// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2000-2006 Silicon Graphics, Inc. * All Rights Reserved. */ #include #include "xfs.h" #include "xfs_fs.h" #include "xfs_shared.h" #include "xfs_format.h" #include "xfs_log_format.h" #include "xfs_trans_resv.h" #include "xfs_sb.h" #include "xfs_mount.h" #include "xfs_defer.h" #include "xfs_inode.h" #include "xfs_dir2.h" #include "xfs_attr.h" #include "xfs_trans_space.h" #include "xfs_trans.h" #include "xfs_buf_item.h" #include "xfs_inode_item.h" #include "xfs_ialloc.h" #include "xfs_bmap.h" #include "xfs_bmap_util.h" #include "xfs_errortag.h" #include "xfs_error.h" #include "xfs_quota.h" #include "xfs_filestream.h" #include "xfs_trace.h" #include "xfs_icache.h" #include "xfs_symlink.h" #include "xfs_trans_priv.h" #include "xfs_log.h" #include "xfs_bmap_btree.h" #include "xfs_reflink.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_iunlink(struct xfs_trans *, struct xfs_inode *); STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *); /* * helper function to extract extent size hint from inode */ xfs_extlen_t xfs_get_extsz_hint( struct xfs_inode *ip) { /* * No point in aligning allocations if we need to COW to actually * write to them. */ if (xfs_is_always_cow_inode(ip)) return 0; 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; } /* * Helper function to extract CoW extent size hint from inode. * Between the extent size hint and the CoW extent size hint, we * return the greater of the two. If the value is zero (automatic), * use the default size. */ xfs_extlen_t xfs_get_cowextsz_hint( struct xfs_inode *ip) { xfs_extlen_t a, b; a = 0; if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) a = ip->i_d.di_cowextsize; b = xfs_get_extsz_hint(ip); a = max(a, b); if (a == 0) return XFS_DEFAULT_COWEXTSZ_HINT; return a; } /* * These two are wrapper routines around the xfs_ilock() routine used to * centralize some grungy code. They are used in places that wish to lock the * inode solely for reading the extents. The reason these places can't just * call xfs_ilock(ip, 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 functions return a value which should be given to the corresponding * xfs_iunlock() call. */ uint xfs_ilock_data_map_shared( struct xfs_inode *ip) { uint lock_mode = XFS_ILOCK_SHARED; if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE && (ip->i_df.if_flags & XFS_IFEXTENTS) == 0) lock_mode = XFS_ILOCK_EXCL; xfs_ilock(ip, lock_mode); return lock_mode; } uint xfs_ilock_attr_map_shared( struct xfs_inode *ip) { uint lock_mode = XFS_ILOCK_SHARED; if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_BTREE && (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0) lock_mode = XFS_ILOCK_EXCL; xfs_ilock(ip, lock_mode); return lock_mode; } /* * In addition to i_rwsem in the VFS inode, the xfs inode contains 2 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows * various combinations of the locks to be obtained. * * The 3 locks should always be ordered so that the IO lock is obtained first, * the mmap lock second and the ilock last in order to prevent deadlock. * * Basic locking order: * * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock * * mmap_lock locking order: * * i_rwsem -> page lock -> mmap_lock * mmap_lock -> i_mmap_lock -> page_lock * * The difference in mmap_lock locking order mean that we cannot hold the * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can * fault in pages during copy in/out (for buffered IO) or require the mmap_lock * in get_user_pages() to map the user pages into the kernel address space for * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because * page faults already hold the mmap_lock. * * Hence to serialise fully against both syscall and mmap based IO, we need to * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both * taken in places where we need to invalidate the page cache in a race * free manner (e.g. truncate, hole punch and other extent manipulation * functions). */ 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_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) != (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) { down_write_nested(&VFS_I(ip)->i_rwsem, XFS_IOLOCK_DEP(lock_flags)); } else if (lock_flags & XFS_IOLOCK_SHARED) { down_read_nested(&VFS_I(ip)->i_rwsem, XFS_IOLOCK_DEP(lock_flags)); } if (lock_flags & XFS_MMAPLOCK_EXCL) mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags)); else if (lock_flags & XFS_MMAPLOCK_SHARED) mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_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_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) != (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) { if (!down_write_trylock(&VFS_I(ip)->i_rwsem)) goto out; } else if (lock_flags & XFS_IOLOCK_SHARED) { if (!down_read_trylock(&VFS_I(ip)->i_rwsem)) goto out; } if (lock_flags & XFS_MMAPLOCK_EXCL) { if (!mrtryupdate(&ip->i_mmaplock)) goto out_undo_iolock; } else if (lock_flags & XFS_MMAPLOCK_SHARED) { if (!mrtryaccess(&ip->i_mmaplock)) goto out_undo_iolock; } if (lock_flags & XFS_ILOCK_EXCL) { if (!mrtryupdate(&ip->i_lock)) goto out_undo_mmaplock; } else if (lock_flags & XFS_ILOCK_SHARED) { if (!mrtryaccess(&ip->i_lock)) goto out_undo_mmaplock; } return 1; out_undo_mmaplock: if (lock_flags & XFS_MMAPLOCK_EXCL) mrunlock_excl(&ip->i_mmaplock); else if (lock_flags & XFS_MMAPLOCK_SHARED) mrunlock_shared(&ip->i_mmaplock); out_undo_iolock: if (lock_flags & XFS_IOLOCK_EXCL) up_write(&VFS_I(ip)->i_rwsem); else if (lock_flags & XFS_IOLOCK_SHARED) up_read(&VFS_I(ip)->i_rwsem); 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_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) != (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); ASSERT(lock_flags != 0); if (lock_flags & XFS_IOLOCK_EXCL) up_write(&VFS_I(ip)->i_rwsem); else if (lock_flags & XFS_IOLOCK_SHARED) up_read(&VFS_I(ip)->i_rwsem); if (lock_flags & XFS_MMAPLOCK_EXCL) mrunlock_excl(&ip->i_mmaplock); else if (lock_flags & XFS_MMAPLOCK_SHARED) mrunlock_shared(&ip->i_mmaplock); 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_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)); ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); if (lock_flags & XFS_ILOCK_EXCL) mrdemote(&ip->i_lock); if (lock_flags & XFS_MMAPLOCK_EXCL) mrdemote(&ip->i_mmaplock); if (lock_flags & XFS_IOLOCK_EXCL) downgrade_write(&VFS_I(ip)->i_rwsem); 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_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) { if (!(lock_flags & XFS_MMAPLOCK_SHARED)) return !!ip->i_mmaplock.mr_writer; return rwsem_is_locked(&ip->i_mmaplock.mr_lock); } if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) { if (!(lock_flags & XFS_IOLOCK_SHARED)) return !debug_locks || lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0); return rwsem_is_locked(&VFS_I(ip)->i_rwsem); } ASSERT(0); return 0; } #endif /* * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build * errors and warnings. */ #if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP) static bool xfs_lockdep_subclass_ok( int subclass) { return subclass < MAX_LOCKDEP_SUBCLASSES; } #else #define xfs_lockdep_subclass_ok(subclass) (true) #endif /* * Bump the subclass so xfs_lock_inodes() acquires each lock with a different * value. This can be called for any type of inode lock combination, including * parent locking. Care must be taken to ensure we don't overrun the subclass * storage fields in the class mask we build. */ static inline int xfs_lock_inumorder(int lock_mode, int subclass) { int class = 0; ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP | XFS_ILOCK_RTSUM))); ASSERT(xfs_lockdep_subclass_ok(subclass)); if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) { ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS); class += subclass << XFS_IOLOCK_SHIFT; } if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) { ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS); class += subclass << XFS_MMAPLOCK_SHIFT; } if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) { ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS); class += subclass << XFS_ILOCK_SHIFT; } return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class; } /* * 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. * * xfs_lock_inodes() can only be used to lock one type of lock at a time - * the iolock, the mmaplock or the ilock, but not more than one at a time. If we * lock more than one at a time, lockdep will report false positives saying we * have violated locking orders. */ static void xfs_lock_inodes( struct xfs_inode **ips, int inodes, uint lock_mode) { int attempts = 0, i, j, try_lock; struct xfs_log_item *lp; /* * Currently supports between 2 and 5 inodes with exclusive locking. We * support an arbitrary depth of locking here, but absolute limits on * inodes depend on the type of locking and the limits placed by * lockdep annotations in xfs_lock_inumorder. These are all checked by * the asserts. */ ASSERT(ips && inodes >= 2 && inodes <= 5); ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)); ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED | XFS_ILOCK_SHARED))); ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) || inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1); ASSERT(!(lock_mode & XFS_ILOCK_EXCL) || inodes <= XFS_ILOCK_MAX_SUBCLASS + 1); if (lock_mode & XFS_IOLOCK_EXCL) { ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL))); } else if (lock_mode & XFS_MMAPLOCK_EXCL) ASSERT(!(lock_mode & XFS_ILOCK_EXCL)); 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 = &ips[j]->i_itemp->ili_item; if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) 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) { xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i)); continue; } /* 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))) continue; /* * Unlock all previous guys and try again. xfs_iunlock will try * to push the tail if the inode is in the AIL. */ attempts++; 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 */ } i = 0; try_lock = 0; goto again; } } /* * xfs_lock_two_inodes() can only be used to lock one type of lock at a time - * the mmaplock or the ilock, but not more than one type at a time. If we lock * more than one at a time, lockdep will report false positives saying we have * violated locking orders. The iolock must be double-locked separately since * we use i_rwsem for that. We now support taking one lock EXCL and the other * SHARED. */ void xfs_lock_two_inodes( struct xfs_inode *ip0, uint ip0_mode, struct xfs_inode *ip1, uint ip1_mode) { struct xfs_inode *temp; uint mode_temp; int attempts = 0; struct xfs_log_item *lp; ASSERT(hweight32(ip0_mode) == 1); ASSERT(hweight32(ip1_mode) == 1); ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))); ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))); ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); ASSERT(ip0->i_ino != ip1->i_ino); if (ip0->i_ino > ip1->i_ino) { temp = ip0; ip0 = ip1; ip1 = temp; mode_temp = ip0_mode; ip0_mode = ip1_mode; ip1_mode = mode_temp; } again: xfs_ilock(ip0, xfs_lock_inumorder(ip0_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 = &ip0->i_itemp->ili_item; if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) { if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) { xfs_iunlock(ip0, ip0_mode); if ((++attempts % 5) == 0) delay(1); /* Don't just spin the CPU */ goto again; } } else { xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1)); } } STATIC uint _xfs_dic2xflags( uint16_t di_flags, uint64_t di_flags2, bool has_attr) { uint flags = 0; if (di_flags & XFS_DIFLAG_ANY) { if (di_flags & XFS_DIFLAG_REALTIME) flags |= FS_XFLAG_REALTIME; if (di_flags & XFS_DIFLAG_PREALLOC) flags |= FS_XFLAG_PREALLOC; if (di_flags & XFS_DIFLAG_IMMUTABLE) flags |= FS_XFLAG_IMMUTABLE; if (di_flags & XFS_DIFLAG_APPEND) flags |= FS_XFLAG_APPEND; if (di_flags & XFS_DIFLAG_SYNC) flags |= FS_XFLAG_SYNC; if (di_flags & XFS_DIFLAG_NOATIME) flags |= FS_XFLAG_NOATIME; if (di_flags & XFS_DIFLAG_NODUMP) flags |= FS_XFLAG_NODUMP; if (di_flags & XFS_DIFLAG_RTINHERIT) flags |= FS_XFLAG_RTINHERIT; if (di_flags & XFS_DIFLAG_PROJINHERIT) flags |= FS_XFLAG_PROJINHERIT; if (di_flags & XFS_DIFLAG_NOSYMLINKS) flags |= FS_XFLAG_NOSYMLINKS; if (di_flags & XFS_DIFLAG_EXTSIZE) flags |= FS_XFLAG_EXTSIZE; if (di_flags & XFS_DIFLAG_EXTSZINHERIT) flags |= FS_XFLAG_EXTSZINHERIT; if (di_flags & XFS_DIFLAG_NODEFRAG) flags |= FS_XFLAG_NODEFRAG; if (di_flags & XFS_DIFLAG_FILESTREAM) flags |= FS_XFLAG_FILESTREAM; } if (di_flags2 & XFS_DIFLAG2_ANY) { if (di_flags2 & XFS_DIFLAG2_DAX) flags |= FS_XFLAG_DAX; if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE) flags |= FS_XFLAG_COWEXTSIZE; } if (has_attr) flags |= FS_XFLAG_HASATTR; return flags; } uint xfs_ip2xflags( struct xfs_inode *ip) { struct xfs_icdinode *dic = &ip->i_d; return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip)); } /* * 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; trace_xfs_lookup(dp, name); if (XFS_FORCED_SHUTDOWN(dp->i_mount)) return -EIO; error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name); if (error) goto out_unlock; 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_unlock: *ipp = NULL; return error; } /* Propagate di_flags from a parent inode to a child inode. */ static void xfs_inode_inherit_flags( struct xfs_inode *ip, const struct xfs_inode *pip) { unsigned int di_flags = 0; umode_t mode = VFS_I(ip)->i_mode; 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; } if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) di_flags |= XFS_DIFLAG_PROJINHERIT; } else if (S_ISREG(mode)) { if ((pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT) && xfs_sb_version_hasrealtime(&ip->i_mount->m_sb)) 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_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; } /* Propagate di_flags2 from a parent inode to a child inode. */ static void xfs_inode_inherit_flags2( struct xfs_inode *ip, const struct xfs_inode *pip) { if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) { ip->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE; ip->i_d.di_cowextsize = pip->i_d.di_cowextsize; } if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX) ip->i_d.di_flags2 |= XFS_DIFLAG2_DAX; } /* * Initialise a newly allocated inode and return the in-core inode to the * caller locked exclusively. */ static int xfs_init_new_inode( struct user_namespace *mnt_userns, struct xfs_trans *tp, struct xfs_inode *pip, xfs_ino_t ino, umode_t mode, xfs_nlink_t nlink, dev_t rdev, prid_t prid, bool init_xattrs, struct xfs_inode **ipp) { struct inode *dir = pip ? VFS_I(pip) : NULL; struct xfs_mount *mp = tp->t_mountp; struct xfs_inode *ip; unsigned int flags; int error; struct timespec64 tv; struct inode *inode; /* * Protect against obviously corrupt allocation btree records. Later * xfs_iget checks will catch re-allocation of other active in-memory * and on-disk inodes. If we don't catch reallocating the parent inode * here we will deadlock in xfs_iget() so we have to do these checks * first. */ if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) { xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino); return -EFSCORRUPTED; } /* * Get the in-core inode with the lock held exclusively 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); inode = VFS_I(ip); set_nlink(inode, nlink); inode->i_rdev = rdev; ip->i_d.di_projid = prid; if (dir && !(dir->i_mode & S_ISGID) && (mp->m_flags & XFS_MOUNT_GRPID)) { inode->i_uid = fsuid_into_mnt(mnt_userns); inode->i_gid = dir->i_gid; inode->i_mode = mode; } else { inode_init_owner(mnt_userns, inode, dir, mode); } /* * 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 && (inode->i_mode & S_ISGID) && !in_group_p(i_gid_into_mnt(mnt_userns, inode))) inode->i_mode &= ~S_ISGID; ip->i_d.di_size = 0; ip->i_df.if_nextents = 0; ASSERT(ip->i_d.di_nblocks == 0); tv = current_time(inode); inode->i_mtime = tv; inode->i_atime = tv; inode->i_ctime = tv; 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 (xfs_sb_version_has_v3inode(&mp->m_sb)) { inode_set_iversion(inode, 1); ip->i_d.di_flags2 = mp->m_ino_geo.new_diflags2; ip->i_d.di_cowextsize = 0; ip->i_d.di_crtime = tv; } flags = XFS_ILOG_CORE; switch (mode & S_IFMT) { case S_IFIFO: case S_IFCHR: case S_IFBLK: case S_IFSOCK: ip->i_df.if_format = XFS_DINODE_FMT_DEV; ip->i_df.if_flags = 0; flags |= XFS_ILOG_DEV; break; case S_IFREG: case S_IFDIR: if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) xfs_inode_inherit_flags(ip, pip); if (pip && (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY)) xfs_inode_inherit_flags2(ip, pip); /* FALLTHROUGH */ case S_IFLNK: ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS; ip->i_df.if_flags = XFS_IFEXTENTS; ip->i_df.if_bytes = 0; ip->i_df.if_u1.if_root = NULL; break; default: ASSERT(0); } /* * If we need to create attributes immediately after allocating the * inode, initialise an empty attribute fork right now. We use the * default fork offset for attributes here as we don't know exactly what * size or how many attributes we might be adding. We can do this * safely here because we know the data fork is completely empty and * this saves us from needing to run a separate transaction to set the * fork offset in the immediate future. */ if (init_xattrs) { ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3; ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 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 the inode structure */ xfs_setup_inode(ip); *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 we needed to allocate more on-disk free inodes to perform the requested * operation. * * If we are allocating quota inodes, we do not have a parent inode to attach to * or associate with (i.e. dp == NULL) because they are not linked into the * directory structure - they are attached directly to the superblock - and so * have no parent. */ int xfs_dir_ialloc( struct user_namespace *mnt_userns, struct xfs_trans **tpp, struct xfs_inode *dp, umode_t mode, xfs_nlink_t nlink, dev_t rdev, prid_t prid, bool init_xattrs, struct xfs_inode **ipp) { struct xfs_buf *agibp; xfs_ino_t parent_ino = dp ? dp->i_ino : 0; xfs_ino_t ino; int error; ASSERT((*tpp)->t_flags & XFS_TRANS_PERM_LOG_RES); /* * Call the space management code to pick the on-disk inode to be * allocated. */ error = xfs_dialloc_select_ag(tpp, parent_ino, mode, &agibp); if (error) return error; if (!agibp) return -ENOSPC; /* Allocate an inode from the selected AG */ error = xfs_dialloc_ag(*tpp, agibp, parent_ino, &ino); if (error) return error; ASSERT(ino != NULLFSINO); return xfs_init_new_inode(mnt_userns, *tpp, dp, ino, mode, nlink, rdev, prid, init_xattrs, ipp); } /* * Decrement the link count on an inode & log the change. If this causes the * link count to go to zero, move the inode to AGI unlinked list so that it can * be freed when the last active reference goes away via xfs_inactive(). */ static int /* error */ xfs_droplink( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); drop_nlink(VFS_I(ip)); xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); if (VFS_I(ip)->i_nlink) return 0; return xfs_iunlink(tp, ip); } /* * Increment the link count on an inode & log the change. */ static void xfs_bumplink( xfs_trans_t *tp, xfs_inode_t *ip) { xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); inc_nlink(VFS_I(ip)); xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); } int xfs_create( struct user_namespace *mnt_userns, xfs_inode_t *dp, struct xfs_name *name, umode_t mode, dev_t rdev, bool init_xattrs, 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; bool unlock_dp_on_error = false; 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 -EIO; prid = xfs_get_initial_prid(dp); /* * Make sure that we have allocated dquot(s) on disk. */ error = xfs_qm_vop_dqalloc(dp, fsuid_into_mnt(mnt_userns), fsgid_into_mnt(mnt_userns), prid, XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp, &pdqp); if (error) return error; if (is_dir) { resblks = XFS_MKDIR_SPACE_RES(mp, name->len); tres = &M_RES(mp)->tr_mkdir; } else { resblks = XFS_CREATE_SPACE_RES(mp, name->len); tres = &M_RES(mp)->tr_create; } /* * 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. */ error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks, &tp); if (error == -ENOSPC) { /* flush outstanding delalloc blocks and retry */ xfs_flush_inodes(mp); error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks, &tp); } if (error) goto out_release_dquots; xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT); unlock_dp_on_error = true; error = xfs_iext_count_may_overflow(dp, XFS_DATA_FORK, XFS_IEXT_DIR_MANIP_CNT(mp)); 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(mnt_userns, &tp, dp, mode, is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip); if (error) goto out_trans_cancel; /* * 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, resblks - XFS_IALLOC_SPACE_RES(mp)); if (error) { ASSERT(error != -ENOSPC); goto out_trans_cancel; } 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_trans_cancel; xfs_bumplink(tp, dp); } /* * 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_trans_commit(tp); if (error) goto out_release_inode; xfs_qm_dqrele(udqp); xfs_qm_dqrele(gdqp); xfs_qm_dqrele(pdqp); *ipp = ip; return 0; out_trans_cancel: xfs_trans_cancel(tp); out_release_inode: /* * Wait until after the current transaction is aborted to finish the * setup of the inode and release the inode. This prevents recursive * transactions and deadlocks from xfs_inactive. */ if (ip) { xfs_finish_inode_setup(ip); xfs_irele(ip); } out_release_dquots: 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_create_tmpfile( struct user_namespace *mnt_userns, struct xfs_inode *dp, umode_t mode, struct xfs_inode **ipp) { struct xfs_mount *mp = dp->i_mount; struct xfs_inode *ip = NULL; struct xfs_trans *tp = NULL; int error; 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; if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; prid = xfs_get_initial_prid(dp); /* * Make sure that we have allocated dquot(s) on disk. */ error = xfs_qm_vop_dqalloc(dp, fsuid_into_mnt(mnt_userns), fsgid_into_mnt(mnt_userns), prid, XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp, &pdqp); if (error) return error; resblks = XFS_IALLOC_SPACE_RES(mp); tres = &M_RES(mp)->tr_create_tmpfile; error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks, &tp); if (error) goto out_release_dquots; error = xfs_dir_ialloc(mnt_userns, &tp, dp, mode, 0, 0, prid, false, &ip); if (error) goto out_trans_cancel; if (mp->m_flags & XFS_MOUNT_WSYNC) 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_iunlink(tp, ip); if (error) goto out_trans_cancel; error = xfs_trans_commit(tp); if (error) goto out_release_inode; xfs_qm_dqrele(udqp); xfs_qm_dqrele(gdqp); xfs_qm_dqrele(pdqp); *ipp = ip; return 0; out_trans_cancel: xfs_trans_cancel(tp); out_release_inode: /* * Wait until after the current transaction is aborted to finish the * setup of the inode and release the inode. This prevents recursive * transactions and deadlocks from xfs_inactive. */ if (ip) { xfs_finish_inode_setup(ip); xfs_irele(ip); } out_release_dquots: xfs_qm_dqrele(udqp); xfs_qm_dqrele(gdqp); xfs_qm_dqrele(pdqp); 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; int resblks; trace_xfs_link(tdp, target_name); ASSERT(!S_ISDIR(VFS_I(sip)->i_mode)); if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; error = xfs_qm_dqattach(sip); if (error) goto std_return; error = xfs_qm_dqattach(tdp); if (error) goto std_return; resblks = XFS_LINK_SPACE_RES(mp, target_name->len); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp); if (error == -ENOSPC) { resblks = 0; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp); } if (error) goto std_return; xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL); error = xfs_iext_count_may_overflow(tdp, XFS_DATA_FORK, XFS_IEXT_DIR_MANIP_CNT(mp)); if (error) goto error_return; /* * 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) && tdp->i_d.di_projid != sip->i_d.di_projid)) { error = -EXDEV; goto error_return; } if (!resblks) { error = xfs_dir_canenter(tp, tdp, target_name); if (error) goto error_return; } /* * Handle initial link state of O_TMPFILE inode */ if (VFS_I(sip)->i_nlink == 0) { error = xfs_iunlink_remove(tp, sip); if (error) goto error_return; } error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino, resblks); if (error) goto error_return; xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE); xfs_bumplink(tp, sip); /* * 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); return xfs_trans_commit(tp); error_return: xfs_trans_cancel(tp); std_return: return error; } /* Clear the reflink flag and the cowblocks tag if possible. */ static void xfs_itruncate_clear_reflink_flags( struct xfs_inode *ip) { struct xfs_ifork *dfork; struct xfs_ifork *cfork; if (!xfs_is_reflink_inode(ip)) return; dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK); cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK); if (dfork->if_bytes == 0 && cfork->if_bytes == 0) ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK; if (cfork->if_bytes == 0) xfs_inode_clear_cowblocks_tag(ip); } /* * 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_flags( struct xfs_trans **tpp, struct xfs_inode *ip, int whichfork, xfs_fsize_t new_size, int flags) { struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp = *tpp; xfs_fileoff_t first_unmap_block; xfs_filblks_t unmap_len; int error = 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); flags |= xfs_bmapi_aflag(whichfork); /* * 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. * * We have to free all the blocks to the bmbt maximum offset, even if * the page cache can't scale that far. */ first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size); if (!xfs_verify_fileoff(mp, first_unmap_block)) { WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF); return 0; } unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1; while (unmap_len > 0) { ASSERT(tp->t_firstblock == NULLFSBLOCK); error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len, flags, XFS_ITRUNC_MAX_EXTENTS); if (error) goto out; /* free the just unmapped extents */ error = xfs_defer_finish(&tp); if (error) goto out; } if (whichfork == XFS_DATA_FORK) { /* Remove all pending CoW reservations. */ error = xfs_reflink_cancel_cow_blocks(ip, &tp, first_unmap_block, XFS_MAX_FILEOFF, true); if (error) goto out; xfs_itruncate_clear_reflink_flags(ip); } /* * 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; } int xfs_release( xfs_inode_t *ip) { xfs_mount_t *mp = ip->i_mount; int error; if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_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 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 (ip->i_delayed_blks > 0) { error = filemap_flush(VFS_I(ip)->i_mapping); if (error) return error; } } } if (VFS_I(ip)->i_nlink == 0) return 0; if (xfs_can_free_eofblocks(ip, false)) { /* * 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, 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; /* * If we can't get the iolock just skip truncating the blocks * past EOF because we could deadlock with the mmap_lock * 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. */ if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) { error = xfs_free_eofblocks(ip); xfs_iunlock(ip, XFS_IOLOCK_EXCL); if (error) 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_truncate * * Called to perform a truncate when an inode becomes unlinked. */ STATIC int xfs_inactive_truncate( struct xfs_inode *ip) { struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; int error; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); if (error) { ASSERT(XFS_FORCED_SHUTDOWN(mp)); return error; } xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); /* * Log the inode size first to prevent stale data exposure in the event * of a system crash before the truncate completes. See the related * comment in xfs_vn_setattr_size() for details. */ 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 error_trans_cancel; ASSERT(ip->i_df.if_nextents == 0); error = xfs_trans_commit(tp); if (error) goto error_unlock; xfs_iunlock(ip, XFS_ILOCK_EXCL); return 0; error_trans_cancel: xfs_trans_cancel(tp); error_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); return error; } /* * xfs_inactive_ifree() * * Perform the inode free when an inode is unlinked. */ STATIC int xfs_inactive_ifree( struct xfs_inode *ip) { struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; int error; /* * We try to use a per-AG reservation for any block needed by the finobt * tree, but as the finobt feature predates the per-AG reservation * support a degraded file system might not have enough space for the * reservation at mount time. In that case try to dip into the reserved * pool and pray. * * Send a warning if the reservation does happen to fail, as the inode * now remains allocated and sits on the unlinked list until the fs is * repaired. */ if (unlikely(mp->m_finobt_nores)) { error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp); } else { error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp); } if (error) { if (error == -ENOSPC) { xfs_warn_ratelimited(mp, "Failed to remove inode(s) from unlinked list. " "Please free space, unmount and run xfs_repair."); } else { ASSERT(XFS_FORCED_SHUTDOWN(mp)); } return error; } /* * We do not hold the inode locked across the entire rolling transaction * here. We only need to hold it for the first transaction that * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode * here breaks the relationship between cluster buffer invalidation and * stale inode invalidation on cluster buffer item journal commit * completion, and can result in leaving dirty stale inodes hanging * around in memory. * * We have no need for serialising this inode operation against other * operations - we freed the inode and hence reallocation is required * and that will serialise on reallocating the space the deferops need * to free. Hence we can unlock the inode on the first commit of * the transaction rather than roll it right through the deferops. This * avoids relogging the XFS_ISTALE inode. * * We check that xfs_ifree() hasn't grown an internal transaction roll * by asserting that the inode is still locked when it returns. */ xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); error = xfs_ifree(tp, ip); ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); 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); return error; } /* * 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_trans_commit(tp); if (error) xfs_notice(mp, "%s: xfs_trans_commit returned error %d", __func__, error); 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. */ void xfs_inactive( xfs_inode_t *ip) { struct xfs_mount *mp; int error; int truncate = 0; /* * If the inode is already free, then there can be nothing * to clean up here. */ if (VFS_I(ip)->i_mode == 0) { ASSERT(ip->i_df.if_broot_bytes == 0); return; } mp = ip->i_mount; ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY)); /* If this is a read-only mount, don't do this (would generate I/O) */ if (mp->m_flags & XFS_MOUNT_RDONLY) return; /* Metadata inodes require explicit resource cleanup. */ if (xfs_is_metadata_inode(ip)) return; /* Try to clean out the cow blocks if there are any. */ if (xfs_inode_has_cow_data(ip)) xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true); if (VFS_I(ip)->i_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. * * Note: don't bother with iolock here since lockdep complains * about acquiring it in reclaim context. We have the only * reference to the inode at this point anyways. */ if (xfs_can_free_eofblocks(ip, true)) xfs_free_eofblocks(ip); return; } if (S_ISREG(VFS_I(ip)->i_mode) && (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 || ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0)) truncate = 1; error = xfs_qm_dqattach(ip); if (error) return; if (S_ISLNK(VFS_I(ip)->i_mode)) error = xfs_inactive_symlink(ip); else if (truncate) error = xfs_inactive_truncate(ip); if (error) return; /* * If there are attributes associated with the file then blow them away * now. The code calls a routine that recursively deconstructs the * attribute fork. If also blows away the in-core attribute fork. */ if (XFS_IFORK_Q(ip)) { error = xfs_attr_inactive(ip); if (error) return; } ASSERT(!ip->i_afp); ASSERT(ip->i_d.di_forkoff == 0); /* * Free the inode. */ error = xfs_inactive_ifree(ip); if (error) return; /* * Release the dquots held by inode, if any. */ xfs_qm_dqdetach(ip); } /* * In-Core Unlinked List Lookups * ============================= * * Every inode is supposed to be reachable from some other piece of metadata * with the exception of the root directory. Inodes with a connection to a * file descriptor but not linked from anywhere in the on-disk directory tree * are collectively known as unlinked inodes, though the filesystem itself * maintains links to these inodes so that on-disk metadata are consistent. * * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI * header contains a number of buckets that point to an inode, and each inode * record has a pointer to the next inode in the hash chain. This * singly-linked list causes scaling problems in the iunlink remove function * because we must walk that list to find the inode that points to the inode * being removed from the unlinked hash bucket list. * * What if we modelled the unlinked list as a collection of records capturing * "X.next_unlinked = Y" relations? If we indexed those records on Y, we'd * have a fast way to look up unlinked list predecessors, which avoids the * slow list walk. That's exactly what we do here (in-core) with a per-AG * rhashtable. * * Because this is a backref cache, we ignore operational failures since the * iunlink code can fall back to the slow bucket walk. The only errors that * should bubble out are for obviously incorrect situations. * * All users of the backref cache MUST hold the AGI buffer lock to serialize * access or have otherwise provided for concurrency control. */ /* Capture a "X.next_unlinked = Y" relationship. */ struct xfs_iunlink { struct rhash_head iu_rhash_head; xfs_agino_t iu_agino; /* X */ xfs_agino_t iu_next_unlinked; /* Y */ }; /* Unlinked list predecessor lookup hashtable construction */ static int xfs_iunlink_obj_cmpfn( struct rhashtable_compare_arg *arg, const void *obj) { const xfs_agino_t *key = arg->key; const struct xfs_iunlink *iu = obj; if (iu->iu_next_unlinked != *key) return 1; return 0; } static const struct rhashtable_params xfs_iunlink_hash_params = { .min_size = XFS_AGI_UNLINKED_BUCKETS, .key_len = sizeof(xfs_agino_t), .key_offset = offsetof(struct xfs_iunlink, iu_next_unlinked), .head_offset = offsetof(struct xfs_iunlink, iu_rhash_head), .automatic_shrinking = true, .obj_cmpfn = xfs_iunlink_obj_cmpfn, }; /* * Return X, where X.next_unlinked == @agino. Returns NULLAGINO if no such * relation is found. */ static xfs_agino_t xfs_iunlink_lookup_backref( struct xfs_perag *pag, xfs_agino_t agino) { struct xfs_iunlink *iu; iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino, xfs_iunlink_hash_params); return iu ? iu->iu_agino : NULLAGINO; } /* * Take ownership of an iunlink cache entry and insert it into the hash table. * If successful, the entry will be owned by the cache; if not, it is freed. * Either way, the caller does not own @iu after this call. */ static int xfs_iunlink_insert_backref( struct xfs_perag *pag, struct xfs_iunlink *iu) { int error; error = rhashtable_insert_fast(&pag->pagi_unlinked_hash, &iu->iu_rhash_head, xfs_iunlink_hash_params); /* * Fail loudly if there already was an entry because that's a sign of * corruption of in-memory data. Also fail loudly if we see an error * code we didn't anticipate from the rhashtable code. Currently we * only anticipate ENOMEM. */ if (error) { WARN(error != -ENOMEM, "iunlink cache insert error %d", error); kmem_free(iu); } /* * Absorb any runtime errors that aren't a result of corruption because * this is a cache and we can always fall back to bucket list scanning. */ if (error != 0 && error != -EEXIST) error = 0; return error; } /* Remember that @prev_agino.next_unlinked = @this_agino. */ static int xfs_iunlink_add_backref( struct xfs_perag *pag, xfs_agino_t prev_agino, xfs_agino_t this_agino) { struct xfs_iunlink *iu; if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK)) return 0; iu = kmem_zalloc(sizeof(*iu), KM_NOFS); iu->iu_agino = prev_agino; iu->iu_next_unlinked = this_agino; return xfs_iunlink_insert_backref(pag, iu); } /* * Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked. * If @next_unlinked is NULLAGINO, we drop the backref and exit. If there * wasn't any such entry then we don't bother. */ static int xfs_iunlink_change_backref( struct xfs_perag *pag, xfs_agino_t agino, xfs_agino_t next_unlinked) { struct xfs_iunlink *iu; int error; /* Look up the old entry; if there wasn't one then exit. */ iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino, xfs_iunlink_hash_params); if (!iu) return 0; /* * Remove the entry. This shouldn't ever return an error, but if we * couldn't remove the old entry we don't want to add it again to the * hash table, and if the entry disappeared on us then someone's * violated the locking rules and we need to fail loudly. Either way * we cannot remove the inode because internal state is or would have * been corrupt. */ error = rhashtable_remove_fast(&pag->pagi_unlinked_hash, &iu->iu_rhash_head, xfs_iunlink_hash_params); if (error) return error; /* If there is no new next entry just free our item and return. */ if (next_unlinked == NULLAGINO) { kmem_free(iu); return 0; } /* Update the entry and re-add it to the hash table. */ iu->iu_next_unlinked = next_unlinked; return xfs_iunlink_insert_backref(pag, iu); } /* Set up the in-core predecessor structures. */ int xfs_iunlink_init( struct xfs_perag *pag) { return rhashtable_init(&pag->pagi_unlinked_hash, &xfs_iunlink_hash_params); } /* Free the in-core predecessor structures. */ static void xfs_iunlink_free_item( void *ptr, void *arg) { struct xfs_iunlink *iu = ptr; bool *freed_anything = arg; *freed_anything = true; kmem_free(iu); } void xfs_iunlink_destroy( struct xfs_perag *pag) { bool freed_anything = false; rhashtable_free_and_destroy(&pag->pagi_unlinked_hash, xfs_iunlink_free_item, &freed_anything); ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount)); } /* * Point the AGI unlinked bucket at an inode and log the results. The caller * is responsible for validating the old value. */ STATIC int xfs_iunlink_update_bucket( struct xfs_trans *tp, xfs_agnumber_t agno, struct xfs_buf *agibp, unsigned int bucket_index, xfs_agino_t new_agino) { struct xfs_agi *agi = agibp->b_addr; xfs_agino_t old_value; int offset; ASSERT(xfs_verify_agino_or_null(tp->t_mountp, agno, new_agino)); old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]); trace_xfs_iunlink_update_bucket(tp->t_mountp, agno, bucket_index, old_value, new_agino); /* * We should never find the head of the list already set to the value * passed in because either we're adding or removing ourselves from the * head of the list. */ if (old_value == new_agino) { xfs_buf_mark_corrupt(agibp); return -EFSCORRUPTED; } agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino); offset = offsetof(struct xfs_agi, agi_unlinked) + (sizeof(xfs_agino_t) * bucket_index); xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1); return 0; } /* Set an on-disk inode's next_unlinked pointer. */ STATIC void xfs_iunlink_update_dinode( struct xfs_trans *tp, xfs_agnumber_t agno, xfs_agino_t agino, struct xfs_buf *ibp, struct xfs_dinode *dip, struct xfs_imap *imap, xfs_agino_t next_agino) { struct xfs_mount *mp = tp->t_mountp; int offset; ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino)); trace_xfs_iunlink_update_dinode(mp, agno, agino, be32_to_cpu(dip->di_next_unlinked), next_agino); dip->di_next_unlinked = cpu_to_be32(next_agino); offset = imap->im_boffset + offsetof(struct xfs_dinode, 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); } /* Set an in-core inode's unlinked pointer and return the old value. */ STATIC int xfs_iunlink_update_inode( struct xfs_trans *tp, struct xfs_inode *ip, xfs_agnumber_t agno, xfs_agino_t next_agino, xfs_agino_t *old_next_agino) { struct xfs_mount *mp = tp->t_mountp; struct xfs_dinode *dip; struct xfs_buf *ibp; xfs_agino_t old_value; int error; ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino)); error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0); if (error) return error; /* Make sure the old pointer isn't garbage. */ old_value = be32_to_cpu(dip->di_next_unlinked); if (!xfs_verify_agino_or_null(mp, agno, old_value)) { xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip, sizeof(*dip), __this_address); error = -EFSCORRUPTED; goto out; } /* * Since we're updating a linked list, we should never find that the * current pointer is the same as the new value, unless we're * terminating the list. */ *old_next_agino = old_value; if (old_value == next_agino) { if (next_agino != NULLAGINO) { xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip, sizeof(*dip), __this_address); error = -EFSCORRUPTED; } goto out; } /* Ok, update the new pointer. */ xfs_iunlink_update_dinode(tp, agno, XFS_INO_TO_AGINO(mp, ip->i_ino), ibp, dip, &ip->i_imap, next_agino); return 0; out: xfs_trans_brelse(tp, ibp); return error; } /* * This is called when the inode's link count has gone to 0 or we are creating * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 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. */ STATIC int xfs_iunlink( struct xfs_trans *tp, struct xfs_inode *ip) { struct xfs_mount *mp = tp->t_mountp; struct xfs_agi *agi; struct xfs_buf *agibp; xfs_agino_t next_agino; xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino); xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino); short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; int error; ASSERT(VFS_I(ip)->i_nlink == 0); ASSERT(VFS_I(ip)->i_mode != 0); trace_xfs_iunlink(ip); /* 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 = agibp->b_addr; /* * Get the index into the agi hash table for the list this inode will * go on. Make sure the pointer isn't garbage and that this inode * isn't already on the list. */ next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]); if (next_agino == agino || !xfs_verify_agino_or_null(mp, agno, next_agino)) { xfs_buf_mark_corrupt(agibp); return -EFSCORRUPTED; } if (next_agino != NULLAGINO) { xfs_agino_t old_agino; /* * There is already another inode in the bucket, so point this * inode to the current head of the list. */ error = xfs_iunlink_update_inode(tp, ip, agno, next_agino, &old_agino); if (error) return error; ASSERT(old_agino == NULLAGINO); /* * agino has been unlinked, add a backref from the next inode * back to agino. */ error = xfs_iunlink_add_backref(agibp->b_pag, agino, next_agino); if (error) return error; } /* Point the head of the list to point to this inode. */ return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index, agino); } /* Return the imap, dinode pointer, and buffer for an inode. */ STATIC int xfs_iunlink_map_ino( struct xfs_trans *tp, xfs_agnumber_t agno, xfs_agino_t agino, struct xfs_imap *imap, struct xfs_dinode **dipp, struct xfs_buf **bpp) { struct xfs_mount *mp = tp->t_mountp; int error; imap->im_blkno = 0; error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), 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, dipp, bpp, 0); if (error) { xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.", __func__, error); return error; } return 0; } /* * Walk the unlinked chain from @head_agino until we find the inode that * points to @target_agino. Return the inode number, map, dinode pointer, * and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp. * * @tp, @pag, @head_agino, and @target_agino are input parameters. * @agino, @imap, @dipp, and @bpp are all output parameters. * * Do not call this function if @target_agino is the head of the list. */ STATIC int xfs_iunlink_map_prev( struct xfs_trans *tp, xfs_agnumber_t agno, xfs_agino_t head_agino, xfs_agino_t target_agino, xfs_agino_t *agino, struct xfs_imap *imap, struct xfs_dinode **dipp, struct xfs_buf **bpp, struct xfs_perag *pag) { struct xfs_mount *mp = tp->t_mountp; xfs_agino_t next_agino; int error; ASSERT(head_agino != target_agino); *bpp = NULL; /* See if our backref cache can find it faster. */ *agino = xfs_iunlink_lookup_backref(pag, target_agino); if (*agino != NULLAGINO) { error = xfs_iunlink_map_ino(tp, agno, *agino, imap, dipp, bpp); if (error) return error; if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino) return 0; /* * If we get here the cache contents were corrupt, so drop the * buffer and fall back to walking the bucket list. */ xfs_trans_brelse(tp, *bpp); *bpp = NULL; WARN_ON_ONCE(1); } trace_xfs_iunlink_map_prev_fallback(mp, agno); /* Otherwise, walk the entire bucket until we find it. */ next_agino = head_agino; while (next_agino != target_agino) { xfs_agino_t unlinked_agino; if (*bpp) xfs_trans_brelse(tp, *bpp); *agino = next_agino; error = xfs_iunlink_map_ino(tp, agno, next_agino, imap, dipp, bpp); if (error) return error; unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked); /* * Make sure this pointer is valid and isn't an obvious * infinite loop. */ if (!xfs_verify_agino(mp, agno, unlinked_agino) || next_agino == unlinked_agino) { XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, *dipp, sizeof(**dipp)); error = -EFSCORRUPTED; return error; } next_agino = unlinked_agino; } return 0; } /* * Pull the on-disk inode from the AGI unlinked list. */ STATIC int xfs_iunlink_remove( struct xfs_trans *tp, struct xfs_inode *ip) { struct xfs_mount *mp = tp->t_mountp; struct xfs_agi *agi; struct xfs_buf *agibp; struct xfs_buf *last_ibp; struct xfs_dinode *last_dip = NULL; xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino); xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino); xfs_agino_t next_agino; xfs_agino_t head_agino; short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; int error; trace_xfs_iunlink_remove(ip); /* 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 = agibp->b_addr; /* * Get the index into the agi hash table for the list this inode will * go on. Make sure the head pointer isn't garbage. */ head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]); if (!xfs_verify_agino(mp, agno, head_agino)) { XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, agi, sizeof(*agi)); return -EFSCORRUPTED; } /* * Set our inode's next_unlinked pointer to NULL and then return * the old pointer value so that we can update whatever was previous * to us in the list to point to whatever was next in the list. */ error = xfs_iunlink_update_inode(tp, ip, agno, NULLAGINO, &next_agino); if (error) return error; /* * If there was a backref pointing from the next inode back to this * one, remove it because we've removed this inode from the list. * * Later, if this inode was in the middle of the list we'll update * this inode's backref to point from the next inode. */ if (next_agino != NULLAGINO) { error = xfs_iunlink_change_backref(agibp->b_pag, next_agino, NULLAGINO); if (error) return error; } if (head_agino != agino) { struct xfs_imap imap; xfs_agino_t prev_agino; /* We need to search the list for the inode being freed. */ error = xfs_iunlink_map_prev(tp, agno, head_agino, agino, &prev_agino, &imap, &last_dip, &last_ibp, agibp->b_pag); if (error) return error; /* Point the previous inode on the list to the next inode. */ xfs_iunlink_update_dinode(tp, agno, prev_agino, last_ibp, last_dip, &imap, next_agino); /* * Now we deal with the backref for this inode. If this inode * pointed at a real inode, change the backref that pointed to * us to point to our old next. If this inode was the end of * the list, delete the backref that pointed to us. Note that * change_backref takes care of deleting the backref if * next_agino is NULLAGINO. */ return xfs_iunlink_change_backref(agibp->b_pag, agino, next_agino); } /* Point the head of the list to the next unlinked inode. */ return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index, next_agino); } /* * Look up the inode number specified and if it is not already marked XFS_ISTALE * mark it stale. We should only find clean inodes in this lookup that aren't * already stale. */ static void xfs_ifree_mark_inode_stale( struct xfs_buf *bp, struct xfs_inode *free_ip, xfs_ino_t inum) { struct xfs_mount *mp = bp->b_mount; struct xfs_perag *pag = bp->b_pag; struct xfs_inode_log_item *iip; struct xfs_inode *ip; retry: rcu_read_lock(); ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum)); /* Inode not in memory, nothing to do */ if (!ip) { rcu_read_unlock(); return; } /* * 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 || __xfs_iflags_test(ip, XFS_ISTALE)) goto out_iflags_unlock; /* * 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) { if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) { spin_unlock(&ip->i_flags_lock); rcu_read_unlock(); delay(1); goto retry; } } ip->i_flags |= XFS_ISTALE; /* * If the inode is flushing, it is already attached to the buffer. All * we needed to do here is mark the inode stale so buffer IO completion * will remove it from the AIL. */ iip = ip->i_itemp; if (__xfs_iflags_test(ip, XFS_IFLUSHING)) { ASSERT(!list_empty(&iip->ili_item.li_bio_list)); ASSERT(iip->ili_last_fields); goto out_iunlock; } /* * Inodes not attached to the buffer can be released immediately. * Everything else has to go through xfs_iflush_abort() on journal * commit as the flock synchronises removal of the inode from the * cluster buffer against inode reclaim. */ if (!iip || list_empty(&iip->ili_item.li_bio_list)) goto out_iunlock; __xfs_iflags_set(ip, XFS_IFLUSHING); spin_unlock(&ip->i_flags_lock); rcu_read_unlock(); /* we have a dirty inode in memory that has not yet been flushed. */ spin_lock(&iip->ili_lock); iip->ili_last_fields = iip->ili_fields; iip->ili_fields = 0; iip->ili_fsync_fields = 0; spin_unlock(&iip->ili_lock); ASSERT(iip->ili_last_fields); if (ip != free_ip) xfs_iunlock(ip, XFS_ILOCK_EXCL); return; out_iunlock: if (ip != free_ip) xfs_iunlock(ip, XFS_ILOCK_EXCL); out_iflags_unlock: spin_unlock(&ip->i_flags_lock); rcu_read_unlock(); } /* * A big issue when freeing the inode cluster 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( struct xfs_inode *free_ip, struct xfs_trans *tp, struct xfs_icluster *xic) { struct xfs_mount *mp = free_ip->i_mount; struct xfs_ino_geometry *igeo = M_IGEO(mp); struct xfs_buf *bp; xfs_daddr_t blkno; xfs_ino_t inum = xic->first_ino; int nbufs; int i, j; int ioffset; int error; nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster; for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) { /* * The allocation bitmap tells us which inodes of the chunk were * physically allocated. Skip the cluster if an inode falls into * a sparse region. */ ioffset = inum - xic->first_ino; if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) { ASSERT(ioffset % igeo->inodes_per_cluster == 0); continue; } 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 to ensure dirty inodes attached to the buffer remain in * the flushing state while we mark them stale. * * 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. */ error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno, mp->m_bsize * igeo->blocks_per_cluster, XBF_UNMAPPED, &bp); if (error) return error; /* * 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; /* * Now we need to set all the cached clean inodes as XFS_ISTALE, * too. This requires lookups, and will skip inodes that we've * already marked XFS_ISTALE. */ for (i = 0; i < igeo->inodes_per_cluster; i++) xfs_ifree_mark_inode_stale(bp, free_ip, inum + i); xfs_trans_stale_inode_buf(tp, bp); xfs_trans_binval(tp, bp); } 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( struct xfs_trans *tp, struct xfs_inode *ip) { int error; struct xfs_icluster xic = { 0 }; struct xfs_inode_log_item *iip = ip->i_itemp; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); ASSERT(VFS_I(ip)->i_nlink == 0); ASSERT(ip->i_df.if_nextents == 0); ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_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, &xic); if (error) return error; /* * Free any local-format data sitting around before we reset the * data fork to extents format. Note that the attr fork data has * already been freed by xfs_attr_inactive. */ if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) { kmem_free(ip->i_df.if_u1.if_data); ip->i_df.if_u1.if_data = NULL; ip->i_df.if_bytes = 0; } VFS_I(ip)->i_mode = 0; /* mark incore inode as free */ ip->i_d.di_flags = 0; ip->i_d.di_flags2 = ip->i_mount->m_ino_geo.new_diflags2; ip->i_d.di_dmevmask = 0; ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */ ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS; /* Don't attempt to replay owner changes for a deleted inode */ spin_lock(&iip->ili_lock); iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER); spin_unlock(&iip->ili_lock); /* * Bump the generation count so no one will be confused * by reincarnations of this inode. */ VFS_I(ip)->i_generation++; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); if (xic.deleted) error = xfs_ifree_cluster(ip, tp, &xic); 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, NULL); } 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.wq_entry, TASK_UNINTERRUPTIBLE); if (xfs_ipincount(ip)) io_schedule(); } while (xfs_ipincount(ip)); finish_wait(wq, &wait.wq_entry); } void xfs_iunpin_wait( struct xfs_inode *ip) { if (xfs_ipincount(ip)) __xfs_iunpin_wait(ip); } /* * Removing an inode from the namespace involves removing the directory entry * and dropping the link count on the inode. Removing the directory entry can * result in locking an AGF (directory blocks were freed) and removing a link * count can result in placing the inode on an unlinked list which results in * locking an AGI. * * The big problem here is that we have an ordering constraint on AGF and AGI * locking - inode allocation locks the AGI, then can allocate a new extent for * new inodes, locking the AGF after the AGI. Similarly, freeing the inode * removes the inode from the unlinked list, requiring that we lock the AGI * first, and then freeing the inode can result in an inode chunk being freed * and hence freeing disk space requiring that we lock an AGF. * * Hence the ordering that is imposed by other parts of the code is AGI before * AGF. This means we cannot remove the directory entry before we drop the inode * reference count and put it on the unlinked list as this results in a lock * order of AGF then AGI, and this can deadlock against inode allocation and * freeing. Therefore we must drop the link counts before we remove the * directory entry. * * This is still safe from a transactional point of view - it is not until we * get to xfs_defer_finish() that we have the possibility of multiple * transactions in this operation. Hence as long as we remove the directory * entry and drop the link count in the first transaction of the remove * operation, there are no transactional constraints on the ordering here. */ 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(VFS_I(ip)->i_mode); int error = 0; uint resblks; trace_xfs_remove(dp, name); if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; error = xfs_qm_dqattach(dp); if (error) goto std_return; error = xfs_qm_dqattach(ip); if (error) goto std_return; /* * 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_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp); if (error == -ENOSPC) { resblks = 0; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0, &tp); } if (error) { ASSERT(error != -ENOSPC); goto std_return; } xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, 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(VFS_I(ip)->i_nlink >= 2); if (VFS_I(ip)->i_nlink != 2) { error = -ENOTEMPTY; goto out_trans_cancel; } if (!xfs_dir_isempty(ip)) { error = -ENOTEMPTY; goto out_trans_cancel; } /* Drop the link from ip's "..". */ error = xfs_droplink(tp, dp); if (error) goto out_trans_cancel; /* Drop the "." link from ip to self. */ error = xfs_droplink(tp, ip); if (error) goto out_trans_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); } xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); /* Drop the link from dp to ip. */ error = xfs_droplink(tp, ip); if (error) goto out_trans_cancel; error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks); if (error) { ASSERT(error != -ENOENT); goto out_trans_cancel; } /* * 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_trans_commit(tp); if (error) goto std_return; if (is_dir && xfs_inode_is_filestream(ip)) xfs_filestream_deassociate(ip); return 0; out_trans_cancel: xfs_trans_cancel(tp); std_return: return error; } /* * Enter all inodes for a rename transaction into a sorted array. */ #define __XFS_SORT_INODES 5 STATIC void xfs_sort_for_rename( struct xfs_inode *dp1, /* in: old (source) directory inode */ struct xfs_inode *dp2, /* in: new (target) directory inode */ struct xfs_inode *ip1, /* in: inode of old entry */ struct xfs_inode *ip2, /* in: inode of new entry */ struct xfs_inode *wip, /* in: whiteout inode */ struct xfs_inode **i_tab,/* out: sorted array of inodes */ int *num_inodes) /* in/out: inodes in array */ { int i, j; ASSERT(*num_inodes == __XFS_SORT_INODES); memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *)); /* * 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 = 0; i_tab[i++] = dp1; i_tab[i++] = dp2; i_tab[i++] = ip1; if (ip2) i_tab[i++] = ip2; if (wip) i_tab[i++] = wip; *num_inodes = i; /* * Sort the elements via bubble sort. (Remember, there are at * most 5 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) { struct xfs_inode *temp = i_tab[j]; i_tab[j] = i_tab[j-1]; i_tab[j-1] = temp; } } } } static int xfs_finish_rename( struct xfs_trans *tp) { /* * If this is a synchronous mount, make sure that the rename transaction * goes to disk before returning to the user. */ if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) xfs_trans_set_sync(tp); return xfs_trans_commit(tp); } /* * xfs_cross_rename() * * responsible for handling RENAME_EXCHANGE flag in renameat2() syscall */ STATIC int xfs_cross_rename( struct xfs_trans *tp, struct xfs_inode *dp1, struct xfs_name *name1, struct xfs_inode *ip1, struct xfs_inode *dp2, struct xfs_name *name2, struct xfs_inode *ip2, int spaceres) { int error = 0; int ip1_flags = 0; int ip2_flags = 0; int dp2_flags = 0; /* Swap inode number for dirent in first parent */ error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres); if (error) goto out_trans_abort; /* Swap inode number for dirent in second parent */ error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres); if (error) goto out_trans_abort; /* * If we're renaming one or more directories across different parents, * update the respective ".." entries (and link counts) to match the new * parents. */ if (dp1 != dp2) { dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG; if (S_ISDIR(VFS_I(ip2)->i_mode)) { error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot, dp1->i_ino, spaceres); if (error) goto out_trans_abort; /* transfer ip2 ".." reference to dp1 */ if (!S_ISDIR(VFS_I(ip1)->i_mode)) { error = xfs_droplink(tp, dp2); if (error) goto out_trans_abort; xfs_bumplink(tp, dp1); } /* * Although ip1 isn't changed here, userspace needs * to be warned about the change, so that applications * relying on it (like backup ones), will properly * notify the change */ ip1_flags |= XFS_ICHGTIME_CHG; ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG; } if (S_ISDIR(VFS_I(ip1)->i_mode)) { error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot, dp2->i_ino, spaceres); if (error) goto out_trans_abort; /* transfer ip1 ".." reference to dp2 */ if (!S_ISDIR(VFS_I(ip2)->i_mode)) { error = xfs_droplink(tp, dp1); if (error) goto out_trans_abort; xfs_bumplink(tp, dp2); } /* * Although ip2 isn't changed here, userspace needs * to be warned about the change, so that applications * relying on it (like backup ones), will properly * notify the change */ ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG; ip2_flags |= XFS_ICHGTIME_CHG; } } if (ip1_flags) { xfs_trans_ichgtime(tp, ip1, ip1_flags); xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE); } if (ip2_flags) { xfs_trans_ichgtime(tp, ip2, ip2_flags); xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE); } if (dp2_flags) { xfs_trans_ichgtime(tp, dp2, dp2_flags); xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE); } xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE); return xfs_finish_rename(tp); out_trans_abort: xfs_trans_cancel(tp); return error; } /* * xfs_rename_alloc_whiteout() * * Return a referenced, unlinked, unlocked inode that can be used as a * whiteout in a rename transaction. We use a tmpfile inode here so that if we * crash between allocating the inode and linking it into the rename transaction * recovery will free the inode and we won't leak it. */ static int xfs_rename_alloc_whiteout( struct user_namespace *mnt_userns, struct xfs_inode *dp, struct xfs_inode **wip) { struct xfs_inode *tmpfile; int error; error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE, &tmpfile); if (error) return error; /* * Prepare the tmpfile inode as if it were created through the VFS. * Complete the inode setup and flag it as linkable. nlink is already * zero, so we can skip the drop_nlink. */ xfs_setup_iops(tmpfile); xfs_finish_inode_setup(tmpfile); VFS_I(tmpfile)->i_state |= I_LINKABLE; *wip = tmpfile; return 0; } /* * xfs_rename */ int xfs_rename( struct user_namespace *mnt_userns, struct xfs_inode *src_dp, struct xfs_name *src_name, struct xfs_inode *src_ip, struct xfs_inode *target_dp, struct xfs_name *target_name, struct xfs_inode *target_ip, unsigned int flags) { struct xfs_mount *mp = src_dp->i_mount; struct xfs_trans *tp; struct xfs_inode *wip = NULL; /* whiteout inode */ struct xfs_inode *inodes[__XFS_SORT_INODES]; int i; int num_inodes = __XFS_SORT_INODES; bool new_parent = (src_dp != target_dp); bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode); int spaceres; int error; trace_xfs_rename(src_dp, target_dp, src_name, target_name); if ((flags & RENAME_EXCHANGE) && !target_ip) return -EINVAL; /* * If we are doing a whiteout operation, allocate the whiteout inode * we will be placing at the target and ensure the type is set * appropriately. */ if (flags & RENAME_WHITEOUT) { ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE))); error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip); if (error) return error; /* setup target dirent info as whiteout */ src_name->type = XFS_DIR3_FT_CHRDEV; } xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip, inodes, &num_inodes); spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp); if (error == -ENOSPC) { spaceres = 0; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0, &tp); } if (error) goto out_release_wip; /* * Attach the dquots to the inodes */ error = xfs_qm_vop_rename_dqattach(inodes); if (error) goto out_trans_cancel; /* * 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 (wip) xfs_trans_ijoin(tp, wip, 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) && target_dp->i_d.di_projid != src_ip->i_d.di_projid)) { error = -EXDEV; goto out_trans_cancel; } /* RENAME_EXCHANGE is unique from here on. */ if (flags & RENAME_EXCHANGE) return xfs_cross_rename(tp, src_dp, src_name, src_ip, target_dp, target_name, target_ip, spaceres); /* * Check for expected errors before we dirty the transaction * so we can return an error without a transaction abort. * * Extent count overflow check: * * From the perspective of src_dp, a rename operation is essentially a * directory entry remove operation. Hence the only place where we check * for extent count overflow for src_dp is in * xfs_bmap_del_extent_real(). xfs_bmap_del_extent_real() returns * -ENOSPC when it detects a possible extent count overflow and in * response, the higher layers of directory handling code do the * following: * 1. Data/Free blocks: XFS lets these blocks linger until a * future remove operation removes them. * 2. Dabtree blocks: XFS swaps the blocks with the last block in the * Leaf space and unmaps the last block. * * For target_dp, there are two cases depending on whether the * destination directory entry exists or not. * * When destination directory entry does not exist (i.e. target_ip == * NULL), extent count overflow check is performed only when transaction * has a non-zero sized space reservation associated with it. With a * zero-sized space reservation, XFS allows a rename operation to * continue only when the directory has sufficient free space in its * data/leaf/free space blocks to hold the new entry. * * When destination directory entry exists (i.e. target_ip != NULL), all * we need to do is change the inode number associated with the already * existing entry. Hence there is no need to perform an extent count * overflow check. */ if (target_ip == NULL) { /* * If there's no space reservation, check the entry will * fit before actually inserting it. */ if (!spaceres) { error = xfs_dir_canenter(tp, target_dp, target_name); if (error) goto out_trans_cancel; } else { error = xfs_iext_count_may_overflow(target_dp, XFS_DATA_FORK, XFS_IEXT_DIR_MANIP_CNT(mp)); if (error) goto out_trans_cancel; } } else { /* * If target exists and it's a directory, check that whether * it can be destroyed. */ if (S_ISDIR(VFS_I(target_ip)->i_mode) && (!xfs_dir_isempty(target_ip) || (VFS_I(target_ip)->i_nlink > 2))) { error = -EEXIST; goto out_trans_cancel; } } /* * Lock the AGI buffers we need to handle bumping the nlink of the * whiteout inode off the unlinked list and to handle dropping the * nlink of the target inode. Per locking order rules, do this in * increasing AG order and before directory block allocation tries to * grab AGFs because we grab AGIs before AGFs. * * The (vfs) caller must ensure that if src is a directory then * target_ip is either null or an empty directory. */ for (i = 0; i < num_inodes && inodes[i] != NULL; i++) { if (inodes[i] == wip || (inodes[i] == target_ip && (VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) { struct xfs_buf *bp; xfs_agnumber_t agno; agno = XFS_INO_TO_AGNO(mp, inodes[i]->i_ino); error = xfs_read_agi(mp, tp, agno, &bp); if (error) goto out_trans_cancel; } } /* * Directory entry creation below may acquire the AGF. Remove * the whiteout from the unlinked list first to preserve correct * AGI/AGF locking order. This dirties the transaction so failures * after this point will abort and log recovery will clean up the * mess. * * For whiteouts, we need to bump the link count on the whiteout * inode. After this point, we have a real link, clear the tmpfile * state flag from the inode so it doesn't accidentally get misused * in future. */ if (wip) { ASSERT(VFS_I(wip)->i_nlink == 0); error = xfs_iunlink_remove(tp, wip); if (error) goto out_trans_cancel; xfs_bumplink(tp, wip); VFS_I(wip)->i_state &= ~I_LINKABLE; } /* * Set up the target. */ if (target_ip == NULL) { /* * 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, spaceres); if (error) goto out_trans_cancel; xfs_trans_ichgtime(tp, target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); if (new_parent && src_is_directory) { xfs_bumplink(tp, target_dp); } } else { /* target_ip != NULL */ /* * 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, spaceres); if (error) goto out_trans_cancel; 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 out_trans_cancel; if (src_is_directory) { /* * Drop the link from the old "." entry. */ error = xfs_droplink(tp, target_ip); if (error) goto out_trans_cancel; } } /* 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, spaceres); ASSERT(error != -EEXIST); if (error) goto out_trans_cancel; } /* * 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 out_trans_cancel; } /* * For whiteouts, we only need to update the source dirent with the * inode number of the whiteout inode rather than removing it * altogether. */ if (wip) { error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino, spaceres); } else { /* * NOTE: We don't need to check for extent count overflow here * because the dir remove name code will leave the dir block in * place if the extent count would overflow. */ error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino, spaceres); } if (error) goto out_trans_cancel; 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); error = xfs_finish_rename(tp); if (wip) xfs_irele(wip); return error; out_trans_cancel: xfs_trans_cancel(tp); out_release_wip: if (wip) xfs_irele(wip); return error; } static int xfs_iflush( 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; int error; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING)); ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE || ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)); ASSERT(iip->ili_item.li_buf == bp); dip = xfs_buf_offset(bp, ip->i_imap.im_boffset); /* * We don't flush the inode if any of the following checks fail, but we * do still update the log item and attach to the backing buffer as if * the flush happened. This is a formality to facilitate predictable * error handling as the caller will shutdown and fail the buffer. */ error = -EFSCORRUPTED; if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC), mp, XFS_ERRTAG_IFLUSH_1)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT, __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip); goto flush_out; } if (S_ISREG(VFS_I(ip)->i_mode)) { if (XFS_TEST_ERROR( ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS && ip->i_df.if_format != XFS_DINODE_FMT_BTREE, mp, XFS_ERRTAG_IFLUSH_3)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad regular inode %Lu, ptr "PTR_FMT, __func__, ip->i_ino, ip); goto flush_out; } } else if (S_ISDIR(VFS_I(ip)->i_mode)) { if (XFS_TEST_ERROR( ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS && ip->i_df.if_format != XFS_DINODE_FMT_BTREE && ip->i_df.if_format != XFS_DINODE_FMT_LOCAL, mp, XFS_ERRTAG_IFLUSH_4)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: Bad directory inode %Lu, ptr "PTR_FMT, __func__, ip->i_ino, ip); goto flush_out; } } if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp) > ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: detected corrupt incore inode %Lu, " "total extents = %d, nblocks = %Ld, ptr "PTR_FMT, __func__, ip->i_ino, ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp), ip->i_d.di_nblocks, ip); goto flush_out; } if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize, mp, XFS_ERRTAG_IFLUSH_6)) { xfs_alert_tag(mp, XFS_PTAG_IFLUSH, "%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT, __func__, ip->i_ino, ip->i_d.di_forkoff, ip); goto flush_out; } /* * Inode item log recovery for 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 (!xfs_sb_version_has_v3inode(&mp->m_sb)) ip->i_d.di_flushiter++; /* * If there are inline format data / attr forks attached to this inode, * make sure they are not corrupt. */ if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL && xfs_ifork_verify_local_data(ip)) goto flush_out; if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL && xfs_ifork_verify_local_attr(ip)) goto flush_out; /* * 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_inode_to_disk(ip, dip, iip->ili_item.li_lsn); /* 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; xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK); if (XFS_IFORK_Q(ip)) xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK); /* * 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_buf_inode_iodone() 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. */ error = 0; flush_out: spin_lock(&iip->ili_lock); iip->ili_last_fields = iip->ili_fields; iip->ili_fields = 0; iip->ili_fsync_fields = 0; spin_unlock(&iip->ili_lock); /* * Store the current LSN of the inode so that we can tell whether the * item has moved in the AIL from xfs_buf_inode_iodone(). */ xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn, &iip->ili_item.li_lsn); /* generate the checksum. */ xfs_dinode_calc_crc(mp, dip); return error; } /* * Non-blocking flush of dirty inode metadata into the backing buffer. * * The caller must have a reference to the inode and hold the cluster buffer * locked. The function will walk across all the inodes on the cluster buffer it * can find and lock without blocking, and flush them to the cluster buffer. * * On successful flushing of at least one inode, the caller must write out the * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and * the caller needs to release the buffer. On failure, the filesystem will be * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED * will be returned. */ int xfs_iflush_cluster( struct xfs_buf *bp) { struct xfs_mount *mp = bp->b_mount; struct xfs_log_item *lip, *n; struct xfs_inode *ip; struct xfs_inode_log_item *iip; int clcount = 0; int error = 0; /* * We must use the safe variant here as on shutdown xfs_iflush_abort() * can remove itself from the list. */ list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { iip = (struct xfs_inode_log_item *)lip; ip = iip->ili_inode; /* * Quick and dirty check to avoid locks if possible. */ if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) continue; if (xfs_ipincount(ip)) continue; /* * The inode is still attached to the buffer, which means it is * dirty but reclaim might try to grab it. Check carefully for * that, and grab the ilock while still holding the i_flags_lock * to guarantee reclaim will not be able to reclaim this inode * once we drop the i_flags_lock. */ spin_lock(&ip->i_flags_lock); ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE)); if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) { spin_unlock(&ip->i_flags_lock); continue; } /* * ILOCK will pin the inode against reclaim and prevent * concurrent transactions modifying the inode while we are * flushing the inode. If we get the lock, set the flushing * state before we drop the i_flags_lock. */ if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) { spin_unlock(&ip->i_flags_lock); continue; } __xfs_iflags_set(ip, XFS_IFLUSHING); spin_unlock(&ip->i_flags_lock); /* * Abort flushing this inode if we are shut down because the * inode may not currently be in the AIL. This can occur when * log I/O failure unpins the inode without inserting into the * AIL, leaving a dirty/unpinned inode attached to the buffer * that otherwise looks like it should be flushed. */ if (XFS_FORCED_SHUTDOWN(mp)) { xfs_iunpin_wait(ip); xfs_iflush_abort(ip); xfs_iunlock(ip, XFS_ILOCK_SHARED); error = -EIO; continue; } /* don't block waiting on a log force to unpin dirty inodes */ if (xfs_ipincount(ip)) { xfs_iflags_clear(ip, XFS_IFLUSHING); xfs_iunlock(ip, XFS_ILOCK_SHARED); continue; } if (!xfs_inode_clean(ip)) error = xfs_iflush(ip, bp); else xfs_iflags_clear(ip, XFS_IFLUSHING); xfs_iunlock(ip, XFS_ILOCK_SHARED); if (error) break; clcount++; } if (error) { bp->b_flags |= XBF_ASYNC; xfs_buf_ioend_fail(bp); xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); return error; } if (!clcount) return -EAGAIN; XFS_STATS_INC(mp, xs_icluster_flushcnt); XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount); return 0; } /* Release an inode. */ void xfs_irele( struct xfs_inode *ip) { trace_xfs_irele(ip, _RET_IP_); iput(VFS_I(ip)); } /* * Ensure all commited transactions touching the inode are written to the log. */ int xfs_log_force_inode( struct xfs_inode *ip) { xfs_lsn_t lsn = 0; xfs_ilock(ip, XFS_ILOCK_SHARED); if (xfs_ipincount(ip)) lsn = ip->i_itemp->ili_last_lsn; xfs_iunlock(ip, XFS_ILOCK_SHARED); if (!lsn) return 0; return xfs_log_force_lsn(ip->i_mount, lsn, XFS_LOG_SYNC, NULL); } /* * Grab the exclusive iolock for a data copy from src to dest, making sure to * abide vfs locking order (lowest pointer value goes first) and breaking the * layout leases before proceeding. The loop is needed because we cannot call * the blocking break_layout() with the iolocks held, and therefore have to * back out both locks. */ static int xfs_iolock_two_inodes_and_break_layout( struct inode *src, struct inode *dest) { int error; if (src > dest) swap(src, dest); retry: /* Wait to break both inodes' layouts before we start locking. */ error = break_layout(src, true); if (error) return error; if (src != dest) { error = break_layout(dest, true); if (error) return error; } /* Lock one inode and make sure nobody got in and leased it. */ inode_lock(src); error = break_layout(src, false); if (error) { inode_unlock(src); if (error == -EWOULDBLOCK) goto retry; return error; } if (src == dest) return 0; /* Lock the other inode and make sure nobody got in and leased it. */ inode_lock_nested(dest, I_MUTEX_NONDIR2); error = break_layout(dest, false); if (error) { inode_unlock(src); inode_unlock(dest); if (error == -EWOULDBLOCK) goto retry; return error; } return 0; } /* * Lock two inodes so that userspace cannot initiate I/O via file syscalls or * mmap activity. */ int xfs_ilock2_io_mmap( struct xfs_inode *ip1, struct xfs_inode *ip2) { int ret; ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); if (ret) return ret; if (ip1 == ip2) xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); else xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL, ip2, XFS_MMAPLOCK_EXCL); return 0; } /* Unlock both inodes to allow IO and mmap activity. */ void xfs_iunlock2_io_mmap( struct xfs_inode *ip1, struct xfs_inode *ip2) { bool same_inode = (ip1 == ip2); xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); if (!same_inode) xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); inode_unlock(VFS_I(ip2)); if (!same_inode) inode_unlock(VFS_I(ip1)); }