diff options
Diffstat (limited to 'module/spl/spl-vnode.c')
| -rw-r--r-- | module/spl/spl-vnode.c | 779 |
1 files changed, 779 insertions, 0 deletions
diff --git a/module/spl/spl-vnode.c b/module/spl/spl-vnode.c new file mode 100644 index 000000000..28ce21276 --- /dev/null +++ b/module/spl/spl-vnode.c @@ -0,0 +1,779 @@ +/* + * 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 <[email protected]>. + * UCRL-CODE-235197 + * + * This file is part of the SPL, Solaris Porting Layer. + * For details, see <http://zfsonlinux.org/>. + * + * 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 <http://www.gnu.org/licenses/>. + * + * Solaris Porting Layer (SPL) Vnode Implementation. + */ + +#include <sys/cred.h> +#include <sys/vnode.h> +#include <sys/kmem_cache.h> +#include <linux/falloc.h> +#include <linux/fs.h> +#include <linux/uaccess.h> +#ifdef HAVE_FDTABLE_HEADER +#include <linux/fdtable.h> +#endif + +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); + +static int +spl_filp_fallocate(struct file *fp, int mode, loff_t offset, loff_t len) +{ + int error = -EOPNOTSUPP; + +#ifdef HAVE_FILE_FALLOCATE + if (fp->f_op->fallocate) + error = fp->f_op->fallocate(fp, mode, offset, len); +#else +#ifdef HAVE_INODE_FALLOCATE + if (fp->f_dentry && fp->f_dentry->d_inode && + fp->f_dentry->d_inode->i_op->fallocate) + error = fp->f_dentry->d_inode->i_op->fallocate( + fp->f_dentry->d_inode, mode, offset, len); +#endif /* HAVE_INODE_FALLOCATE */ +#endif /* HAVE_FILE_FALLOCATE */ + + return (error); +} + +static int +spl_filp_fsync(struct file *fp, int sync) +{ +#ifdef HAVE_2ARGS_VFS_FSYNC + return (vfs_fsync(fp, sync)); +#else + return (vfs_fsync(fp, (fp)->f_dentry, sync)); +#endif /* HAVE_2ARGS_VFS_FSYNC */ +} + +static ssize_t +spl_kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos) +{ +#if defined(HAVE_KERNEL_WRITE_PPOS) + return (kernel_write(file, buf, count, pos)); +#else + mm_segment_t saved_fs; + ssize_t ret; + + saved_fs = get_fs(); + set_fs(get_ds()); + + ret = vfs_write(file, (__force const char __user *)buf, count, pos); + + set_fs(saved_fs); + + return (ret); +#endif +} + +static ssize_t +spl_kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) +{ +#if defined(HAVE_KERNEL_READ_PPOS) + return (kernel_read(file, buf, count, pos)); +#else + mm_segment_t saved_fs; + ssize_t ret; + + saved_fs = get_fs(); + set_fs(get_ds()); + + ret = vfs_read(file, (void __user *)buf, count, pos); + + set_fs(saved_fs); + + return (ret); +#endif +} + +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); + + 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)); + +#if defined(HAVE_4ARGS_VFS_GETATTR) + rc = vfs_getattr(&fp->f_path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); +#elif defined(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) +{ + struct file *fp = vp->v_file; + loff_t offset = off; + int rc; + + ASSERT(uio == UIO_WRITE || uio == UIO_READ); + ASSERT(seg == UIO_SYSSPACE); + ASSERT((ioflag & ~FAPPEND) == 0); + + if (ioflag & FAPPEND) + offset = fp->f_pos; + + if (uio & UIO_WRITE) + rc = spl_kernel_write(fp, addr, len, &offset); + else + rc = spl_kernel_read(fp, addr, len, &offset); + + 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); + +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; + +#if defined(HAVE_4ARGS_VFS_GETATTR) + rc = vfs_getattr(&fp->f_path, &stat, STATX_BASIC_STATS, + AT_STATX_SYNC_AS_STAT); +#elif defined(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_pf_fstrans_check(); + if (fstrans) + current->flags &= ~(__SPL_PF_FSTRANS); + + error = -spl_filp_fsync(vp->v_file, datasync); + if (fstrans) + current->flags |= __SPL_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_pf_fstrans_check(); + if (fstrans) + current->flags &= ~(__SPL_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 |= __SPL_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; + + 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; + +#if defined(HAVE_4ARGS_VFS_GETATTR) + rc = vfs_getattr(&lfp->f_path, &stat, STATX_TYPE, + AT_STATX_SYNC_AS_STAT); +#elif defined(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); +} /* 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); +} /* vn_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, 0); + + 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, 0); + + return (0); +} /* spl_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); +} /* spl_vn_fini() */ |