ref: 8eff9f9971a1056ade031e646acb9b07a972fd65
dir: /src/ext4.c/
/* * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /** @addtogroup lwext4 * @{ */ /** * @file ext4.h * @brief Ext4 high level operations (file, directory, mountpoints...) */ #include "ext4_config.h" #include "ext4_types.h" #include "ext4_misc.h" #include "ext4_errno.h" #include "ext4_oflags.h" #include "ext4_debug.h" #include "ext4.h" #include "ext4_trans.h" #include "ext4_blockdev.h" #include "ext4_fs.h" #include "ext4_dir.h" #include "ext4_inode.h" #include "ext4_super.h" #include "ext4_block_group.h" #include "ext4_dir_idx.h" #include "ext4_xattr.h" #include "ext4_journal.h" #include <stdlib.h> #include <string.h> /**@brief Mount point OS dependent lock*/ #define EXT4_MP_LOCK(_m) \ do { \ if ((_m)->os_locks) \ (_m)->os_locks->lock(); \ } while (0) /**@brief Mount point OS dependent unlock*/ #define EXT4_MP_UNLOCK(_m) \ do { \ if ((_m)->os_locks) \ (_m)->os_locks->unlock(); \ } while (0) /**@brief Mount point descriptor.*/ struct ext4_mountpoint { /**@brief Mount done flag.*/ bool mounted; /**@brief Mount point name (@ref ext4_mount)*/ char name[32]; /**@brief OS dependent lock/unlock functions.*/ const struct ext4_lock *os_locks; /**@brief Ext4 filesystem internals.*/ struct ext4_fs fs; /**@brief Dynamic allocation cache flag.*/ bool cache_dynamic; struct jbd_fs jbd_fs; struct jbd_journal jbd_journal; }; /**@brief Block devices descriptor.*/ struct _ext4_devices { /**@brief Block device name (@ref ext4_device_register)*/ char name[32]; /**@brief Block device handle.*/ struct ext4_blockdev *bd; /**@brief Block cache handle.*/ struct ext4_bcache *bc; }; /**@brief Block devices.*/ struct _ext4_devices _bdevices[CONFIG_EXT4_BLOCKDEVS_COUNT]; /**@brief Mountpoints.*/ struct ext4_mountpoint _mp[CONFIG_EXT4_MOUNTPOINTS_COUNT]; int ext4_device_register(struct ext4_blockdev *bd, struct ext4_bcache *bc, const char *dev_name) { uint32_t i; ext4_assert(bd && dev_name); for (i = 0; i < CONFIG_EXT4_BLOCKDEVS_COUNT; ++i) { if (!_bdevices[i].bd) { strcpy(_bdevices[i].name, dev_name); _bdevices[i].bd = bd; _bdevices[i].bc = bc; return EOK; } if (!strcmp(_bdevices[i].name, dev_name)) return EOK; } return ENOSPC; } /****************************************************************************/ static bool ext4_is_dots(const uint8_t *name, size_t name_size) { if ((name_size == 1) && (name[0] == '.')) return true; if ((name_size == 2) && (name[0] == '.') && (name[1] == '.')) return true; return false; } static int ext4_has_children(bool *has_children, struct ext4_inode_ref *enode) { struct ext4_sblock *sb = &enode->fs->sb; /* Check if node is directory */ if (!ext4_inode_is_type(sb, enode->inode, EXT4_INODE_MODE_DIRECTORY)) { *has_children = false; return EOK; } struct ext4_dir_iter it; int rc = ext4_dir_iterator_init(&it, enode, 0); if (rc != EOK) return rc; /* Find a non-empty directory entry */ bool found = false; while (it.curr != NULL) { if (ext4_dir_en_get_inode(it.curr) != 0) { uint16_t nsize; nsize = ext4_dir_en_get_name_len(sb, it.curr); if (!ext4_is_dots(it.curr->name, nsize)) { found = true; break; } } rc = ext4_dir_iterator_next(&it); if (rc != EOK) { ext4_dir_iterator_fini(&it); return rc; } } rc = ext4_dir_iterator_fini(&it); if (rc != EOK) return rc; *has_children = found; return EOK; } static int ext4_link(struct ext4_mountpoint *mp, struct ext4_inode_ref *parent, struct ext4_inode_ref *ch, const char *n, uint32_t len, bool rename) { /* Check maximum name length */ if (len > EXT4_DIRECTORY_FILENAME_LEN) return EINVAL; /* Add entry to parent directory */ int r = ext4_dir_add_entry(parent, n, len, ch); if (r != EOK) return r; /* Fill new dir -> add '.' and '..' entries. * Also newly allocated inode should have 0 link count. */ bool is_dir = ext4_inode_is_type(&mp->fs.sb, ch->inode, EXT4_INODE_MODE_DIRECTORY); if (is_dir && !rename) { #if CONFIG_DIR_INDEX_ENABLE /* Initialize directory index if supported */ if (ext4_sb_feature_com(&mp->fs.sb, EXT4_FCOM_DIR_INDEX)) { r = ext4_dir_dx_init(ch, parent); if (r != EOK) return r; ext4_inode_set_flag(ch->inode, EXT4_INODE_FLAG_INDEX); ch->dirty = true; } else #endif { r = ext4_dir_add_entry(ch, ".", strlen("."), ch); if (r != EOK) { ext4_dir_remove_entry(parent, n, strlen(n)); return r; } r = ext4_dir_add_entry(ch, "..", strlen(".."), parent); if (r != EOK) { ext4_dir_remove_entry(parent, n, strlen(n)); ext4_dir_remove_entry(ch, ".", strlen(".")); return r; } } /*New empty directory. Two links (. and ..) */ ext4_inode_set_links_cnt(ch->inode, 2); ext4_fs_inode_links_count_inc(parent); ch->dirty = true; parent->dirty = true; return r; } /* * In case we want to rename a directory, * we reset the original '..' pointer. */ if (is_dir) { bool idx; idx = ext4_inode_has_flag(ch->inode, EXT4_INODE_FLAG_INDEX); struct ext4_dir_search_result res; if (!idx) { r = ext4_dir_find_entry(&res, ch, "..", strlen("..")); if (r != EOK) return EIO; ext4_dir_en_set_inode(res.dentry, parent->index); ext4_trans_set_block_dirty(res.block.buf); r = ext4_dir_destroy_result(ch, &res); if (r != EOK) return r; } else { #if CONFIG_DIR_INDEX_ENABLE r = ext4_dir_dx_reset_parent_inode(ch, parent->index); if (r != EOK) return r; #endif } ext4_fs_inode_links_count_inc(parent); parent->dirty = true; } if (!rename) { ext4_fs_inode_links_count_inc(ch); ch->dirty = true; } return r; } static int ext4_unlink(struct ext4_mountpoint *mp, struct ext4_inode_ref *parent, struct ext4_inode_ref *child, const char *name, uint32_t name_len) { bool has_children; int rc = ext4_has_children(&has_children, child); if (rc != EOK) return rc; /* Cannot unlink non-empty node */ if (has_children) return ENOTEMPTY; /* Remove entry from parent directory */ rc = ext4_dir_remove_entry(parent, name, name_len); if (rc != EOK) return rc; bool is_dir = ext4_inode_is_type(&mp->fs.sb, child->inode, EXT4_INODE_MODE_DIRECTORY); /* If directory - handle links from parent */ if (is_dir) { ext4_fs_inode_links_count_dec(parent); parent->dirty = true; } /* * TODO: Update timestamps of the parent * (when we have wall-clock time). * * ext4_inode_set_change_inode_time(parent->inode, (uint32_t) now); * ext4_inode_set_modification_time(parent->inode, (uint32_t) now); * parent->dirty = true; */ /* * TODO: Update timestamp for inode. * * ext4_inode_set_change_inode_time(child->inode, * (uint32_t) now); */ if (ext4_inode_get_links_cnt(child->inode)) { ext4_fs_inode_links_count_dec(child); child->dirty = true; } return EOK; } /****************************************************************************/ int ext4_mount(const char *dev_name, const char *mount_point, bool read_only) { ext4_assert(mount_point && dev_name); int r; int i; uint32_t bsize; struct ext4_blockdev *bd = 0; struct ext4_bcache *bc = 0; struct ext4_mountpoint *mp = 0; if (mount_point[strlen(mount_point) - 1] != '/') return ENOTSUP; for (i = 0; i < CONFIG_EXT4_BLOCKDEVS_COUNT; ++i) { if (_bdevices[i].name) { if (!strcmp(dev_name, _bdevices[i].name)) { bd = _bdevices[i].bd; bc = _bdevices[i].bc; break; } } } if (!bd) return ENODEV; for (i = 0; i < CONFIG_EXT4_MOUNTPOINTS_COUNT; ++i) { if (!_mp[i].mounted) { strcpy(_mp[i].name, mount_point); _mp[i].mounted = 1; mp = &_mp[i]; break; } if (!strcmp(_mp[i].name, mount_point)) return EOK; } if (!mp) return ENOMEM; r = ext4_block_init(bd); if (r != EOK) return r; r = ext4_fs_init(&mp->fs, bd, read_only); if (r != EOK) { ext4_block_fini(bd); return r; } bsize = ext4_sb_get_block_size(&mp->fs.sb); ext4_block_set_lb_size(bd, bsize); mp->cache_dynamic = 0; if (!bc) { /*Automatic block cache alloc.*/ mp->cache_dynamic = 1; bc = malloc(sizeof(struct ext4_bcache)); r = ext4_bcache_init_dynamic(bc, CONFIG_BLOCK_DEV_CACHE_SIZE, bsize); if (r != EOK) { free(bc); ext4_block_fini(bd); return r; } } if (bsize != bc->itemsize) return ENOTSUP; /*Bind block cache to block device*/ r = ext4_block_bind_bcache(bd, bc); if (r != EOK) { ext4_bcache_cleanup(bc); ext4_block_fini(bd); if (mp->cache_dynamic) { ext4_bcache_fini_dynamic(bc); free(bc); } return r; } bd->fs = &mp->fs; return r; } int ext4_umount(const char *mount_point) { int i; int r; struct ext4_mountpoint *mp = 0; for (i = 0; i < CONFIG_EXT4_MOUNTPOINTS_COUNT; ++i) { if (!strcmp(_mp[i].name, mount_point)) { mp = &_mp[i]; break; } } if (!mp) return ENODEV; r = ext4_fs_fini(&mp->fs); if (r != EOK) goto Finish; mp->mounted = 0; ext4_bcache_cleanup(mp->fs.bdev->bc); if (mp->cache_dynamic) { ext4_bcache_fini_dynamic(mp->fs.bdev->bc); free(mp->fs.bdev->bc); } r = ext4_block_fini(mp->fs.bdev); Finish: mp->fs.bdev->fs = NULL; return r; } static struct ext4_mountpoint *ext4_get_mount(const char *path) { int i; for (i = 0; i < CONFIG_EXT4_MOUNTPOINTS_COUNT; ++i) { if (!_mp[i].mounted) continue; if (!strncmp(_mp[i].name, path, strlen(_mp[i].name))) return &_mp[i]; } return NULL; } __unused static int __ext4_journal_start(const char *mount_point) { int r = EOK; struct ext4_mountpoint *mp = ext4_get_mount(mount_point); if (!mp) return ENOENT; if (mp->fs.read_only) return EOK; if (ext4_sb_feature_com(&mp->fs.sb, EXT4_FCOM_HAS_JOURNAL)) { r = jbd_get_fs(&mp->fs, &mp->jbd_fs); if (r != EOK) goto Finish; r = jbd_journal_start(&mp->jbd_fs, &mp->jbd_journal); if (r != EOK) { mp->jbd_fs.dirty = false; jbd_put_fs(&mp->jbd_fs); goto Finish; } mp->fs.jbd_fs = &mp->jbd_fs; mp->fs.jbd_journal = &mp->jbd_journal; } Finish: return r; } __unused static int __ext4_journal_stop(const char *mount_point) { int r = EOK; struct ext4_mountpoint *mp = ext4_get_mount(mount_point); if (!mp) return ENOENT; if (mp->fs.read_only) return EOK; if (ext4_sb_feature_com(&mp->fs.sb, EXT4_FCOM_HAS_JOURNAL)) { r = jbd_journal_stop(&mp->jbd_journal); if (r != EOK) { mp->jbd_fs.dirty = false; jbd_put_fs(&mp->jbd_fs); mp->fs.jbd_journal = NULL; mp->fs.jbd_fs = NULL; goto Finish; } r = jbd_put_fs(&mp->jbd_fs); if (r != EOK) { mp->fs.jbd_journal = NULL; mp->fs.jbd_fs = NULL; goto Finish; } mp->fs.jbd_journal = NULL; mp->fs.jbd_fs = NULL; } Finish: return r; } __unused static int __ext4_recover(const char *mount_point) { struct ext4_mountpoint *mp = ext4_get_mount(mount_point); if (!mp) return ENOENT; int r = ENOTSUP; EXT4_MP_LOCK(mp); if (ext4_sb_feature_com(&mp->fs.sb, EXT4_FCOM_HAS_JOURNAL)) { struct jbd_fs *jbd_fs = calloc(1, sizeof(struct jbd_fs)); if (!jbd_fs) { r = ENOMEM; goto Finish; } r = jbd_get_fs(&mp->fs, jbd_fs); if (r != EOK) { free(jbd_fs); goto Finish; } r = jbd_recover(jbd_fs); jbd_put_fs(jbd_fs); free(jbd_fs); } if (r == EOK && !mp->fs.read_only) { uint32_t bgid; uint64_t free_blocks_count = 0; uint32_t free_inodes_count = 0; struct ext4_block_group_ref bg_ref; /* Update superblock's stats */ for (bgid = 0;bgid < ext4_block_group_cnt(&mp->fs.sb);bgid++) { r = ext4_fs_get_block_group_ref(&mp->fs, bgid, &bg_ref); if (r != EOK) goto Finish; free_blocks_count += ext4_bg_get_free_blocks_count(bg_ref.block_group, &mp->fs.sb); free_inodes_count += ext4_bg_get_free_inodes_count(bg_ref.block_group, &mp->fs.sb); ext4_fs_put_block_group_ref(&bg_ref); } ext4_sb_set_free_blocks_cnt(&mp->fs.sb, free_blocks_count); ext4_set32(&mp->fs.sb, free_inodes_count, free_inodes_count); /* We don't need to save the superblock stats immediately. */ } Finish: EXT4_MP_UNLOCK(mp); return r; } __unused static int __ext4_trans_start(struct ext4_mountpoint *mp) { int r = EOK; if (mp->fs.jbd_journal && !mp->fs.curr_trans) { struct jbd_journal *journal = mp->fs.jbd_journal; struct jbd_trans *trans; trans = jbd_journal_new_trans(journal); if (!trans) { r = ENOMEM; goto Finish; } mp->fs.curr_trans = trans; } Finish: return r; } __unused static int __ext4_trans_stop(struct ext4_mountpoint *mp) { int r = EOK; if (mp->fs.jbd_journal && mp->fs.curr_trans) { struct jbd_journal *journal = mp->fs.jbd_journal; struct jbd_trans *trans = mp->fs.curr_trans; r = jbd_journal_commit_trans(journal, trans); mp->fs.curr_trans = NULL; } return r; } __unused static void __ext4_trans_abort(struct ext4_mountpoint *mp) { if (mp->fs.jbd_journal && mp->fs.curr_trans) { struct jbd_journal *journal = mp->fs.jbd_journal; struct jbd_trans *trans = mp->fs.curr_trans; jbd_journal_free_trans(journal, trans, true); mp->fs.curr_trans = NULL; } } int ext4_journal_start(const char *mount_point __unused) { int r = EOK; #if CONFIG_JOURNALING_ENABLE r = __ext4_journal_start(mount_point); #endif return r; } int ext4_journal_stop(const char *mount_point __unused) { int r = EOK; #if CONFIG_JOURNALING_ENABLE r = __ext4_journal_stop(mount_point); #endif return r; } int ext4_recover(const char *mount_point __unused) { int r = EOK; #if CONFIG_JOURNALING_ENABLE r = __ext4_recover(mount_point); #endif return r; } static int ext4_trans_start(struct ext4_mountpoint *mp __unused) { int r = EOK; #if CONFIG_JOURNALING_ENABLE r = __ext4_trans_start(mp); #endif return r; } static int ext4_trans_stop(struct ext4_mountpoint *mp __unused) { int r = EOK; #if CONFIG_JOURNALING_ENABLE r = __ext4_trans_stop(mp); #endif return r; } static void ext4_trans_abort(struct ext4_mountpoint *mp __unused) { #if CONFIG_JOURNALING_ENABLE __ext4_trans_abort(mp); #endif } int ext4_mount_point_stats(const char *mount_point, struct ext4_mount_stats *stats) { struct ext4_mountpoint *mp = ext4_get_mount(mount_point); if (!mp) return ENOENT; EXT4_MP_LOCK(mp); stats->inodes_count = ext4_get32(&mp->fs.sb, inodes_count); stats->free_inodes_count = ext4_get32(&mp->fs.sb, free_inodes_count); stats->blocks_count = ext4_sb_get_blocks_cnt(&mp->fs.sb); stats->free_blocks_count = ext4_sb_get_free_blocks_cnt(&mp->fs.sb); stats->block_size = ext4_sb_get_block_size(&mp->fs.sb); stats->block_group_count = ext4_block_group_cnt(&mp->fs.sb); stats->blocks_per_group = ext4_get32(&mp->fs.sb, blocks_per_group); stats->inodes_per_group = ext4_get32(&mp->fs.sb, inodes_per_group); memcpy(stats->volume_name, mp->fs.sb.volume_name, 16); EXT4_MP_UNLOCK(mp); return EOK; } int ext4_mount_setup_locks(const char *mount_point, const struct ext4_lock *locks) { uint32_t i; struct ext4_mountpoint *mp = 0; for (i = 0; i < CONFIG_EXT4_MOUNTPOINTS_COUNT; ++i) { if (!strcmp(_mp[i].name, mount_point)) { mp = &_mp[i]; break; } } if (!mp) return ENOENT; mp->os_locks = locks; return EOK; } /********************************FILE OPERATIONS*****************************/ static int ext4_path_check(const char *path, bool *is_goal) { int i; for (i = 0; i < EXT4_DIRECTORY_FILENAME_LEN; ++i) { if (path[i] == '/') { *is_goal = false; return i; } if (path[i] == 0) { *is_goal = true; return i; } } return 0; } static bool ext4_parse_flags(const char *flags, uint32_t *file_flags) { if (!flags) return false; if (!strcmp(flags, "r") || !strcmp(flags, "rb")) { *file_flags = O_RDONLY; return true; } if (!strcmp(flags, "w") || !strcmp(flags, "wb")) { *file_flags = O_WRONLY | O_CREAT | O_TRUNC; return true; } if (!strcmp(flags, "a") || !strcmp(flags, "ab")) { *file_flags = O_WRONLY | O_CREAT | O_APPEND; return true; } if (!strcmp(flags, "r+") || !strcmp(flags, "rb+") || !strcmp(flags, "r+b")) { *file_flags = O_RDWR; return true; } if (!strcmp(flags, "w+") || !strcmp(flags, "wb+") || !strcmp(flags, "w+b")) { *file_flags = O_RDWR | O_CREAT | O_TRUNC; return true; } if (!strcmp(flags, "a+") || !strcmp(flags, "ab+") || !strcmp(flags, "a+b")) { *file_flags = O_RDWR | O_CREAT | O_APPEND; return true; } return false; } static int ext4_trunc_inode(struct ext4_mountpoint *mp, uint32_t index, uint64_t new_size) { int r = EOK; struct ext4_fs *const fs = &mp->fs; struct ext4_inode_ref inode_ref; uint64_t inode_size; bool has_trans = mp->fs.jbd_journal && mp->fs.curr_trans; r = ext4_fs_get_inode_ref(fs, index, &inode_ref); if (r != EOK) return r; inode_size = ext4_inode_get_size(&fs->sb, inode_ref.inode); ext4_fs_put_inode_ref(&inode_ref); if (has_trans) ext4_trans_stop(mp); while (inode_size > new_size + CONFIG_MAX_TRUNCATE_SIZE) { inode_size -= CONFIG_MAX_TRUNCATE_SIZE; ext4_trans_start(mp); r = ext4_fs_get_inode_ref(fs, index, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); break; } r = ext4_fs_truncate_inode(&inode_ref, inode_size); if (r != EOK) ext4_fs_put_inode_ref(&inode_ref); else r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) { ext4_trans_abort(mp); goto Finish; } else ext4_trans_stop(mp); } if (inode_size > new_size) { inode_size = new_size; ext4_trans_start(mp); r = ext4_fs_get_inode_ref(fs, index, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); goto Finish; } r = ext4_fs_truncate_inode(&inode_ref, inode_size); if (r != EOK) ext4_fs_put_inode_ref(&inode_ref); else r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); } Finish: if (has_trans) ext4_trans_start(mp); return r; } static int ext4_trunc_dir(struct ext4_mountpoint *mp, struct ext4_inode_ref *parent, struct ext4_inode_ref *dir) { int r = EOK; bool is_dir = ext4_inode_is_type(&mp->fs.sb, dir->inode, EXT4_INODE_MODE_DIRECTORY); uint32_t block_size = ext4_sb_get_block_size(&mp->fs.sb); if (!is_dir) return EINVAL; #if CONFIG_DIR_INDEX_ENABLE /* Initialize directory index if supported */ if (ext4_sb_feature_com(&mp->fs.sb, EXT4_FCOM_DIR_INDEX)) { r = ext4_dir_dx_init(dir, parent); if (r != EOK) return r; r = ext4_trunc_inode(mp, dir->index, EXT4_DIR_DX_INIT_BCNT * block_size); if (r != EOK) return r; } else #endif { r = ext4_trunc_inode(mp, dir->index, block_size); if (r != EOK) return r; } return ext4_fs_truncate_inode(dir, 0); } /* * NOTICE: if filetype is equal to EXT4_DIRENTRY_UNKNOWN, * any filetype of the target dir entry will be accepted. */ static int ext4_generic_open2(ext4_file *f, const char *path, int flags, int ftype, uint32_t *parent_inode, uint32_t *name_off) { bool is_goal = false; uint32_t imode = EXT4_INODE_MODE_DIRECTORY; uint32_t next_inode; int r; int len; struct ext4_mountpoint *mp = ext4_get_mount(path); struct ext4_dir_search_result result; struct ext4_inode_ref ref; f->mp = 0; if (!mp) return ENOENT; struct ext4_fs *const fs = &mp->fs; struct ext4_sblock *const sb = &mp->fs.sb; if (fs->read_only && flags & O_CREAT) return EROFS; f->flags = flags; /*Skip mount point*/ path += strlen(mp->name); if (name_off) *name_off = strlen(mp->name); /*Load root*/ r = ext4_fs_get_inode_ref(fs, EXT4_INODE_ROOT_INDEX, &ref); if (r != EOK) return r; if (parent_inode) *parent_inode = ref.index; if (flags & O_CREAT) ext4_trans_start(mp); len = ext4_path_check(path, &is_goal); while (1) { len = ext4_path_check(path, &is_goal); if (!len) { /*If root open was request.*/ if (ftype == EXT4_DE_DIR || ftype == EXT4_DE_UNKNOWN) if (is_goal) break; r = ENOENT; break; } r = ext4_dir_find_entry(&result, &ref, path, len); if (r != EOK) { /*Destroy last result*/ ext4_dir_destroy_result(&ref, &result); if (r != ENOENT) break; if (!(f->flags & O_CREAT)) break; /*O_CREAT allows create new entry*/ struct ext4_inode_ref child_ref; r = ext4_fs_alloc_inode(fs, &child_ref, is_goal ? ftype : EXT4_DE_DIR); if (r != EOK) break; /*Link with root dir.*/ r = ext4_link(mp, &ref, &child_ref, path, len, false); if (r != EOK) { /*Fail. Free new inode.*/ ext4_fs_free_inode(&child_ref); /*We do not want to write new inode. But block has to be released.*/ child_ref.dirty = false; ext4_fs_put_inode_ref(&child_ref); break; } ext4_fs_put_inode_ref(&child_ref); continue; } if (parent_inode) *parent_inode = ref.index; next_inode = ext4_dir_en_get_inode(result.dentry); if (ext4_sb_feature_incom(sb, EXT4_FINCOM_FILETYPE)) { uint8_t t; t = ext4_dir_en_get_inode_type(sb, result.dentry); imode = ext4_fs_correspond_inode_mode(t); } else { struct ext4_inode_ref child_ref; r = ext4_fs_get_inode_ref(fs, next_inode, &child_ref); if (r != EOK) break; imode = ext4_inode_type(sb, child_ref.inode); ext4_fs_put_inode_ref(&child_ref); } r = ext4_dir_destroy_result(&ref, &result); if (r != EOK) break; /*If expected file error*/ if (imode != EXT4_INODE_MODE_DIRECTORY && !is_goal) { r = ENOENT; break; } if (ftype != EXT4_DE_UNKNOWN) { bool df = imode != ext4_fs_correspond_inode_mode(ftype); if (df && is_goal) { r = ENOENT; break; } } r = ext4_fs_put_inode_ref(&ref); if (r != EOK) break; r = ext4_fs_get_inode_ref(fs, next_inode, &ref); if (r != EOK) break; if (is_goal) break; path += len + 1; if (name_off) *name_off += len + 1; }; if (r != EOK) { ext4_fs_put_inode_ref(&ref); return r; } if (is_goal) { if ((f->flags & O_TRUNC) && (imode == EXT4_INODE_MODE_FILE)) { r = ext4_trunc_inode(mp, ref.index, 0); if (r != EOK) { ext4_fs_put_inode_ref(&ref); return r; } } f->mp = mp; f->fsize = ext4_inode_get_size(sb, ref.inode); f->inode = ref.index; f->fpos = 0; if (f->flags & O_APPEND) f->fpos = f->fsize; } r = ext4_fs_put_inode_ref(&ref); if (flags & O_CREAT) { if (r == EOK) ext4_trans_stop(mp); else ext4_trans_abort(mp); } return r; } /****************************************************************************/ static int ext4_generic_open(ext4_file *f, const char *path, const char *flags, bool file_expect, uint32_t *parent_inode, uint32_t *name_off) { uint32_t iflags; int filetype; if (ext4_parse_flags(flags, &iflags) == false) return EINVAL; if (file_expect == true) filetype = EXT4_DE_REG_FILE; else filetype = EXT4_DE_DIR; return ext4_generic_open2(f, path, iflags, filetype, parent_inode, name_off); } static int ext4_create_hardlink(const char *path, struct ext4_inode_ref *child_ref, bool rename) { bool is_goal = false; uint32_t inode_mode = EXT4_INODE_MODE_DIRECTORY; uint32_t next_inode; int r; int len; struct ext4_mountpoint *mp = ext4_get_mount(path); struct ext4_dir_search_result result; struct ext4_inode_ref ref; if (!mp) return ENOENT; struct ext4_fs *const fs = &mp->fs; struct ext4_sblock *const sb = &mp->fs.sb; /*Skip mount point*/ path += strlen(mp->name); /*Load root*/ r = ext4_fs_get_inode_ref(fs, EXT4_INODE_ROOT_INDEX, &ref); if (r != EOK) return r; len = ext4_path_check(path, &is_goal); while (1) { len = ext4_path_check(path, &is_goal); if (!len) { /*If root open was request.*/ r = is_goal ? EINVAL : ENOENT; break; } r = ext4_dir_find_entry(&result, &ref, path, len); if (r != EOK) { /*Destroy last result*/ ext4_dir_destroy_result(&ref, &result); if (r != ENOENT || !is_goal) break; /*Link with root dir.*/ r = ext4_link(mp, &ref, child_ref, path, len, rename); break; } else if (r == EOK && is_goal) { /*Destroy last result*/ ext4_dir_destroy_result(&ref, &result); r = EEXIST; break; } next_inode = result.dentry->inode; if (ext4_sb_feature_incom(sb, EXT4_FINCOM_FILETYPE)) { uint8_t t; t = ext4_dir_en_get_inode_type(sb, result.dentry); inode_mode = ext4_fs_correspond_inode_mode(t); } else { struct ext4_inode_ref child_ref; r = ext4_fs_get_inode_ref(fs, next_inode, &child_ref); if (r != EOK) break; inode_mode = ext4_inode_type(sb, child_ref.inode); ext4_fs_put_inode_ref(&child_ref); } r = ext4_dir_destroy_result(&ref, &result); if (r != EOK) break; if (inode_mode != EXT4_INODE_MODE_DIRECTORY) { r = is_goal ? EEXIST : ENOENT; break; } r = ext4_fs_put_inode_ref(&ref); if (r != EOK) break; r = ext4_fs_get_inode_ref(fs, next_inode, &ref); if (r != EOK) break; if (is_goal) break; path += len + 1; }; if (r != EOK) { ext4_fs_put_inode_ref(&ref); return r; } r = ext4_fs_put_inode_ref(&ref); return r; } static int ext4_remove_orig_reference(const char *path, uint32_t name_off, struct ext4_inode_ref *parent_ref, struct ext4_inode_ref *child_ref) { bool is_goal; int r; int len; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; /*Set path*/ path += name_off; len = ext4_path_check(path, &is_goal); /* Remove entry from parent directory */ r = ext4_dir_remove_entry(parent_ref, path, len); if (r != EOK) goto Finish; if (ext4_inode_is_type(&mp->fs.sb, child_ref->inode, EXT4_INODE_MODE_DIRECTORY)) { ext4_fs_inode_links_count_dec(parent_ref); parent_ref->dirty = true; } Finish: return r; } int ext4_flink(const char *path, const char *hardlink_path) { int r; ext4_file f; uint32_t name_off; bool child_loaded = false; uint32_t parent_inode, child_inode; struct ext4_mountpoint *mp = ext4_get_mount(path); struct ext4_mountpoint *target_mp = ext4_get_mount(hardlink_path); struct ext4_inode_ref child_ref; if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; /* Will that happen? Anyway return EINVAL for such case. */ if (mp != target_mp) return EINVAL; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDONLY, EXT4_DE_UNKNOWN, &parent_inode, &name_off); if (r != EOK) goto Finish; child_inode = f.inode; ext4_fclose(&f); /*We have file to unlink. Load it.*/ r = ext4_fs_get_inode_ref(&mp->fs, child_inode, &child_ref); if (r != EOK) goto Finish; child_loaded = true; /* Creating hardlink for directory is not allowed. */ if (ext4_inode_is_type(&mp->fs.sb, child_ref.inode, EXT4_INODE_MODE_DIRECTORY)) { r = EINVAL; goto Finish; } r = ext4_create_hardlink(hardlink_path, &child_ref, false); Finish: if (child_loaded) ext4_fs_put_inode_ref(&child_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_frename(const char *path, const char *new_path) { int r; ext4_file f; uint32_t name_off; bool parent_loaded = false, child_loaded = false; uint32_t parent_inode, child_inode; struct ext4_mountpoint *mp = ext4_get_mount(path); struct ext4_inode_ref child_ref, parent_ref; if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDONLY, EXT4_DE_UNKNOWN, &parent_inode, &name_off); if (r != EOK) goto Finish; child_inode = f.inode; ext4_fclose(&f); /*Load parent*/ r = ext4_fs_get_inode_ref(&mp->fs, parent_inode, &parent_ref); if (r != EOK) goto Finish; parent_loaded = true; /*We have file to unlink. Load it.*/ r = ext4_fs_get_inode_ref(&mp->fs, child_inode, &child_ref); if (r != EOK) goto Finish; child_loaded = true; r = ext4_create_hardlink(new_path, &child_ref, true); if (r != EOK) goto Finish; r = ext4_remove_orig_reference(path, name_off, &parent_ref, &child_ref); if (r != EOK) goto Finish; Finish: if (parent_loaded) ext4_fs_put_inode_ref(&parent_ref); if (child_loaded) ext4_fs_put_inode_ref(&child_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } /****************************************************************************/ int ext4_get_sblock(const char *mount_point, struct ext4_sblock **sb) { struct ext4_mountpoint *mp = ext4_get_mount(mount_point); if (!mp) return ENOENT; *sb = &mp->fs.sb; return EOK; } int ext4_cache_write_back(const char *path, bool on) { struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; EXT4_MP_LOCK(mp); ext4_block_cache_write_back(mp->fs.bdev, on); EXT4_MP_UNLOCK(mp); return EOK; } int ext4_fremove(const char *path) { ext4_file f; uint32_t parent_inode; uint32_t name_off; bool is_goal; int r; int len; struct ext4_inode_ref child; struct ext4_inode_ref parent; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, &parent_inode, &name_off); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } /*Load parent*/ r = ext4_fs_get_inode_ref(&mp->fs, parent_inode, &parent); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } /*We have file to delete. Load it.*/ r = ext4_fs_get_inode_ref(&mp->fs, f.inode, &child); if (r != EOK) { ext4_fs_put_inode_ref(&parent); ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } /* We do not allow opening files here. */ if (ext4_inode_type(&mp->fs.sb, child.inode) == EXT4_INODE_MODE_DIRECTORY) { ext4_fs_put_inode_ref(&parent); ext4_fs_put_inode_ref(&child); ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } /*Link count will be zero, the inode should be freed. */ if (ext4_inode_get_links_cnt(child.inode) == 1) { ext4_block_cache_write_back(mp->fs.bdev, 1); r = ext4_trunc_inode(mp, child.index, 0); if (r != EOK) { ext4_fs_put_inode_ref(&parent); ext4_fs_put_inode_ref(&child); ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_block_cache_write_back(mp->fs.bdev, 0); } /*Set path*/ path += name_off; len = ext4_path_check(path, &is_goal); /*Unlink from parent*/ r = ext4_unlink(mp, &parent, &child, path, len); if (r != EOK) goto Finish; /*Link count is zero, the inode should be freed. */ if (!ext4_inode_get_links_cnt(child.inode)) { ext4_inode_set_del_time(child.inode, -1L); r = ext4_fs_free_inode(&child); if (r != EOK) goto Finish; } Finish: ext4_fs_put_inode_ref(&child); ext4_fs_put_inode_ref(&parent); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_fill_raw_inode(const char *path, uint32_t *ret_ino, struct ext4_inode *inode) { int r; ext4_file f; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); uint32_t ino; if (!mp) return ENOENT; EXT4_MP_LOCK(mp); r = ext4_generic_open2(&f, path, O_RDONLY, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; ext4_fclose(&f); /*Load parent*/ r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { EXT4_MP_UNLOCK(mp); return r; } memcpy(inode, inode_ref.inode, sizeof(struct ext4_inode)); ext4_fs_put_inode_ref(&inode_ref); EXT4_MP_UNLOCK(mp); if (ret_ino) *ret_ino = ino; return r; } int ext4_fopen(ext4_file *f, const char *path, const char *flags) { struct ext4_mountpoint *mp = ext4_get_mount(path); int r; if (!mp) return ENOENT; EXT4_MP_LOCK(mp); ext4_block_cache_write_back(mp->fs.bdev, 1); r = ext4_generic_open(f, path, flags, true, 0, 0); ext4_block_cache_write_back(mp->fs.bdev, 0); EXT4_MP_UNLOCK(mp); return r; } int ext4_fopen2(ext4_file *f, const char *path, int flags) { struct ext4_mountpoint *mp = ext4_get_mount(path); int r; int filetype; if (!mp) return ENOENT; filetype = EXT4_DE_REG_FILE; EXT4_MP_LOCK(mp); ext4_block_cache_write_back(mp->fs.bdev, 1); r = ext4_generic_open2(f, path, flags, filetype, NULL, NULL); ext4_block_cache_write_back(mp->fs.bdev, 0); EXT4_MP_UNLOCK(mp); return r; } int ext4_fclose(ext4_file *f) { ext4_assert(f && f->mp); f->mp = 0; f->flags = 0; f->inode = 0; f->fpos = f->fsize = 0; return EOK; } static int ext4_ftruncate_no_lock(ext4_file *f, uint64_t size) { struct ext4_inode_ref ref; int r; r = ext4_fs_get_inode_ref(&f->mp->fs, f->inode, &ref); if (r != EOK) { EXT4_MP_UNLOCK(f->mp); return r; } /*Sync file size*/ f->fsize = ext4_inode_get_size(&f->mp->fs.sb, ref.inode); if (f->fsize <= size) { r = EOK; goto Finish; } /*Start write back cache mode.*/ r = ext4_block_cache_write_back(f->mp->fs.bdev, 1); if (r != EOK) goto Finish; r = ext4_trunc_inode(f->mp, ref.index, size); if (r != EOK) goto Finish; f->fsize = size; if (f->fpos > size) f->fpos = size; /*Stop write back cache mode*/ ext4_block_cache_write_back(f->mp->fs.bdev, 0); if (r != EOK) goto Finish; Finish: ext4_fs_put_inode_ref(&ref); return r; } int ext4_ftruncate(ext4_file *f, uint64_t size) { int r; ext4_assert(f && f->mp); if (f->mp->fs.read_only) return EROFS; if (f->flags & O_RDONLY) return EPERM; EXT4_MP_LOCK(f->mp); ext4_trans_start(f->mp); r = ext4_ftruncate_no_lock(f, size); if (r != EOK) ext4_trans_abort(f->mp); else ext4_trans_stop(f->mp); EXT4_MP_UNLOCK(f->mp); return r; } int ext4_fread(ext4_file *f, void *buf, size_t size, size_t *rcnt) { uint32_t unalg; uint32_t iblock_idx; uint32_t iblock_last; uint32_t block_size; ext4_fsblk_t fblock; ext4_fsblk_t fblock_start; uint32_t fblock_count; uint8_t *u8_buf = buf; int r; struct ext4_inode_ref ref; ext4_assert(f && f->mp); if (f->flags & O_WRONLY) return EPERM; if (!size) return EOK; EXT4_MP_LOCK(f->mp); struct ext4_fs *const fs = &f->mp->fs; struct ext4_sblock *const sb = &f->mp->fs.sb; if (rcnt) *rcnt = 0; r = ext4_fs_get_inode_ref(fs, f->inode, &ref); if (r != EOK) { EXT4_MP_UNLOCK(f->mp); return r; } /*Sync file size*/ f->fsize = ext4_inode_get_size(sb, ref.inode); block_size = ext4_sb_get_block_size(sb); size = ((uint64_t)size > (f->fsize - f->fpos)) ? ((size_t)(f->fsize - f->fpos)) : size; iblock_idx = (uint32_t)((f->fpos) / block_size); iblock_last = (uint32_t)((f->fpos + size) / block_size); unalg = (f->fpos) % block_size; /*If the size of symlink is smaller than 60 bytes*/ bool softlink; softlink = ext4_inode_is_type(sb, ref.inode, EXT4_INODE_MODE_SOFTLINK); if (softlink && f->fsize < sizeof(ref.inode->blocks) && !ext4_inode_get_blocks_count(sb, ref.inode)) { char *content = (char *)ref.inode->blocks; if (f->fpos < f->fsize) { size_t len = size; if (unalg + size > (uint32_t)f->fsize) len = (uint32_t)f->fsize - unalg; memcpy(buf, content + unalg, len); if (rcnt) *rcnt = len; } r = EOK; goto Finish; } if (unalg) { size_t len = size; if (size > (block_size - unalg)) len = block_size - unalg; r = ext4_fs_get_inode_dblk_idx(&ref, iblock_idx, &fblock, true); if (r != EOK) goto Finish; /* Do we get an unwritten range? */ if (fblock != 0) { uint64_t off = fblock * block_size + unalg; r = ext4_block_readbytes(f->mp->fs.bdev, off, u8_buf, len); if (r != EOK) goto Finish; } else { /* Yes, we do. */ memset(u8_buf, 0, len); } u8_buf += len; size -= len; f->fpos += len; if (rcnt) *rcnt += len; iblock_idx++; } fblock_start = 0; fblock_count = 0; while (size >= block_size) { while (iblock_idx < iblock_last) { r = ext4_fs_get_inode_dblk_idx(&ref, iblock_idx, &fblock, true); if (r != EOK) goto Finish; iblock_idx++; if (!fblock_start) fblock_start = fblock; if ((fblock_start + fblock_count) != fblock) break; fblock_count++; } r = ext4_blocks_get_direct(f->mp->fs.bdev, u8_buf, fblock_start, fblock_count); if (r != EOK) goto Finish; size -= block_size * fblock_count; u8_buf += block_size * fblock_count; f->fpos += block_size * fblock_count; if (rcnt) *rcnt += block_size * fblock_count; fblock_start = fblock; fblock_count = 1; } if (size) { uint64_t off; r = ext4_fs_get_inode_dblk_idx(&ref, iblock_idx, &fblock, true); if (r != EOK) goto Finish; off = fblock * block_size; r = ext4_block_readbytes(f->mp->fs.bdev, off, u8_buf, size); if (r != EOK) goto Finish; f->fpos += size; if (rcnt) *rcnt += size; } Finish: ext4_fs_put_inode_ref(&ref); EXT4_MP_UNLOCK(f->mp); return r; } int ext4_fwrite(ext4_file *f, const void *buf, size_t size, size_t *wcnt) { uint32_t unalg; uint32_t iblk_idx; uint32_t iblock_last; uint32_t ifile_blocks; uint32_t block_size; uint32_t fblock_count; ext4_fsblk_t fblk; ext4_fsblk_t fblock_start; struct ext4_inode_ref ref; const uint8_t *u8_buf = buf; int r, rr = EOK; ext4_assert(f && f->mp); if (f->mp->fs.read_only) return EROFS; if (f->flags & O_RDONLY) return EPERM; if (!size) return EOK; EXT4_MP_LOCK(f->mp); ext4_trans_start(f->mp); struct ext4_fs *const fs = &f->mp->fs; struct ext4_sblock *const sb = &f->mp->fs.sb; if (wcnt) *wcnt = 0; r = ext4_fs_get_inode_ref(fs, f->inode, &ref); if (r != EOK) { ext4_trans_abort(f->mp); EXT4_MP_UNLOCK(f->mp); return r; } /*Sync file size*/ f->fsize = ext4_inode_get_size(sb, ref.inode); block_size = ext4_sb_get_block_size(sb); iblock_last = (uint32_t)((f->fpos + size) / block_size); iblk_idx = (uint32_t)(f->fpos / block_size); ifile_blocks = (uint32_t)((f->fsize + block_size - 1) / block_size); unalg = (f->fpos) % block_size; if (unalg) { size_t len = size; uint64_t off; if (size > (block_size - unalg)) len = block_size - unalg; r = ext4_fs_init_inode_dblk_idx(&ref, iblk_idx, &fblk); if (r != EOK) goto Finish; off = fblk * block_size + unalg; r = ext4_block_writebytes(f->mp->fs.bdev, off, u8_buf, len); if (r != EOK) goto Finish; u8_buf += len; size -= len; f->fpos += len; if (wcnt) *wcnt += len; iblk_idx++; } /*Start write back cache mode.*/ r = ext4_block_cache_write_back(f->mp->fs.bdev, 1); if (r != EOK) goto Finish; fblock_start = 0; fblock_count = 0; while (size >= block_size) { while (iblk_idx < iblock_last) { if (iblk_idx < ifile_blocks) { r = ext4_fs_init_inode_dblk_idx(&ref, iblk_idx, &fblk); if (r != EOK) goto Finish; } else { rr = ext4_fs_append_inode_dblk(&ref, &fblk, &iblk_idx); if (rr != EOK) { /* Unable to append more blocks. But * some block might be allocated already * */ break; } } iblk_idx++; if (!fblock_start) { fblock_start = fblk; } if ((fblock_start + fblock_count) != fblk) break; fblock_count++; } r = ext4_blocks_set_direct(f->mp->fs.bdev, u8_buf, fblock_start, fblock_count); if (r != EOK) break; size -= block_size * fblock_count; u8_buf += block_size * fblock_count; f->fpos += block_size * fblock_count; if (wcnt) *wcnt += block_size * fblock_count; fblock_start = fblk; fblock_count = 1; if (rr != EOK) { /*ext4_fs_append_inode_block has failed and no * more blocks might be written. But node size * should be updated.*/ r = rr; goto out_fsize; } } /*Stop write back cache mode*/ ext4_block_cache_write_back(f->mp->fs.bdev, 0); if (r != EOK) goto Finish; if (size) { uint64_t off; if (iblk_idx < ifile_blocks) { r = ext4_fs_init_inode_dblk_idx(&ref, iblk_idx, &fblk); if (r != EOK) goto Finish; } else { r = ext4_fs_append_inode_dblk(&ref, &fblk, &iblk_idx); if (r != EOK) /*Node size sholud be updated.*/ goto out_fsize; } off = fblk * block_size; r = ext4_block_writebytes(f->mp->fs.bdev, off, u8_buf, size); if (r != EOK) goto Finish; f->fpos += size; if (wcnt) *wcnt += size; } out_fsize: if (f->fpos > f->fsize) { f->fsize = f->fpos; ext4_inode_set_size(ref.inode, f->fsize); ref.dirty = true; } Finish: r = ext4_fs_put_inode_ref(&ref); if (r != EOK) ext4_trans_abort(f->mp); else ext4_trans_stop(f->mp); EXT4_MP_UNLOCK(f->mp); return r; } int ext4_fseek(ext4_file *f, uint64_t offset, uint32_t origin) { switch (origin) { case SEEK_SET: if (offset > f->fsize) return EINVAL; f->fpos = offset; return EOK; case SEEK_CUR: if ((offset + f->fpos) > f->fsize) return EINVAL; f->fpos += offset; return EOK; case SEEK_END: if (offset > f->fsize) return EINVAL; f->fpos = f->fsize - offset; return EOK; } return EINVAL; } uint64_t ext4_ftell(ext4_file *f) { return f->fpos; } uint64_t ext4_fsize(ext4_file *f) { return f->fsize; } int ext4_chmod(const char *path, uint32_t mode) { int r; uint32_t ino, orig_mode; ext4_file f; struct ext4_sblock *sb; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; sb = &mp->fs.sb; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } orig_mode = ext4_inode_get_mode(sb, inode_ref.inode); orig_mode &= ~0xFFF; orig_mode |= mode & 0xFFF; ext4_inode_set_mode(sb, inode_ref.inode, orig_mode); inode_ref.dirty = true; r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_chown(const char *path, uint32_t uid, uint32_t gid) { int r; ext4_file f; uint32_t ino; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_inode_set_uid(inode_ref.inode, uid); ext4_inode_set_gid(inode_ref.inode, gid); inode_ref.dirty = true; r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_file_set_atime(const char *path, uint32_t atime) { int r; ext4_file f; uint32_t ino; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_inode_set_access_time(inode_ref.inode, atime); inode_ref.dirty = true; r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_file_set_mtime(const char *path, uint32_t mtime) { int r; ext4_file f; uint32_t ino; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_inode_set_modif_time(inode_ref.inode, mtime); inode_ref.dirty = true; r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_file_set_ctime(const char *path, uint32_t ctime) { int r; ext4_file f; uint32_t ino; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ino = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, ino, &inode_ref); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_inode_set_change_inode_time(inode_ref.inode, ctime); inode_ref.dirty = true; r = ext4_fs_put_inode_ref(&inode_ref); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } static int ext4_fsymlink_set(ext4_file *f, const void *buf, uint32_t size) { struct ext4_inode_ref ref; uint32_t sblock; ext4_fsblk_t fblock; uint32_t block_size; int r; ext4_assert(f && f->mp); if (!size) return EOK; r = ext4_fs_get_inode_ref(&f->mp->fs, f->inode, &ref); if (r != EOK) return r; /*Sync file size*/ block_size = ext4_sb_get_block_size(&f->mp->fs.sb); if (size > block_size) { r = EINVAL; goto Finish; } r = ext4_ftruncate_no_lock(f, 0); if (r != EOK) goto Finish; /*Start write back cache mode.*/ r = ext4_block_cache_write_back(f->mp->fs.bdev, 1); if (r != EOK) goto Finish; /*If the size of symlink is smaller than 60 bytes*/ if (size < sizeof(ref.inode->blocks)) { memset(ref.inode->blocks, 0, sizeof(ref.inode->blocks)); memcpy(ref.inode->blocks, buf, size); ext4_inode_clear_flag(ref.inode, EXT4_INODE_FLAG_EXTENTS); } else { ext4_fs_inode_blocks_init(&f->mp->fs, &ref); r = ext4_fs_append_inode_dblk(&ref, &fblock, &sblock); if (r != EOK) goto Finish; r = ext4_block_writebytes(f->mp->fs.bdev, 0, buf, size); if (r != EOK) goto Finish; } /*Stop write back cache mode*/ ext4_block_cache_write_back(f->mp->fs.bdev, 0); if (r != EOK) goto Finish; ext4_inode_set_size(ref.inode, size); ref.dirty = true; f->fsize = size; if (f->fpos > size) f->fpos = size; Finish: ext4_fs_put_inode_ref(&ref); return r; } int ext4_fsymlink(const char *target, const char *path) { struct ext4_mountpoint *mp = ext4_get_mount(path); int r; ext4_file f; int filetype; if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; filetype = EXT4_DE_SYMLINK; EXT4_MP_LOCK(mp); ext4_trans_start(mp); ext4_block_cache_write_back(mp->fs.bdev, 1); r = ext4_generic_open2(&f, path, O_RDWR|O_CREAT, filetype, NULL, NULL); if (r == EOK) r = ext4_fsymlink_set(&f, target, strlen(target)); else goto Finish; ext4_fclose(&f); Finish: ext4_block_cache_write_back(mp->fs.bdev, 0); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_readlink(const char *path, char *buf, size_t bufsize, size_t *rcnt) { struct ext4_mountpoint *mp = ext4_get_mount(path); int r; ext4_file f; int filetype; if (!mp) return ENOENT; if (!buf) return EINVAL; filetype = EXT4_DE_SYMLINK; EXT4_MP_LOCK(mp); ext4_block_cache_write_back(mp->fs.bdev, 1); r = ext4_generic_open2(&f, path, O_RDONLY, filetype, NULL, NULL); if (r == EOK) r = ext4_fread(&f, buf, bufsize, rcnt); else goto Finish; ext4_fclose(&f); Finish: ext4_block_cache_write_back(mp->fs.bdev, 0); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_setxattr(const char *path, const char *name, size_t name_len, const void *data, size_t data_size, bool replace) { bool found; int r = EOK; ext4_file f; uint32_t inode; uint8_t name_index; const char *dissected_name = NULL; size_t dissected_len = 0; struct ext4_xattr_ref xattr_ref; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; dissected_name = ext4_extract_xattr_name(name, name_len, &name_index, &dissected_len, &found); if (!found) return EINVAL; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) goto Finish; inode = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, inode, &inode_ref); if (r != EOK) goto Finish; r = ext4_fs_get_xattr_ref(&mp->fs, &inode_ref, &xattr_ref); if (r != EOK) { ext4_fs_put_inode_ref(&inode_ref); goto Finish; } r = ext4_fs_set_xattr(&xattr_ref, name_index, dissected_name, dissected_len, data, data_size, replace); ext4_fs_put_xattr_ref(&xattr_ref); ext4_fs_put_inode_ref(&inode_ref); Finish: if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_getxattr(const char *path, const char *name, size_t name_len, void *buf, size_t buf_size, size_t *data_size) { bool found; int r = EOK; ext4_file f; uint32_t inode; uint8_t name_index; const char *dissected_name = NULL; size_t dissected_len = 0; struct ext4_xattr_ref xattr_ref; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; dissected_name = ext4_extract_xattr_name(name, name_len, &name_index, &dissected_len, &found); if (!found) return EINVAL; EXT4_MP_LOCK(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) goto Finish; inode = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, inode, &inode_ref); if (r != EOK) goto Finish; r = ext4_fs_get_xattr_ref(&mp->fs, &inode_ref, &xattr_ref); if (r != EOK) { ext4_fs_put_inode_ref(&inode_ref); goto Finish; } r = ext4_fs_get_xattr(&xattr_ref, name_index, dissected_name, dissected_len, buf, buf_size, data_size); ext4_fs_put_xattr_ref(&xattr_ref); ext4_fs_put_inode_ref(&inode_ref); Finish: EXT4_MP_UNLOCK(mp); return r; } struct ext4_listxattr_iterator { char *list; char *list_ptr; size_t size; size_t ret_size; bool list_too_small; bool get_required_size; }; static int ext4_iterate_ea_list(struct ext4_xattr_ref *ref, struct ext4_xattr_item *item) { struct ext4_listxattr_iterator *lxi; lxi = ref->iter_arg; if (!lxi->get_required_size) { size_t plen; const char *prefix; prefix = ext4_get_xattr_name_prefix(item->name_index, &plen); if (lxi->ret_size + plen + item->name_len + 1 > lxi->size) { lxi->list_too_small = 1; return EXT4_XATTR_ITERATE_STOP; } if (prefix) { memcpy(lxi->list_ptr, prefix, plen); lxi->list_ptr += plen; lxi->ret_size += plen; } memcpy(lxi->list_ptr, item->name, item->name_len); lxi->list_ptr[item->name_len] = 0; lxi->list_ptr += item->name_len + 1; } lxi->ret_size += item->name_len + 1; return EXT4_XATTR_ITERATE_CONT; } int ext4_listxattr(const char *path, char *list, size_t size, size_t *ret_size) { int r = EOK; ext4_file f; uint32_t inode; struct ext4_xattr_ref xattr_ref; struct ext4_inode_ref inode_ref; struct ext4_listxattr_iterator lxi; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; lxi.list = list; lxi.list_ptr = list; lxi.size = size; lxi.ret_size = 0; lxi.list_too_small = false; lxi.get_required_size = (!size) ? true : false; EXT4_MP_LOCK(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) goto Finish; inode = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, inode, &inode_ref); if (r != EOK) goto Finish; r = ext4_fs_get_xattr_ref(&mp->fs, &inode_ref, &xattr_ref); if (r != EOK) { ext4_fs_put_inode_ref(&inode_ref); goto Finish; } xattr_ref.iter_arg = &lxi; ext4_fs_xattr_iterate(&xattr_ref, ext4_iterate_ea_list); if (lxi.list_too_small) r = ERANGE; if (r == EOK) { if (ret_size) *ret_size = lxi.ret_size; } ext4_fs_put_xattr_ref(&xattr_ref); ext4_fs_put_inode_ref(&inode_ref); Finish: EXT4_MP_UNLOCK(mp); return r; } int ext4_removexattr(const char *path, const char *name, size_t name_len) { bool found; int r = EOK; ext4_file f; uint32_t inode; uint8_t name_index; const char *dissected_name = NULL; size_t dissected_len = 0; struct ext4_xattr_ref xattr_ref; struct ext4_inode_ref inode_ref; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; dissected_name = ext4_extract_xattr_name(name, name_len, &name_index, &dissected_len, &found); if (!found) return EINVAL; EXT4_MP_LOCK(mp); ext4_trans_start(mp); r = ext4_generic_open2(&f, path, O_RDWR, EXT4_DE_UNKNOWN, NULL, NULL); if (r != EOK) goto Finish; inode = f.inode; ext4_fclose(&f); r = ext4_fs_get_inode_ref(&mp->fs, inode, &inode_ref); if (r != EOK) goto Finish; r = ext4_fs_get_xattr_ref(&mp->fs, &inode_ref, &xattr_ref); if (r != EOK) { ext4_fs_put_inode_ref(&inode_ref); goto Finish; } r = ext4_fs_remove_xattr(&xattr_ref, name_index, dissected_name, dissected_len); ext4_fs_put_xattr_ref(&xattr_ref); ext4_fs_put_inode_ref(&inode_ref); Finish: if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } /*********************************DIRECTORY OPERATION************************/ int ext4_dir_rm(const char *path) { int r; int len; ext4_file f; struct ext4_mountpoint *mp = ext4_get_mount(path); struct ext4_inode_ref act; struct ext4_inode_ref child; struct ext4_dir_iter it; uint32_t name_off; uint32_t inode_up; uint32_t inode_current; uint32_t depth = 1; bool has_children; bool is_goal; bool dir_end; if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); struct ext4_fs *const fs = &mp->fs; /*Check if exist.*/ r = ext4_generic_open(&f, path, "r", false, &inode_up, &name_off); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } path += name_off; len = ext4_path_check(path, &is_goal); inode_current = f.inode; ext4_block_cache_write_back(mp->fs.bdev, 1); do { uint64_t act_curr_pos = 0; has_children = false; dir_end = false; while (r == EOK && !has_children && !dir_end) { /*Load directory node.*/ r = ext4_fs_get_inode_ref(fs, inode_current, &act); if (r != EOK) { break; } /*Initialize iterator.*/ r = ext4_dir_iterator_init(&it, &act, act_curr_pos); if (r != EOK) { ext4_fs_put_inode_ref(&act); break; } if (!it.curr) { dir_end = true; goto End; } ext4_trans_start(mp); /*Get up directory inode when ".." entry*/ if ((it.curr->name_len == 2) && ext4_is_dots(it.curr->name, it.curr->name_len)) { inode_up = ext4_dir_en_get_inode(it.curr); } /*If directory or file entry, but not "." ".." entry*/ if (!ext4_is_dots(it.curr->name, it.curr->name_len)) { /*Get child inode reference do unlink * directory/file.*/ uint32_t cinode; uint32_t inode_type; cinode = ext4_dir_en_get_inode(it.curr); r = ext4_fs_get_inode_ref(fs, cinode, &child); if (r != EOK) goto End; /*If directory with no leaf children*/ r = ext4_has_children(&has_children, &child); if (r != EOK) { ext4_fs_put_inode_ref(&child); goto End; } if (has_children) { /*Has directory children. Go into this * directory.*/ inode_up = inode_current; inode_current = cinode; depth++; ext4_fs_put_inode_ref(&child); goto End; } inode_type = ext4_inode_type(&mp->fs.sb, child.inode); /* Truncate */ if (inode_type != EXT4_INODE_MODE_DIRECTORY) r = ext4_trunc_inode(mp, child.index, 0); else r = ext4_trunc_dir(mp, &act, &child); if (r != EOK) { ext4_fs_put_inode_ref(&child); goto End; } /*No children in child directory or file. Just * unlink.*/ r = ext4_unlink(f.mp, &act, &child, (char *)it.curr->name, it.curr->name_len); if (r != EOK) { ext4_fs_put_inode_ref(&child); goto End; } ext4_inode_set_del_time(child.inode, -1L); ext4_inode_set_links_cnt(child.inode, 0); child.dirty = true; r = ext4_fs_free_inode(&child); if (r != EOK) { ext4_fs_put_inode_ref(&child); goto End; } r = ext4_fs_put_inode_ref(&child); if (r != EOK) goto End; } r = ext4_dir_iterator_next(&it); if (r != EOK) goto End; act_curr_pos = it.curr_off; End: ext4_dir_iterator_fini(&it); if (r == EOK) r = ext4_fs_put_inode_ref(&act); else ext4_fs_put_inode_ref(&act); if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); } if (dir_end) { /*Directory iterator reached last entry*/ depth--; if (depth) inode_current = inode_up; } if (r != EOK) break; } while (depth); /*Last unlink*/ if (r == EOK && !depth) { /*Load parent.*/ struct ext4_inode_ref parent; r = ext4_fs_get_inode_ref(&f.mp->fs, inode_up, &parent); if (r != EOK) goto Finish; r = ext4_fs_get_inode_ref(&f.mp->fs, inode_current, &act); if (r != EOK) { ext4_fs_put_inode_ref(&act); goto Finish; } ext4_trans_start(mp); /* In this place all directories should be * unlinked. * Last unlink from root of current directory*/ r = ext4_unlink(f.mp, &parent, &act, (char *)path, len); if (r != EOK) { ext4_fs_put_inode_ref(&parent); ext4_fs_put_inode_ref(&act); goto Finish; } if (ext4_inode_get_links_cnt(act.inode) == 2) { ext4_inode_set_del_time(act.inode, -1L); ext4_inode_set_links_cnt(act.inode, 0); act.dirty = true; /*Truncate*/ r = ext4_trunc_dir(mp, &parent, &act); if (r != EOK) { ext4_fs_put_inode_ref(&parent); ext4_fs_put_inode_ref(&act); goto Finish; } r = ext4_fs_free_inode(&act); if (r != EOK) { ext4_fs_put_inode_ref(&parent); ext4_fs_put_inode_ref(&act); goto Finish; } } r = ext4_fs_put_inode_ref(&parent); if (r != EOK) goto Finish; r = ext4_fs_put_inode_ref(&act); Finish: if (r != EOK) ext4_trans_abort(mp); else ext4_trans_stop(mp); } ext4_block_cache_write_back(mp->fs.bdev, 0); EXT4_MP_UNLOCK(mp); return r; } int ext4_dir_mv(const char *path, const char *new_path) { return ext4_frename(path, new_path); } int ext4_dir_mk(const char *path) { int r; ext4_file f; struct ext4_mountpoint *mp = ext4_get_mount(path); if (!mp) return ENOENT; if (mp->fs.read_only) return EROFS; EXT4_MP_LOCK(mp); ext4_trans_start(mp); /*Check if exist.*/ r = ext4_generic_open(&f, path, "r", false, 0, 0); if (r == EOK) { /*Directory already created*/ ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } /*Create new dir*/ r = ext4_generic_open(&f, path, "w", false, 0, 0); if (r != EOK) { ext4_trans_abort(mp); EXT4_MP_UNLOCK(mp); return r; } ext4_trans_stop(mp); EXT4_MP_UNLOCK(mp); return r; } int ext4_dir_open(ext4_dir *d, const char *path) { struct ext4_mountpoint *mp = ext4_get_mount(path); int r; if (!mp) return ENOENT; EXT4_MP_LOCK(mp); r = ext4_generic_open(&d->f, path, "r", false, 0, 0); d->next_off = 0; EXT4_MP_UNLOCK(mp); return r; } int ext4_dir_close(ext4_dir *d) { return ext4_fclose(&d->f); } const ext4_direntry *ext4_dir_entry_next(ext4_dir *d) { #define EXT4_DIR_ENTRY_OFFSET_TERM (uint64_t)(-1) int r; ext4_direntry *de = 0; struct ext4_inode_ref dir; struct ext4_dir_iter it; EXT4_MP_LOCK(d->f.mp); if (d->next_off == EXT4_DIR_ENTRY_OFFSET_TERM) { EXT4_MP_UNLOCK(d->f.mp); return 0; } r = ext4_fs_get_inode_ref(&d->f.mp->fs, d->f.inode, &dir); if (r != EOK) { goto Finish; } r = ext4_dir_iterator_init(&it, &dir, d->next_off); if (r != EOK) { ext4_fs_put_inode_ref(&dir); goto Finish; } memcpy(&d->de, it.curr, sizeof(ext4_direntry)); de = &d->de; ext4_dir_iterator_next(&it); d->next_off = it.curr ? it.curr_off : EXT4_DIR_ENTRY_OFFSET_TERM; ext4_dir_iterator_fini(&it); ext4_fs_put_inode_ref(&dir); Finish: EXT4_MP_UNLOCK(d->f.mp); return de; } void ext4_dir_entry_rewind(ext4_dir *d) { d->next_off = 0; } /** * @} */