ip); /* * For stale inodes we cannot rely on the backing buffer remaining * stale in cache for the remaining life of the stale inode and so * xfs_imap_to_bp() below may give us a buffer that no longer contains * inodes below. We have to check this after ensuring the inode is * unpinned so that it is safe to reclaim the stale inode after the * flush call. */ if (xfs_iflags_test(ip, XFS_ISTALE)) { xfs_ifunlock(ip); return 0; } /* * This may have been unpinned because the filesystem is shutting * down forcibly. If that's the case we must not write this inode * to disk, because the log record didn't make it to disk. * * We also have to remove the log item from the AIL in this case, * as we wait for an empty AIL as part of the unmount process. */ if (XFS_FORCED_SHUTDOWN(mp)) { error = XFS_ERROR(EIO); goto abort_out; } /* * Get the buffer containing the on-disk inode. */ error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK, 0); if (error || !bp) { xfs_ifunlock(ip); return error; } /* * First flush out the inode that xfs_iflush was called with. */ error = xfs_iflush_int(ip, bp); if (error) goto corrupt_out; /* * If the buffer is pinned then push on the log now so we won't * get stuck waiting in the write for too long. */ if (xfs_buf_ispinned(bp)) xfs_log_force(mp, 0); /* * inode clustering: * see if other inodes can be gathered into this write */ error = xfs_iflush_cluster(ip, bp); if (error) goto cluster_corrupt_out; *bpp = bp; return 0; corrupt_out: xfs_buf_relse(bp); xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); cluster_corrupt_out: error = XFS_ERROR(EFSCORRUPTED); abort_out: /* * Unlocks the flush lock */ xfs_iflush_abort(ip, false); return error; } STATIC int xfs_iflush_int( struct xfs_inode *ip, struct xfs_buf *bp) { struct xfs_inode_log_item *iip = ip->i_itemp; struct xfs_dinode *dip; struct xfs_mount *mp = ip->i_mount; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); ASSERT(xfs_isiflocked(ip)); ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE || ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)); ASSERT(iip != NULL && iip->ili_fields != 0); /* set *dip = inode's place in the buffer */ dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset); if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC), mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad inode %Lu magic number 0x%x, ptr 0x%p", __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip); goto corrupt_out; } if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC, mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x", __func__, ip->i_ino, ip, ip->i_d.di_magic); goto corrupt_out; } if (S_ISREG(ip->i_d.di_mode)) { if (XFS_TEST_ERROR( (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) && (ip->i_d.di_format != XFS_DINODE_FMT_BTREE), mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad regular inode %Lu, ptr 0x%p", __func__, ip->i_ino, ip); goto corrupt_out; } } else if (S_ISDIR(ip->i_d.di_mode)) { if (XFS_TEST_ERROR( (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) && (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) && (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL), mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad directory inode %Lu, ptr 0x%p", __func__, ip->i_ino, ip); goto corrupt_out; } } if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents > ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5, XFS_RANDOM_IFLUSH_5)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: detected corrupt incore inode %Lu, " "total extents = %d, nblocks = %Ld, ptr 0x%p", __func__, ip->i_ino, ip->i_d.di_nextents + ip->i_d.di_anextents, ip->i_d.di_nblocks, ip); goto corrupt_out; } if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize, mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p", __func__, ip->i_ino, ip->i_d.di_forkoff, ip); goto corrupt_out; } /* * Inode item log recovery for v1/v2 inodes are dependent on the * di_flushiter count for correct sequencing. We bump the flush * iteration count so we can detect flushes which postdate a log record * during recovery. This is redundant as we now log every change and * hence this can't happen but we need to still do it to ensure * backwards compatibility with old kernels that predate logging all * inode changes. */ if (ip->i_d.di_version < 3) ip->i_d.di_flushiter++; /* * Copy the dirty parts of the inode into the on-disk * inode. We always copy out the core of the inode, * because if the inode is dirty at all the core must * be. */ xfs_dinode_to_disk(dip, &ip->i_d); /* Wrap, we never let the log put out DI_MAX_FLUSH */ if (ip->i_d.di_flushiter == DI_MAX_FLUSH) ip->i_d.di_flushiter = 0; /* * If this is really an old format inode and the superblock version * has not been updated to support only new format inodes, then * convert back to the old inode format. If the superblock version * has been updated, then make the conversion permanent. */ ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb)); if (ip->i_d.di_version == 1) { if (!xfs_sb_version_hasnlink(&mp->m_sb)) { /* * Convert it back. */ ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1); dip->di_onlink = cpu_to_be16(ip->i_d.di_nlink); } else { /* * The superblock version has already been bumped, * so just make the conversion to the new inode * format permanent. */ ip->i_d.di_version = 2; dip->di_version = 2; ip->i_d.di_onlink = 0; dip->di_onlink = 0; memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad)); memset(&(dip->di_pad[0]), 0, sizeof(dip->di_pad)); ASSERT(xfs_get_projid(ip) == 0); } } xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp); if (XFS_IFORK_Q(ip)) xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp); xfs_inobp_check(mp, bp); /* * We've recorded everything logged in the inode, so we'd like to clear * the ili_fields bits so we don't log and flush things unnecessarily. * However, we can't stop logging all this information until the data * we've copied into the disk buffer is written to disk. If we did we * might overwrite the copy of the inode in the log with all the data * after re-logging only part of it, and in the face of a crash we * wouldn't have all the data we need to recover. * * What we do is move the bits to the ili_last_fields field. When * logging the inode, these bits are moved back to the ili_fields field. * In the xfs_iflush_done() routine we clear ili_last_fields, since we * know that the information those bits represent is permanently on * disk. As long as the flush completes before the inode is logged * again, then both ili_fields and ili_last_fields will be cleared. * * We can play with the ili_fields bits here, because the inode lock * must be held exclusively in order to set bits there and the flush * lock protects the ili_last_fields bits. Set ili_logged so the flush * done routine can tell whether or not to look in the AIL. Also, store * the current LSN of the inode so that we can tell whether the item has * moved in the AIL from xfs_iflush_done(). In order to read the lsn we * need the AIL lock, because it is a 64 bit value that cannot be read * atomically. */ iip->ili_last_fields = iip->ili_fields; iip->ili_fields = 0; iip->ili_logged = 1; xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn, &iip->ili_item.li_lsn); /* * Attach the function xfs_iflush_done to the inode's * buffer. This will remove the inode from the AIL * and unlock the inode's flush lock when the inode is * completely written to disk. */ xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item); /* update the lsn in the on disk inode if required */ if (ip->i_d.di_version == 3) dip->di_lsn = cpu_to_be64(iip->ili_item.li_lsn); /* generate the checksum. */ xfs_dinode_calc_crc(mp, dip); ASSERT(bp->b_fspriv != NULL); ASSERT(bp->b_iodone != NULL); return 0; corrupt_out: return XFS_ERROR(EFSCORRUPTED); }