/*****************************************************************************\ * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. * Copyright (C) 2007 The Regents of the University of California. * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). * Written by Brian Behlendorf . * UCRL-CODE-235197 * * This file is part of the SPL, Solaris Porting Layer. * For details, see . * * The SPL is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. * * The SPL is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. * * You should have received a copy of the GNU General Public License along * with the SPL. If not, see . ***************************************************************************** * Solaris Porting Layer (SPL) Vnode Implementation. \*****************************************************************************/ #include #include #include #include #include vnode_t *rootdir = (vnode_t *)0xabcd1234; EXPORT_SYMBOL(rootdir); static spl_kmem_cache_t *vn_cache; static spl_kmem_cache_t *vn_file_cache; static DEFINE_SPINLOCK(vn_file_lock); static LIST_HEAD(vn_file_list); vtype_t vn_mode_to_vtype(mode_t mode) { if (S_ISREG(mode)) return VREG; if (S_ISDIR(mode)) return VDIR; if (S_ISCHR(mode)) return VCHR; if (S_ISBLK(mode)) return VBLK; if (S_ISFIFO(mode)) return VFIFO; if (S_ISLNK(mode)) return VLNK; if (S_ISSOCK(mode)) return VSOCK; if (S_ISCHR(mode)) return VCHR; return VNON; } /* vn_mode_to_vtype() */ EXPORT_SYMBOL(vn_mode_to_vtype); mode_t vn_vtype_to_mode(vtype_t vtype) { if (vtype == VREG) return S_IFREG; if (vtype == VDIR) return S_IFDIR; if (vtype == VCHR) return S_IFCHR; if (vtype == VBLK) return S_IFBLK; if (vtype == VFIFO) return S_IFIFO; if (vtype == VLNK) return S_IFLNK; if (vtype == VSOCK) return S_IFSOCK; return VNON; } /* vn_vtype_to_mode() */ EXPORT_SYMBOL(vn_vtype_to_mode); vnode_t * vn_alloc(int flag) { vnode_t *vp; vp = kmem_cache_alloc(vn_cache, flag); if (vp != NULL) { vp->v_file = NULL; vp->v_type = 0; } return (vp); } /* vn_alloc() */ EXPORT_SYMBOL(vn_alloc); void vn_free(vnode_t *vp) { kmem_cache_free(vn_cache, vp); } /* vn_free() */ EXPORT_SYMBOL(vn_free); int vn_open(const char *path, uio_seg_t seg, int flags, int mode, vnode_t **vpp, int x1, void *x2) { struct file *fp; struct kstat stat; int rc, saved_umask = 0; gfp_t saved_gfp; vnode_t *vp; ASSERT(flags & (FWRITE | FREAD)); ASSERT(seg == UIO_SYSSPACE); ASSERT(vpp); *vpp = NULL; if (!(flags & FCREAT) && (flags & FWRITE)) flags |= FEXCL; /* Note for filp_open() the two low bits must be remapped to mean: * 01 - read-only -> 00 read-only * 10 - write-only -> 01 write-only * 11 - read-write -> 10 read-write */ flags--; if (flags & FCREAT) saved_umask = xchg(¤t->fs->umask, 0); fp = filp_open(path, flags, mode); if (flags & FCREAT) (void)xchg(¤t->fs->umask, saved_umask); if (IS_ERR(fp)) return (-PTR_ERR(fp)); #ifdef HAVE_2ARGS_VFS_GETATTR rc = vfs_getattr(&fp->f_path, &stat); #else rc = vfs_getattr(fp->f_path.mnt, fp->f_dentry, &stat); #endif if (rc) { filp_close(fp, 0); return (-rc); } vp = vn_alloc(KM_SLEEP); if (!vp) { filp_close(fp, 0); return (ENOMEM); } saved_gfp = mapping_gfp_mask(fp->f_mapping); mapping_set_gfp_mask(fp->f_mapping, saved_gfp & ~(__GFP_IO|__GFP_FS)); mutex_enter(&vp->v_lock); vp->v_type = vn_mode_to_vtype(stat.mode); vp->v_file = fp; vp->v_gfp_mask = saved_gfp; *vpp = vp; mutex_exit(&vp->v_lock); return (0); } /* vn_open() */ EXPORT_SYMBOL(vn_open); int vn_openat(const char *path, uio_seg_t seg, int flags, int mode, vnode_t **vpp, int x1, void *x2, vnode_t *vp, int fd) { char *realpath; int len, rc; ASSERT(vp == rootdir); len = strlen(path) + 2; realpath = kmalloc(len, kmem_flags_convert(KM_SLEEP)); if (!realpath) return (ENOMEM); (void)snprintf(realpath, len, "/%s", path); rc = vn_open(realpath, seg, flags, mode, vpp, x1, x2); kfree(realpath); return (rc); } /* vn_openat() */ EXPORT_SYMBOL(vn_openat); int vn_rdwr(uio_rw_t uio, vnode_t *vp, void *addr, ssize_t len, offset_t off, uio_seg_t seg, int ioflag, rlim64_t x2, void *x3, ssize_t *residp) { loff_t offset; mm_segment_t saved_fs; struct file *fp; int rc; ASSERT(uio == UIO_WRITE || uio == UIO_READ); ASSERT(vp); ASSERT(vp->v_file); ASSERT(seg == UIO_SYSSPACE); ASSERT((ioflag & ~FAPPEND) == 0); fp = vp->v_file; offset = off; if (ioflag & FAPPEND) offset = fp->f_pos; /* Writable user data segment must be briefly increased for this * process so we can use the user space read call paths to write * in to memory allocated by the kernel. */ saved_fs = get_fs(); set_fs(get_ds()); if (uio & UIO_WRITE) rc = vfs_write(fp, addr, len, &offset); else rc = vfs_read(fp, addr, len, &offset); set_fs(saved_fs); fp->f_pos = offset; if (rc < 0) return (-rc); if (residp) { *residp = len - rc; } else { if (rc != len) return (EIO); } return (0); } /* vn_rdwr() */ EXPORT_SYMBOL(vn_rdwr); int vn_close(vnode_t *vp, int flags, int x1, int x2, void *x3, void *x4) { int rc; ASSERT(vp); ASSERT(vp->v_file); mapping_set_gfp_mask(vp->v_file->f_mapping, vp->v_gfp_mask); rc = filp_close(vp->v_file, 0); vn_free(vp); return (-rc); } /* vn_close() */ EXPORT_SYMBOL(vn_close); /* vn_seek() does not actually seek it only performs bounds checking on the * proposed seek. We perform minimal checking and allow vn_rdwr() to catch * anything more serious. */ int vn_seek(vnode_t *vp, offset_t ooff, offset_t *noffp, void *ct) { return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0); } EXPORT_SYMBOL(vn_seek); /* * spl_basename() takes a NULL-terminated string s as input containing a path. * It returns a char pointer to a string and a length that describe the * basename of the path. If the basename is not "." or "/", it will be an index * into the string. While the string should be NULL terminated, the section * referring to the basename is not. spl_basename is dual-licensed GPLv2+ and * CC0. Anyone wishing to reuse it in another codebase may pick either license. */ static void spl_basename(const char *s, const char **str, int *len) { size_t i, end; ASSERT(str); ASSERT(len); if (!s || !*s) { *str = "."; *len = 1; return; } i = strlen(s) - 1; while (i && s[i--] == '/'); if (i == 0) { *str = "/"; *len = 1; return; } end = i; for (end = i; i; i--) { if (s[i] == '/') { *str = &s[i+1]; *len = end - i + 1; return; } } *str = s; *len = end + 1; } static struct dentry * spl_kern_path_locked(const char *name, struct path *path) { struct path parent; struct dentry *dentry; const char *basename; int len; int rc; ASSERT(name); ASSERT(path); spl_basename(name, &basename, &len); /* We do not accept "." or ".." */ if (len <= 2 && basename[0] == '.') if (len == 1 || basename[1] == '.') return (ERR_PTR(-EACCES)); rc = kern_path(name, LOOKUP_PARENT, &parent); if (rc) return (ERR_PTR(rc)); /* use I_MUTEX_PARENT because vfs_unlink needs it */ spl_inode_lock_nested(parent.dentry->d_inode, I_MUTEX_PARENT); dentry = lookup_one_len(basename, parent.dentry, len); if (IS_ERR(dentry)) { spl_inode_unlock(parent.dentry->d_inode); path_put(&parent); } else { *path = parent; } return (dentry); } /* Based on do_unlinkat() from linux/fs/namei.c */ int vn_remove(const char *path, uio_seg_t seg, int flags) { struct dentry *dentry; struct path parent; struct inode *inode = NULL; int rc = 0; ASSERT(seg == UIO_SYSSPACE); ASSERT(flags == RMFILE); dentry = spl_kern_path_locked(path, &parent); rc = PTR_ERR(dentry); if (!IS_ERR(dentry)) { if (parent.dentry->d_name.name[parent.dentry->d_name.len]) { rc = 0; goto slashes; } inode = dentry->d_inode; if (inode) { atomic_inc(&inode->i_count); } else { rc = 0; goto slashes; } #ifdef HAVE_2ARGS_VFS_UNLINK rc = vfs_unlink(parent.dentry->d_inode, dentry); #else rc = vfs_unlink(parent.dentry->d_inode, dentry, NULL); #endif /* HAVE_2ARGS_VFS_UNLINK */ exit1: dput(dentry); } else { return (-rc); } spl_inode_unlock(parent.dentry->d_inode); if (inode) iput(inode); /* truncate the inode here */ path_put(&parent); return (-rc); slashes: rc = !dentry->d_inode ? -ENOENT : S_ISDIR(dentry->d_inode->i_mode) ? -EISDIR : -ENOTDIR; goto exit1; } /* vn_remove() */ EXPORT_SYMBOL(vn_remove); /* Based on do_rename() from linux/fs/namei.c */ int vn_rename(const char *oldname, const char *newname, int x1) { struct dentry *old_dir, *new_dir; struct dentry *old_dentry, *new_dentry; struct dentry *trap; struct path old_parent, new_parent; int rc = 0; old_dentry = spl_kern_path_locked(oldname, &old_parent); if (IS_ERR(old_dentry)) { rc = PTR_ERR(old_dentry); goto exit; } spl_inode_unlock(old_parent.dentry->d_inode); new_dentry = spl_kern_path_locked(newname, &new_parent); if (IS_ERR(new_dentry)) { rc = PTR_ERR(new_dentry); goto exit2; } spl_inode_unlock(new_parent.dentry->d_inode); rc = -EXDEV; if (old_parent.mnt != new_parent.mnt) goto exit3; old_dir = old_parent.dentry; new_dir = new_parent.dentry; trap = lock_rename(new_dir, old_dir); /* source should not be ancestor of target */ rc = -EINVAL; if (old_dentry == trap) goto exit4; /* target should not be an ancestor of source */ rc = -ENOTEMPTY; if (new_dentry == trap) goto exit4; /* source must exist */ rc = -ENOENT; if (!old_dentry->d_inode) goto exit4; /* unless the source is a directory trailing slashes give -ENOTDIR */ if (!S_ISDIR(old_dentry->d_inode->i_mode)) { rc = -ENOTDIR; if (old_dentry->d_name.name[old_dentry->d_name.len]) goto exit4; if (new_dentry->d_name.name[new_dentry->d_name.len]) goto exit4; } #if defined(HAVE_4ARGS_VFS_RENAME) rc = vfs_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, new_dentry); #elif defined(HAVE_5ARGS_VFS_RENAME) rc = vfs_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, new_dentry, NULL); #else rc = vfs_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, new_dentry, NULL, 0); #endif exit4: unlock_rename(new_dir, old_dir); exit3: dput(new_dentry); path_put(&new_parent); exit2: dput(old_dentry); path_put(&old_parent); exit: return (-rc); } EXPORT_SYMBOL(vn_rename); int vn_getattr(vnode_t *vp, vattr_t *vap, int flags, void *x3, void *x4) { struct file *fp; struct kstat stat; int rc; ASSERT(vp); ASSERT(vp->v_file); ASSERT(vap); fp = vp->v_file; #ifdef HAVE_2ARGS_VFS_GETATTR rc = vfs_getattr(&fp->f_path, &stat); #else rc = vfs_getattr(fp->f_path.mnt, fp->f_dentry, &stat); #endif if (rc) return (-rc); vap->va_type = vn_mode_to_vtype(stat.mode); vap->va_mode = stat.mode; vap->va_uid = KUID_TO_SUID(stat.uid); vap->va_gid = KGID_TO_SGID(stat.gid); vap->va_fsid = 0; vap->va_nodeid = stat.ino; vap->va_nlink = stat.nlink; vap->va_size = stat.size; vap->va_blksize = stat.blksize; vap->va_atime = stat.atime; vap->va_mtime = stat.mtime; vap->va_ctime = stat.ctime; vap->va_rdev = stat.rdev; vap->va_nblocks = stat.blocks; return (0); } EXPORT_SYMBOL(vn_getattr); int vn_fsync(vnode_t *vp, int flags, void *x3, void *x4) { int datasync = 0; int error; int fstrans; ASSERT(vp); ASSERT(vp->v_file); if (flags & FDSYNC) datasync = 1; /* * May enter XFS which generates a warning when PF_FSTRANS is set. * To avoid this the flag is cleared over vfs_sync() and then reset. */ fstrans = spl_fstrans_check(); if (fstrans) current->flags &= ~(PF_FSTRANS); error = -spl_filp_fsync(vp->v_file, datasync); if (fstrans) current->flags |= PF_FSTRANS; return (error); } /* vn_fsync() */ EXPORT_SYMBOL(vn_fsync); int vn_space(vnode_t *vp, int cmd, struct flock *bfp, int flag, offset_t offset, void *x6, void *x7) { int error = EOPNOTSUPP; #ifdef FALLOC_FL_PUNCH_HOLE int fstrans; #endif if (cmd != F_FREESP || bfp->l_whence != 0) return (EOPNOTSUPP); ASSERT(vp); ASSERT(vp->v_file); ASSERT(bfp->l_start >= 0 && bfp->l_len > 0); #ifdef FALLOC_FL_PUNCH_HOLE /* * May enter XFS which generates a warning when PF_FSTRANS is set. * To avoid this the flag is cleared over vfs_sync() and then reset. */ fstrans = spl_fstrans_check(); if (fstrans) current->flags &= ~(PF_FSTRANS); /* * When supported by the underlying file system preferentially * use the fallocate() callback to preallocate the space. */ error = -spl_filp_fallocate(vp->v_file, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, bfp->l_start, bfp->l_len); if (fstrans) current->flags |= PF_FSTRANS; if (error == 0) return (0); #endif #ifdef HAVE_INODE_TRUNCATE_RANGE if (vp->v_file->f_dentry && vp->v_file->f_dentry->d_inode && vp->v_file->f_dentry->d_inode->i_op && vp->v_file->f_dentry->d_inode->i_op->truncate_range) { off_t end = bfp->l_start + bfp->l_len; /* * Judging from the code in shmem_truncate_range(), * it seems the kernel expects the end offset to be * inclusive and aligned to the end of a page. */ if (end % PAGE_SIZE != 0) { end &= ~(off_t)(PAGE_SIZE - 1); if (end <= bfp->l_start) return (0); } --end; vp->v_file->f_dentry->d_inode->i_op->truncate_range( vp->v_file->f_dentry->d_inode, bfp->l_start, end ); return (0); } #endif return (error); } EXPORT_SYMBOL(vn_space); /* Function must be called while holding the vn_file_lock */ static file_t * file_find(int fd, struct task_struct *task) { file_t *fp; ASSERT(spin_is_locked(&vn_file_lock)); list_for_each_entry(fp, &vn_file_list, f_list) { if (fd == fp->f_fd && fp->f_task == task) { ASSERT(atomic_read(&fp->f_ref) != 0); return fp; } } return NULL; } /* file_find() */ file_t * vn_getf(int fd) { struct kstat stat; struct file *lfp; file_t *fp; vnode_t *vp; int rc = 0; if (fd < 0) return (NULL); /* Already open just take an extra reference */ spin_lock(&vn_file_lock); fp = file_find(fd, current); if (fp) { lfp = fget(fd); fput(fp->f_file); /* * areleasef() can cause us to see a stale reference when * userspace has reused a file descriptor before areleasef() * has run. fput() the stale reference and replace it. We * retain the original reference count such that the concurrent * areleasef() will decrement its reference and terminate. */ if (lfp != fp->f_file) { fp->f_file = lfp; fp->f_vnode->v_file = lfp; } atomic_inc(&fp->f_ref); spin_unlock(&vn_file_lock); return (fp); } spin_unlock(&vn_file_lock); /* File was not yet opened create the object and setup */ fp = kmem_cache_alloc(vn_file_cache, KM_SLEEP); if (fp == NULL) goto out; mutex_enter(&fp->f_lock); fp->f_fd = fd; fp->f_task = current; fp->f_offset = 0; atomic_inc(&fp->f_ref); lfp = fget(fd); if (lfp == NULL) goto out_mutex; vp = vn_alloc(KM_SLEEP); if (vp == NULL) goto out_fget; #ifdef HAVE_2ARGS_VFS_GETATTR rc = vfs_getattr(&lfp->f_path, &stat); #else rc = vfs_getattr(lfp->f_path.mnt, lfp->f_dentry, &stat); #endif if (rc) goto out_vnode; mutex_enter(&vp->v_lock); vp->v_type = vn_mode_to_vtype(stat.mode); vp->v_file = lfp; mutex_exit(&vp->v_lock); fp->f_vnode = vp; fp->f_file = lfp; /* Put it on the tracking list */ spin_lock(&vn_file_lock); list_add(&fp->f_list, &vn_file_list); spin_unlock(&vn_file_lock); mutex_exit(&fp->f_lock); return (fp); out_vnode: vn_free(vp); out_fget: fput(lfp); out_mutex: mutex_exit(&fp->f_lock); kmem_cache_free(vn_file_cache, fp); out: return (NULL); } /* getf() */ EXPORT_SYMBOL(getf); static void releasef_locked(file_t *fp) { ASSERT(fp->f_file); ASSERT(fp->f_vnode); /* Unlinked from list, no refs, safe to free outside mutex */ fput(fp->f_file); vn_free(fp->f_vnode); kmem_cache_free(vn_file_cache, fp); } void vn_releasef(int fd) { areleasef(fd, P_FINFO(current)); } EXPORT_SYMBOL(releasef); void vn_areleasef(int fd, uf_info_t *fip) { file_t *fp; struct task_struct *task = (struct task_struct *)fip; if (fd < 0) return; spin_lock(&vn_file_lock); fp = file_find(fd, task); if (fp) { atomic_dec(&fp->f_ref); if (atomic_read(&fp->f_ref) > 0) { spin_unlock(&vn_file_lock); return; } list_del(&fp->f_list); releasef_locked(fp); } spin_unlock(&vn_file_lock); return; } /* releasef() */ EXPORT_SYMBOL(areleasef); static void #ifdef HAVE_SET_FS_PWD_WITH_CONST vn_set_fs_pwd(struct fs_struct *fs, const struct path *path) #else vn_set_fs_pwd(struct fs_struct *fs, struct path *path) #endif /* HAVE_SET_FS_PWD_WITH_CONST */ { struct path old_pwd; #ifdef HAVE_FS_STRUCT_SPINLOCK spin_lock(&fs->lock); old_pwd = fs->pwd; fs->pwd = *path; path_get(path); spin_unlock(&fs->lock); #else write_lock(&fs->lock); old_pwd = fs->pwd; fs->pwd = *path; path_get(path); write_unlock(&fs->lock); #endif /* HAVE_FS_STRUCT_SPINLOCK */ if (old_pwd.dentry) path_put(&old_pwd); } int vn_set_pwd(const char *filename) { struct path path; mm_segment_t saved_fs; int rc; /* * user_path_dir() and __user_walk() both expect 'filename' to be * a user space address so we must briefly increase the data segment * size to ensure strncpy_from_user() does not fail with -EFAULT. */ saved_fs = get_fs(); set_fs(get_ds()); rc = user_path_dir(filename, &path); if (rc) goto out; rc = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_ACCESS); if (rc) goto dput_and_out; vn_set_fs_pwd(current->fs, &path); dput_and_out: path_put(&path); out: set_fs(saved_fs); return (-rc); } /* vn_set_pwd() */ EXPORT_SYMBOL(vn_set_pwd); static int vn_cache_constructor(void *buf, void *cdrarg, int kmflags) { struct vnode *vp = buf; mutex_init(&vp->v_lock, NULL, MUTEX_DEFAULT, NULL); return (0); } /* vn_cache_constructor() */ static void vn_cache_destructor(void *buf, void *cdrarg) { struct vnode *vp = buf; mutex_destroy(&vp->v_lock); } /* vn_cache_destructor() */ static int vn_file_cache_constructor(void *buf, void *cdrarg, int kmflags) { file_t *fp = buf; atomic_set(&fp->f_ref, 0); mutex_init(&fp->f_lock, NULL, MUTEX_DEFAULT, NULL); INIT_LIST_HEAD(&fp->f_list); return (0); } /* file_cache_constructor() */ static void vn_file_cache_destructor(void *buf, void *cdrarg) { file_t *fp = buf; mutex_destroy(&fp->f_lock); } /* vn_file_cache_destructor() */ int spl_vn_init(void) { vn_cache = kmem_cache_create("spl_vn_cache", sizeof(struct vnode), 64, vn_cache_constructor, vn_cache_destructor, NULL, NULL, NULL, KMC_KMEM); vn_file_cache = kmem_cache_create("spl_vn_file_cache", sizeof(file_t), 64, vn_file_cache_constructor, vn_file_cache_destructor, NULL, NULL, NULL, KMC_KMEM); return (0); } /* vn_init() */ void spl_vn_fini(void) { file_t *fp, *next_fp; int leaked = 0; spin_lock(&vn_file_lock); list_for_each_entry_safe(fp, next_fp, &vn_file_list, f_list) { list_del(&fp->f_list); releasef_locked(fp); leaked++; } spin_unlock(&vn_file_lock); if (leaked > 0) printk(KERN_WARNING "WARNING: %d vnode files leaked\n", leaked); kmem_cache_destroy(vn_file_cache); kmem_cache_destroy(vn_cache); return; } /* vn_fini() */