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-rw-r--r--fs/sysv/dir.c378
1 files changed, 0 insertions, 378 deletions
diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
deleted file mode 100644
index 639307e2ff8c..000000000000
--- a/fs/sysv/dir.c
+++ /dev/null
@@ -1,378 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * linux/fs/sysv/dir.c
- *
- * minix/dir.c
- * Copyright (C) 1991, 1992 Linus Torvalds
- *
- * coh/dir.c
- * Copyright (C) 1993 Pascal Haible, Bruno Haible
- *
- * sysv/dir.c
- * Copyright (C) 1993 Bruno Haible
- *
- * SystemV/Coherent directory handling functions
- */
-
-#include <linux/pagemap.h>
-#include <linux/highmem.h>
-#include <linux/swap.h>
-#include "sysv.h"
-
-static int sysv_readdir(struct file *, struct dir_context *);
-
-const struct file_operations sysv_dir_operations = {
- .llseek = generic_file_llseek,
- .read = generic_read_dir,
- .iterate_shared = sysv_readdir,
- .fsync = generic_file_fsync,
-};
-
-static void dir_commit_chunk(struct folio *folio, loff_t pos, unsigned len)
-{
- struct address_space *mapping = folio->mapping;
- struct inode *dir = mapping->host;
-
- block_write_end(NULL, mapping, pos, len, len, folio, NULL);
- if (pos+len > dir->i_size) {
- i_size_write(dir, pos+len);
- mark_inode_dirty(dir);
- }
- folio_unlock(folio);
-}
-
-static int sysv_handle_dirsync(struct inode *dir)
-{
- int err;
-
- err = filemap_write_and_wait(dir->i_mapping);
- if (!err)
- err = sync_inode_metadata(dir, 1);
- return err;
-}
-
-/*
- * Calls to dir_get_folio()/folio_release_kmap() must be nested according to the
- * rules documented in mm/highmem.rst.
- *
- * NOTE: sysv_find_entry() and sysv_dotdot() act as calls to dir_get_folio()
- * and must be treated accordingly for nesting purposes.
- */
-static void *dir_get_folio(struct inode *dir, unsigned long n,
- struct folio **foliop)
-{
- struct folio *folio = read_mapping_folio(dir->i_mapping, n, NULL);
-
- if (IS_ERR(folio))
- return ERR_CAST(folio);
- *foliop = folio;
- return kmap_local_folio(folio, 0);
-}
-
-static int sysv_readdir(struct file *file, struct dir_context *ctx)
-{
- unsigned long pos = ctx->pos;
- struct inode *inode = file_inode(file);
- struct super_block *sb = inode->i_sb;
- unsigned long npages = dir_pages(inode);
- unsigned offset;
- unsigned long n;
-
- ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
- if (pos >= inode->i_size)
- return 0;
-
- offset = pos & ~PAGE_MASK;
- n = pos >> PAGE_SHIFT;
-
- for ( ; n < npages; n++, offset = 0) {
- char *kaddr, *limit;
- struct sysv_dir_entry *de;
- struct folio *folio;
-
- kaddr = dir_get_folio(inode, n, &folio);
- if (IS_ERR(kaddr))
- continue;
- de = (struct sysv_dir_entry *)(kaddr+offset);
- limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE;
- for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) {
- char *name = de->name;
-
- if (!de->inode)
- continue;
-
- if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
- fs16_to_cpu(SYSV_SB(sb), de->inode),
- DT_UNKNOWN)) {
- folio_release_kmap(folio, kaddr);
- return 0;
- }
- }
- folio_release_kmap(folio, kaddr);
- }
- return 0;
-}
-
-/* compare strings: name[0..len-1] (not zero-terminated) and
- * buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
- */
-static inline int namecompare(int len, int maxlen,
- const char * name, const char * buffer)
-{
- if (len < maxlen && buffer[len])
- return 0;
- return !memcmp(name, buffer, len);
-}
-
-/*
- * sysv_find_entry()
- *
- * finds an entry in the specified directory with the wanted name.
- * It does NOT read the inode of the
- * entry - you'll have to do that yourself if you want to.
- *
- * On Success folio_release_kmap() should be called on *foliop.
- *
- * sysv_find_entry() acts as a call to dir_get_folio() and must be treated
- * accordingly for nesting purposes.
- */
-struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct folio **foliop)
-{
- const char * name = dentry->d_name.name;
- int namelen = dentry->d_name.len;
- struct inode * dir = d_inode(dentry->d_parent);
- unsigned long start, n;
- unsigned long npages = dir_pages(dir);
- struct sysv_dir_entry *de;
-
- start = SYSV_I(dir)->i_dir_start_lookup;
- if (start >= npages)
- start = 0;
- n = start;
-
- do {
- char *kaddr = dir_get_folio(dir, n, foliop);
-
- if (!IS_ERR(kaddr)) {
- de = (struct sysv_dir_entry *)kaddr;
- kaddr += folio_size(*foliop) - SYSV_DIRSIZE;
- for ( ; (char *) de <= kaddr ; de++) {
- if (!de->inode)
- continue;
- if (namecompare(namelen, SYSV_NAMELEN,
- name, de->name))
- goto found;
- }
- folio_release_kmap(*foliop, kaddr);
- }
-
- if (++n >= npages)
- n = 0;
- } while (n != start);
-
- return NULL;
-
-found:
- SYSV_I(dir)->i_dir_start_lookup = n;
- return de;
-}
-
-int sysv_add_link(struct dentry *dentry, struct inode *inode)
-{
- struct inode *dir = d_inode(dentry->d_parent);
- const char * name = dentry->d_name.name;
- int namelen = dentry->d_name.len;
- struct folio *folio = NULL;
- struct sysv_dir_entry * de;
- unsigned long npages = dir_pages(dir);
- unsigned long n;
- char *kaddr;
- loff_t pos;
- int err;
-
- /* We take care of directory expansion in the same loop */
- for (n = 0; n <= npages; n++) {
- kaddr = dir_get_folio(dir, n, &folio);
- if (IS_ERR(kaddr))
- return PTR_ERR(kaddr);
- de = (struct sysv_dir_entry *)kaddr;
- kaddr += PAGE_SIZE - SYSV_DIRSIZE;
- while ((char *)de <= kaddr) {
- if (!de->inode)
- goto got_it;
- err = -EEXIST;
- if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
- goto out_folio;
- de++;
- }
- folio_release_kmap(folio, kaddr);
- }
- BUG();
- return -EINVAL;
-
-got_it:
- pos = folio_pos(folio) + offset_in_folio(folio, de);
- folio_lock(folio);
- err = sysv_prepare_chunk(folio, pos, SYSV_DIRSIZE);
- if (err)
- goto out_unlock;
- memcpy (de->name, name, namelen);
- memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
- de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
- dir_commit_chunk(folio, pos, SYSV_DIRSIZE);
- inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
- mark_inode_dirty(dir);
- err = sysv_handle_dirsync(dir);
-out_folio:
- folio_release_kmap(folio, kaddr);
- return err;
-out_unlock:
- folio_unlock(folio);
- goto out_folio;
-}
-
-int sysv_delete_entry(struct sysv_dir_entry *de, struct folio *folio)
-{
- struct inode *inode = folio->mapping->host;
- loff_t pos = folio_pos(folio) + offset_in_folio(folio, de);
- int err;
-
- folio_lock(folio);
- err = sysv_prepare_chunk(folio, pos, SYSV_DIRSIZE);
- if (err) {
- folio_unlock(folio);
- return err;
- }
- de->inode = 0;
- dir_commit_chunk(folio, pos, SYSV_DIRSIZE);
- inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
- mark_inode_dirty(inode);
- return sysv_handle_dirsync(inode);
-}
-
-int sysv_make_empty(struct inode *inode, struct inode *dir)
-{
- struct folio *folio = filemap_grab_folio(inode->i_mapping, 0);
- struct sysv_dir_entry * de;
- char *kaddr;
- int err;
-
- if (IS_ERR(folio))
- return PTR_ERR(folio);
- err = sysv_prepare_chunk(folio, 0, 2 * SYSV_DIRSIZE);
- if (err) {
- folio_unlock(folio);
- goto fail;
- }
- kaddr = kmap_local_folio(folio, 0);
- memset(kaddr, 0, folio_size(folio));
-
- de = (struct sysv_dir_entry *)kaddr;
- de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
- strcpy(de->name,".");
- de++;
- de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino);
- strcpy(de->name,"..");
-
- kunmap_local(kaddr);
- dir_commit_chunk(folio, 0, 2 * SYSV_DIRSIZE);
- err = sysv_handle_dirsync(inode);
-fail:
- folio_put(folio);
- return err;
-}
-
-/*
- * routine to check that the specified directory is empty (for rmdir)
- */
-int sysv_empty_dir(struct inode * inode)
-{
- struct super_block *sb = inode->i_sb;
- struct folio *folio = NULL;
- unsigned long i, npages = dir_pages(inode);
- char *kaddr;
-
- for (i = 0; i < npages; i++) {
- struct sysv_dir_entry *de;
-
- kaddr = dir_get_folio(inode, i, &folio);
- if (IS_ERR(kaddr))
- continue;
-
- de = (struct sysv_dir_entry *)kaddr;
- kaddr += folio_size(folio) - SYSV_DIRSIZE;
-
- for ( ;(char *)de <= kaddr; de++) {
- if (!de->inode)
- continue;
- /* check for . and .. */
- if (de->name[0] != '.')
- goto not_empty;
- if (!de->name[1]) {
- if (de->inode == cpu_to_fs16(SYSV_SB(sb),
- inode->i_ino))
- continue;
- goto not_empty;
- }
- if (de->name[1] != '.' || de->name[2])
- goto not_empty;
- }
- folio_release_kmap(folio, kaddr);
- }
- return 1;
-
-not_empty:
- folio_release_kmap(folio, kaddr);
- return 0;
-}
-
-/* Releases the page */
-int sysv_set_link(struct sysv_dir_entry *de, struct folio *folio,
- struct inode *inode)
-{
- struct inode *dir = folio->mapping->host;
- loff_t pos = folio_pos(folio) + offset_in_folio(folio, de);
- int err;
-
- folio_lock(folio);
- err = sysv_prepare_chunk(folio, pos, SYSV_DIRSIZE);
- if (err) {
- folio_unlock(folio);
- return err;
- }
- de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
- dir_commit_chunk(folio, pos, SYSV_DIRSIZE);
- inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
- mark_inode_dirty(dir);
- return sysv_handle_dirsync(inode);
-}
-
-/*
- * Calls to dir_get_folio()/folio_release_kmap() must be nested according to the
- * rules documented in mm/highmem.rst.
- *
- * sysv_dotdot() acts as a call to dir_get_folio() and must be treated
- * accordingly for nesting purposes.
- */
-struct sysv_dir_entry *sysv_dotdot(struct inode *dir, struct folio **foliop)
-{
- struct sysv_dir_entry *de = dir_get_folio(dir, 0, foliop);
-
- if (IS_ERR(de))
- return NULL;
- /* ".." is the second directory entry */
- return de + 1;
-}
-
-ino_t sysv_inode_by_name(struct dentry *dentry)
-{
- struct folio *folio;
- struct sysv_dir_entry *de = sysv_find_entry (dentry, &folio);
- ino_t res = 0;
-
- if (de) {
- res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode);
- folio_release_kmap(folio, de);
- }
- return res;
-}