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-rw-r--r--fs/exofs/dir.c661
1 files changed, 0 insertions, 661 deletions
diff --git a/fs/exofs/dir.c b/fs/exofs/dir.c
deleted file mode 100644
index f0138674c1ed..000000000000
--- a/fs/exofs/dir.c
+++ /dev/null
@@ -1,661 +0,0 @@
-/*
- * Copyright (C) 2005, 2006
- * Avishay Traeger (avishay@gmail.com)
- * Copyright (C) 2008, 2009
- * Boaz Harrosh <ooo@electrozaur.com>
- *
- * Copyrights for code taken from ext2:
- * Copyright (C) 1992, 1993, 1994, 1995
- * Remy Card (card@masi.ibp.fr)
- * Laboratoire MASI - Institut Blaise Pascal
- * Universite Pierre et Marie Curie (Paris VI)
- * from
- * linux/fs/minix/inode.c
- * Copyright (C) 1991, 1992 Linus Torvalds
- *
- * This file is part of exofs.
- *
- * exofs 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. Since it is based on ext2, and the only
- * valid version of GPL for the Linux kernel is version 2, the only valid
- * version of GPL for exofs is version 2.
- *
- * exofs 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 exofs; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <linux/iversion.h>
-#include "exofs.h"
-
-static inline unsigned exofs_chunk_size(struct inode *inode)
-{
- return inode->i_sb->s_blocksize;
-}
-
-static inline void exofs_put_page(struct page *page)
-{
- kunmap(page);
- put_page(page);
-}
-
-static unsigned exofs_last_byte(struct inode *inode, unsigned long page_nr)
-{
- loff_t last_byte = inode->i_size;
-
- last_byte -= page_nr << PAGE_SHIFT;
- if (last_byte > PAGE_SIZE)
- last_byte = PAGE_SIZE;
- return last_byte;
-}
-
-static int exofs_commit_chunk(struct page *page, loff_t pos, unsigned len)
-{
- struct address_space *mapping = page->mapping;
- struct inode *dir = mapping->host;
- int err = 0;
-
- inode_inc_iversion(dir);
-
- if (!PageUptodate(page))
- SetPageUptodate(page);
-
- if (pos+len > dir->i_size) {
- i_size_write(dir, pos+len);
- mark_inode_dirty(dir);
- }
- set_page_dirty(page);
-
- if (IS_DIRSYNC(dir))
- err = write_one_page(page);
- else
- unlock_page(page);
-
- return err;
-}
-
-static bool exofs_check_page(struct page *page)
-{
- struct inode *dir = page->mapping->host;
- unsigned chunk_size = exofs_chunk_size(dir);
- char *kaddr = page_address(page);
- unsigned offs, rec_len;
- unsigned limit = PAGE_SIZE;
- struct exofs_dir_entry *p;
- char *error;
-
- /* if the page is the last one in the directory */
- if ((dir->i_size >> PAGE_SHIFT) == page->index) {
- limit = dir->i_size & ~PAGE_MASK;
- if (limit & (chunk_size - 1))
- goto Ebadsize;
- if (!limit)
- goto out;
- }
- for (offs = 0; offs <= limit - EXOFS_DIR_REC_LEN(1); offs += rec_len) {
- p = (struct exofs_dir_entry *)(kaddr + offs);
- rec_len = le16_to_cpu(p->rec_len);
-
- if (rec_len < EXOFS_DIR_REC_LEN(1))
- goto Eshort;
- if (rec_len & 3)
- goto Ealign;
- if (rec_len < EXOFS_DIR_REC_LEN(p->name_len))
- goto Enamelen;
- if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
- goto Espan;
- }
- if (offs != limit)
- goto Eend;
-out:
- SetPageChecked(page);
- return true;
-
-Ebadsize:
- EXOFS_ERR("ERROR [exofs_check_page]: "
- "size of directory(0x%lx) is not a multiple of chunk size\n",
- dir->i_ino
- );
- goto fail;
-Eshort:
- error = "rec_len is smaller than minimal";
- goto bad_entry;
-Ealign:
- error = "unaligned directory entry";
- goto bad_entry;
-Enamelen:
- error = "rec_len is too small for name_len";
- goto bad_entry;
-Espan:
- error = "directory entry across blocks";
- goto bad_entry;
-bad_entry:
- EXOFS_ERR(
- "ERROR [exofs_check_page]: bad entry in directory(0x%lx): %s - "
- "offset=%lu, inode=0x%llx, rec_len=%d, name_len=%d\n",
- dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs,
- _LLU(le64_to_cpu(p->inode_no)),
- rec_len, p->name_len);
- goto fail;
-Eend:
- p = (struct exofs_dir_entry *)(kaddr + offs);
- EXOFS_ERR("ERROR [exofs_check_page]: "
- "entry in directory(0x%lx) spans the page boundary"
- "offset=%lu, inode=0x%llx\n",
- dir->i_ino, (page->index<<PAGE_SHIFT)+offs,
- _LLU(le64_to_cpu(p->inode_no)));
-fail:
- SetPageError(page);
- return false;
-}
-
-static struct page *exofs_get_page(struct inode *dir, unsigned long n)
-{
- struct address_space *mapping = dir->i_mapping;
- struct page *page = read_mapping_page(mapping, n, NULL);
-
- if (!IS_ERR(page)) {
- kmap(page);
- if (unlikely(!PageChecked(page))) {
- if (PageError(page) || !exofs_check_page(page))
- goto fail;
- }
- }
- return page;
-
-fail:
- exofs_put_page(page);
- return ERR_PTR(-EIO);
-}
-
-static inline int exofs_match(int len, const unsigned char *name,
- struct exofs_dir_entry *de)
-{
- if (len != de->name_len)
- return 0;
- if (!de->inode_no)
- return 0;
- return !memcmp(name, de->name, len);
-}
-
-static inline
-struct exofs_dir_entry *exofs_next_entry(struct exofs_dir_entry *p)
-{
- return (struct exofs_dir_entry *)((char *)p + le16_to_cpu(p->rec_len));
-}
-
-static inline unsigned
-exofs_validate_entry(char *base, unsigned offset, unsigned mask)
-{
- struct exofs_dir_entry *de = (struct exofs_dir_entry *)(base + offset);
- struct exofs_dir_entry *p =
- (struct exofs_dir_entry *)(base + (offset&mask));
- while ((char *)p < (char *)de) {
- if (p->rec_len == 0)
- break;
- p = exofs_next_entry(p);
- }
- return (char *)p - base;
-}
-
-static unsigned char exofs_filetype_table[EXOFS_FT_MAX] = {
- [EXOFS_FT_UNKNOWN] = DT_UNKNOWN,
- [EXOFS_FT_REG_FILE] = DT_REG,
- [EXOFS_FT_DIR] = DT_DIR,
- [EXOFS_FT_CHRDEV] = DT_CHR,
- [EXOFS_FT_BLKDEV] = DT_BLK,
- [EXOFS_FT_FIFO] = DT_FIFO,
- [EXOFS_FT_SOCK] = DT_SOCK,
- [EXOFS_FT_SYMLINK] = DT_LNK,
-};
-
-#define S_SHIFT 12
-static unsigned char exofs_type_by_mode[S_IFMT >> S_SHIFT] = {
- [S_IFREG >> S_SHIFT] = EXOFS_FT_REG_FILE,
- [S_IFDIR >> S_SHIFT] = EXOFS_FT_DIR,
- [S_IFCHR >> S_SHIFT] = EXOFS_FT_CHRDEV,
- [S_IFBLK >> S_SHIFT] = EXOFS_FT_BLKDEV,
- [S_IFIFO >> S_SHIFT] = EXOFS_FT_FIFO,
- [S_IFSOCK >> S_SHIFT] = EXOFS_FT_SOCK,
- [S_IFLNK >> S_SHIFT] = EXOFS_FT_SYMLINK,
-};
-
-static inline
-void exofs_set_de_type(struct exofs_dir_entry *de, struct inode *inode)
-{
- umode_t mode = inode->i_mode;
- de->file_type = exofs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
-}
-
-static int
-exofs_readdir(struct file *file, struct dir_context *ctx)
-{
- loff_t pos = ctx->pos;
- struct inode *inode = file_inode(file);
- unsigned int offset = pos & ~PAGE_MASK;
- unsigned long n = pos >> PAGE_SHIFT;
- unsigned long npages = dir_pages(inode);
- unsigned chunk_mask = ~(exofs_chunk_size(inode)-1);
- bool need_revalidate = !inode_eq_iversion(inode, file->f_version);
-
- if (pos > inode->i_size - EXOFS_DIR_REC_LEN(1))
- return 0;
-
- for ( ; n < npages; n++, offset = 0) {
- char *kaddr, *limit;
- struct exofs_dir_entry *de;
- struct page *page = exofs_get_page(inode, n);
-
- if (IS_ERR(page)) {
- EXOFS_ERR("ERROR: bad page in directory(0x%lx)\n",
- inode->i_ino);
- ctx->pos += PAGE_SIZE - offset;
- return PTR_ERR(page);
- }
- kaddr = page_address(page);
- if (unlikely(need_revalidate)) {
- if (offset) {
- offset = exofs_validate_entry(kaddr, offset,
- chunk_mask);
- ctx->pos = (n<<PAGE_SHIFT) + offset;
- }
- file->f_version = inode_query_iversion(inode);
- need_revalidate = false;
- }
- de = (struct exofs_dir_entry *)(kaddr + offset);
- limit = kaddr + exofs_last_byte(inode, n) -
- EXOFS_DIR_REC_LEN(1);
- for (; (char *)de <= limit; de = exofs_next_entry(de)) {
- if (de->rec_len == 0) {
- EXOFS_ERR("ERROR: "
- "zero-length entry in directory(0x%lx)\n",
- inode->i_ino);
- exofs_put_page(page);
- return -EIO;
- }
- if (de->inode_no) {
- unsigned char t;
-
- if (de->file_type < EXOFS_FT_MAX)
- t = exofs_filetype_table[de->file_type];
- else
- t = DT_UNKNOWN;
-
- if (!dir_emit(ctx, de->name, de->name_len,
- le64_to_cpu(de->inode_no),
- t)) {
- exofs_put_page(page);
- return 0;
- }
- }
- ctx->pos += le16_to_cpu(de->rec_len);
- }
- exofs_put_page(page);
- }
- return 0;
-}
-
-struct exofs_dir_entry *exofs_find_entry(struct inode *dir,
- struct dentry *dentry, struct page **res_page)
-{
- const unsigned char *name = dentry->d_name.name;
- int namelen = dentry->d_name.len;
- unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
- unsigned long start, n;
- unsigned long npages = dir_pages(dir);
- struct page *page = NULL;
- struct exofs_i_info *oi = exofs_i(dir);
- struct exofs_dir_entry *de;
-
- if (npages == 0)
- goto out;
-
- *res_page = NULL;
-
- start = oi->i_dir_start_lookup;
- if (start >= npages)
- start = 0;
- n = start;
- do {
- char *kaddr;
- page = exofs_get_page(dir, n);
- if (!IS_ERR(page)) {
- kaddr = page_address(page);
- de = (struct exofs_dir_entry *) kaddr;
- kaddr += exofs_last_byte(dir, n) - reclen;
- while ((char *) de <= kaddr) {
- if (de->rec_len == 0) {
- EXOFS_ERR("ERROR: zero-length entry in "
- "directory(0x%lx)\n",
- dir->i_ino);
- exofs_put_page(page);
- goto out;
- }
- if (exofs_match(namelen, name, de))
- goto found;
- de = exofs_next_entry(de);
- }
- exofs_put_page(page);
- }
- if (++n >= npages)
- n = 0;
- } while (n != start);
-out:
- return NULL;
-
-found:
- *res_page = page;
- oi->i_dir_start_lookup = n;
- return de;
-}
-
-struct exofs_dir_entry *exofs_dotdot(struct inode *dir, struct page **p)
-{
- struct page *page = exofs_get_page(dir, 0);
- struct exofs_dir_entry *de = NULL;
-
- if (!IS_ERR(page)) {
- de = exofs_next_entry(
- (struct exofs_dir_entry *)page_address(page));
- *p = page;
- }
- return de;
-}
-
-ino_t exofs_parent_ino(struct dentry *child)
-{
- struct page *page;
- struct exofs_dir_entry *de;
- ino_t ino;
-
- de = exofs_dotdot(d_inode(child), &page);
- if (!de)
- return 0;
-
- ino = le64_to_cpu(de->inode_no);
- exofs_put_page(page);
- return ino;
-}
-
-ino_t exofs_inode_by_name(struct inode *dir, struct dentry *dentry)
-{
- ino_t res = 0;
- struct exofs_dir_entry *de;
- struct page *page;
-
- de = exofs_find_entry(dir, dentry, &page);
- if (de) {
- res = le64_to_cpu(de->inode_no);
- exofs_put_page(page);
- }
- return res;
-}
-
-int exofs_set_link(struct inode *dir, struct exofs_dir_entry *de,
- struct page *page, struct inode *inode)
-{
- loff_t pos = page_offset(page) +
- (char *) de - (char *) page_address(page);
- unsigned len = le16_to_cpu(de->rec_len);
- int err;
-
- lock_page(page);
- err = exofs_write_begin(NULL, page->mapping, pos, len, 0, &page, NULL);
- if (err)
- EXOFS_ERR("exofs_set_link: exofs_write_begin FAILED => %d\n",
- err);
-
- de->inode_no = cpu_to_le64(inode->i_ino);
- exofs_set_de_type(de, inode);
- if (likely(!err))
- err = exofs_commit_chunk(page, pos, len);
- exofs_put_page(page);
- dir->i_mtime = dir->i_ctime = current_time(dir);
- mark_inode_dirty(dir);
- return err;
-}
-
-int exofs_add_link(struct dentry *dentry, struct inode *inode)
-{
- struct inode *dir = d_inode(dentry->d_parent);
- const unsigned char *name = dentry->d_name.name;
- int namelen = dentry->d_name.len;
- unsigned chunk_size = exofs_chunk_size(dir);
- unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
- unsigned short rec_len, name_len;
- struct page *page = NULL;
- struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
- struct exofs_dir_entry *de;
- unsigned long npages = dir_pages(dir);
- unsigned long n;
- char *kaddr;
- loff_t pos;
- int err;
-
- for (n = 0; n <= npages; n++) {
- char *dir_end;
-
- page = exofs_get_page(dir, n);
- err = PTR_ERR(page);
- if (IS_ERR(page))
- goto out;
- lock_page(page);
- kaddr = page_address(page);
- dir_end = kaddr + exofs_last_byte(dir, n);
- de = (struct exofs_dir_entry *)kaddr;
- kaddr += PAGE_SIZE - reclen;
- while ((char *)de <= kaddr) {
- if ((char *)de == dir_end) {
- name_len = 0;
- rec_len = chunk_size;
- de->rec_len = cpu_to_le16(chunk_size);
- de->inode_no = 0;
- goto got_it;
- }
- if (de->rec_len == 0) {
- EXOFS_ERR("ERROR: exofs_add_link: "
- "zero-length entry in directory(0x%lx)\n",
- inode->i_ino);
- err = -EIO;
- goto out_unlock;
- }
- err = -EEXIST;
- if (exofs_match(namelen, name, de))
- goto out_unlock;
- name_len = EXOFS_DIR_REC_LEN(de->name_len);
- rec_len = le16_to_cpu(de->rec_len);
- if (!de->inode_no && rec_len >= reclen)
- goto got_it;
- if (rec_len >= name_len + reclen)
- goto got_it;
- de = (struct exofs_dir_entry *) ((char *) de + rec_len);
- }
- unlock_page(page);
- exofs_put_page(page);
- }
-
- EXOFS_ERR("exofs_add_link: BAD dentry=%p or inode=0x%lx\n",
- dentry, inode->i_ino);
- return -EINVAL;
-
-got_it:
- pos = page_offset(page) +
- (char *)de - (char *)page_address(page);
- err = exofs_write_begin(NULL, page->mapping, pos, rec_len, 0,
- &page, NULL);
- if (err)
- goto out_unlock;
- if (de->inode_no) {
- struct exofs_dir_entry *de1 =
- (struct exofs_dir_entry *)((char *)de + name_len);
- de1->rec_len = cpu_to_le16(rec_len - name_len);
- de->rec_len = cpu_to_le16(name_len);
- de = de1;
- }
- de->name_len = namelen;
- memcpy(de->name, name, namelen);
- de->inode_no = cpu_to_le64(inode->i_ino);
- exofs_set_de_type(de, inode);
- err = exofs_commit_chunk(page, pos, rec_len);
- dir->i_mtime = dir->i_ctime = current_time(dir);
- mark_inode_dirty(dir);
- sbi->s_numfiles++;
-
-out_put:
- exofs_put_page(page);
-out:
- return err;
-out_unlock:
- unlock_page(page);
- goto out_put;
-}
-
-int exofs_delete_entry(struct exofs_dir_entry *dir, struct page *page)
-{
- struct address_space *mapping = page->mapping;
- struct inode *inode = mapping->host;
- struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
- char *kaddr = page_address(page);
- unsigned from = ((char *)dir - kaddr) & ~(exofs_chunk_size(inode)-1);
- unsigned to = ((char *)dir - kaddr) + le16_to_cpu(dir->rec_len);
- loff_t pos;
- struct exofs_dir_entry *pde = NULL;
- struct exofs_dir_entry *de = (struct exofs_dir_entry *) (kaddr + from);
- int err;
-
- while (de < dir) {
- if (de->rec_len == 0) {
- EXOFS_ERR("ERROR: exofs_delete_entry:"
- "zero-length entry in directory(0x%lx)\n",
- inode->i_ino);
- err = -EIO;
- goto out;
- }
- pde = de;
- de = exofs_next_entry(de);
- }
- if (pde)
- from = (char *)pde - (char *)page_address(page);
- pos = page_offset(page) + from;
- lock_page(page);
- err = exofs_write_begin(NULL, page->mapping, pos, to - from, 0,
- &page, NULL);
- if (err)
- EXOFS_ERR("exofs_delete_entry: exofs_write_begin FAILED => %d\n",
- err);
- if (pde)
- pde->rec_len = cpu_to_le16(to - from);
- dir->inode_no = 0;
- if (likely(!err))
- err = exofs_commit_chunk(page, pos, to - from);
- inode->i_ctime = inode->i_mtime = current_time(inode);
- mark_inode_dirty(inode);
- sbi->s_numfiles--;
-out:
- exofs_put_page(page);
- return err;
-}
-
-/* kept aligned on 4 bytes */
-#define THIS_DIR ".\0\0"
-#define PARENT_DIR "..\0"
-
-int exofs_make_empty(struct inode *inode, struct inode *parent)
-{
- struct address_space *mapping = inode->i_mapping;
- struct page *page = grab_cache_page(mapping, 0);
- unsigned chunk_size = exofs_chunk_size(inode);
- struct exofs_dir_entry *de;
- int err;
- void *kaddr;
-
- if (!page)
- return -ENOMEM;
-
- err = exofs_write_begin(NULL, page->mapping, 0, chunk_size, 0,
- &page, NULL);
- if (err) {
- unlock_page(page);
- goto fail;
- }
-
- kaddr = kmap_atomic(page);
- de = (struct exofs_dir_entry *)kaddr;
- de->name_len = 1;
- de->rec_len = cpu_to_le16(EXOFS_DIR_REC_LEN(1));
- memcpy(de->name, THIS_DIR, sizeof(THIS_DIR));
- de->inode_no = cpu_to_le64(inode->i_ino);
- exofs_set_de_type(de, inode);
-
- de = (struct exofs_dir_entry *)(kaddr + EXOFS_DIR_REC_LEN(1));
- de->name_len = 2;
- de->rec_len = cpu_to_le16(chunk_size - EXOFS_DIR_REC_LEN(1));
- de->inode_no = cpu_to_le64(parent->i_ino);
- memcpy(de->name, PARENT_DIR, sizeof(PARENT_DIR));
- exofs_set_de_type(de, inode);
- kunmap_atomic(kaddr);
- err = exofs_commit_chunk(page, 0, chunk_size);
-fail:
- put_page(page);
- return err;
-}
-
-int exofs_empty_dir(struct inode *inode)
-{
- struct page *page = NULL;
- unsigned long i, npages = dir_pages(inode);
-
- for (i = 0; i < npages; i++) {
- char *kaddr;
- struct exofs_dir_entry *de;
- page = exofs_get_page(inode, i);
-
- if (IS_ERR(page))
- continue;
-
- kaddr = page_address(page);
- de = (struct exofs_dir_entry *)kaddr;
- kaddr += exofs_last_byte(inode, i) - EXOFS_DIR_REC_LEN(1);
-
- while ((char *)de <= kaddr) {
- if (de->rec_len == 0) {
- EXOFS_ERR("ERROR: exofs_empty_dir: "
- "zero-length directory entry"
- "kaddr=%p, de=%p\n", kaddr, de);
- goto not_empty;
- }
- if (de->inode_no != 0) {
- /* check for . and .. */
- if (de->name[0] != '.')
- goto not_empty;
- if (de->name_len > 2)
- goto not_empty;
- if (de->name_len < 2) {
- if (le64_to_cpu(de->inode_no) !=
- inode->i_ino)
- goto not_empty;
- } else if (de->name[1] != '.')
- goto not_empty;
- }
- de = exofs_next_entry(de);
- }
- exofs_put_page(page);
- }
- return 1;
-
-not_empty:
- exofs_put_page(page);
- return 0;
-}
-
-const struct file_operations exofs_dir_operations = {
- .llseek = generic_file_llseek,
- .read = generic_read_dir,
- .iterate_shared = exofs_readdir,
-};
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-27 11:04:08 +0000