linux/fs/minix/dir.c
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

470 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/minix/dir.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* minix directory handling functions
*
* Updated to filesystem version 3 by Daniel Aragones
*/
#include "minix.h"
#include <linux/buffer_head.h>
#include <linux/highmem.h>
#include <linux/swap.h>
typedef struct minix_dir_entry minix_dirent;
typedef struct minix3_dir_entry minix3_dirent;
static int minix_readdir(struct file *, struct dir_context *);
const struct file_operations minix_dir_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
.iterate_shared = minix_readdir,
.fsync = generic_file_fsync,
};
static inline void dir_put_page(struct page *page)
{
kunmap(page);
put_page(page);
}
/*
* Return the offset into page `page_nr' of the last valid
* byte in that page, plus one.
*/
static unsigned
minix_last_byte(struct inode *inode, unsigned long page_nr)
{
unsigned last_byte = PAGE_SIZE;
if (page_nr == (inode->i_size >> PAGE_SHIFT))
last_byte = inode->i_size & (PAGE_SIZE - 1);
return last_byte;
}
static int dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
{
struct address_space *mapping = page->mapping;
struct inode *dir = mapping->host;
int err = 0;
block_write_end(NULL, mapping, pos, len, len, page, NULL);
if (pos+len > dir->i_size) {
i_size_write(dir, pos+len);
mark_inode_dirty(dir);
}
if (IS_DIRSYNC(dir))
err = write_one_page(page);
else
unlock_page(page);
return err;
}
static struct page * dir_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);
return page;
}
static inline void *minix_next_entry(void *de, struct minix_sb_info *sbi)
{
return (void*)((char*)de + sbi->s_dirsize);
}
static int minix_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
struct minix_sb_info *sbi = minix_sb(sb);
unsigned chunk_size = sbi->s_dirsize;
unsigned long npages = dir_pages(inode);
unsigned long pos = ctx->pos;
unsigned offset;
unsigned long n;
ctx->pos = pos = ALIGN(pos, chunk_size);
if (pos >= inode->i_size)
return 0;
offset = pos & ~PAGE_MASK;
n = pos >> PAGE_SHIFT;
for ( ; n < npages; n++, offset = 0) {
char *p, *kaddr, *limit;
struct page *page = dir_get_page(inode, n);
if (IS_ERR(page))
continue;
kaddr = (char *)page_address(page);
p = kaddr+offset;
limit = kaddr + minix_last_byte(inode, n) - chunk_size;
for ( ; p <= limit; p = minix_next_entry(p, sbi)) {
const char *name;
__u32 inumber;
if (sbi->s_version == MINIX_V3) {
minix3_dirent *de3 = (minix3_dirent *)p;
name = de3->name;
inumber = de3->inode;
} else {
minix_dirent *de = (minix_dirent *)p;
name = de->name;
inumber = de->inode;
}
if (inumber) {
unsigned l = strnlen(name, sbi->s_namelen);
if (!dir_emit(ctx, name, l,
inumber, DT_UNKNOWN)) {
dir_put_page(page);
return 0;
}
}
ctx->pos += chunk_size;
}
dir_put_page(page);
}
return 0;
}
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);
}
/*
* minix_find_entry()
*
* finds an entry in the specified directory with the wanted name. It
* returns the cache buffer in which the entry was found, and the entry
* itself (as a parameter - res_dir). It does NOT read the inode of the
* entry - you'll have to do that yourself if you want to.
*/
minix_dirent *minix_find_entry(struct dentry *dentry, struct page **res_page)
{
const char * name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct inode * dir = d_inode(dentry->d_parent);
struct super_block * sb = dir->i_sb;
struct minix_sb_info * sbi = minix_sb(sb);
unsigned long n;
unsigned long npages = dir_pages(dir);
struct page *page = NULL;
char *p;
char *namx;
__u32 inumber;
*res_page = NULL;
for (n = 0; n < npages; n++) {
char *kaddr, *limit;
page = dir_get_page(dir, n);
if (IS_ERR(page))
continue;
kaddr = (char*)page_address(page);
limit = kaddr + minix_last_byte(dir, n) - sbi->s_dirsize;
for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
if (sbi->s_version == MINIX_V3) {
minix3_dirent *de3 = (minix3_dirent *)p;
namx = de3->name;
inumber = de3->inode;
} else {
minix_dirent *de = (minix_dirent *)p;
namx = de->name;
inumber = de->inode;
}
if (!inumber)
continue;
if (namecompare(namelen, sbi->s_namelen, name, namx))
goto found;
}
dir_put_page(page);
}
return NULL;
found:
*res_page = page;
return (minix_dirent *)p;
}
int minix_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 super_block * sb = dir->i_sb;
struct minix_sb_info * sbi = minix_sb(sb);
struct page *page = NULL;
unsigned long npages = dir_pages(dir);
unsigned long n;
char *kaddr, *p;
minix_dirent *de;
minix3_dirent *de3;
loff_t pos;
int err;
char *namx = NULL;
__u32 inumber;
/*
* We take care of directory expansion in the same loop
* This code plays outside i_size, so it locks the page
* to protect that region.
*/
for (n = 0; n <= npages; n++) {
char *limit, *dir_end;
page = dir_get_page(dir, n);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
lock_page(page);
kaddr = (char*)page_address(page);
dir_end = kaddr + minix_last_byte(dir, n);
limit = kaddr + PAGE_SIZE - sbi->s_dirsize;
for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
de = (minix_dirent *)p;
de3 = (minix3_dirent *)p;
if (sbi->s_version == MINIX_V3) {
namx = de3->name;
inumber = de3->inode;
} else {
namx = de->name;
inumber = de->inode;
}
if (p == dir_end) {
/* We hit i_size */
if (sbi->s_version == MINIX_V3)
de3->inode = 0;
else
de->inode = 0;
goto got_it;
}
if (!inumber)
goto got_it;
err = -EEXIST;
if (namecompare(namelen, sbi->s_namelen, name, namx))
goto out_unlock;
}
unlock_page(page);
dir_put_page(page);
}
BUG();
return -EINVAL;
got_it:
pos = page_offset(page) + p - (char *)page_address(page);
err = minix_prepare_chunk(page, pos, sbi->s_dirsize);
if (err)
goto out_unlock;
memcpy (namx, name, namelen);
if (sbi->s_version == MINIX_V3) {
memset (namx + namelen, 0, sbi->s_dirsize - namelen - 4);
de3->inode = inode->i_ino;
} else {
memset (namx + namelen, 0, sbi->s_dirsize - namelen - 2);
de->inode = inode->i_ino;
}
err = dir_commit_chunk(page, pos, sbi->s_dirsize);
dir->i_mtime = dir->i_ctime = current_time(dir);
mark_inode_dirty(dir);
out_put:
dir_put_page(page);
out:
return err;
out_unlock:
unlock_page(page);
goto out_put;
}
int minix_delete_entry(struct minix_dir_entry *de, struct page *page)
{
struct inode *inode = page->mapping->host;
char *kaddr = page_address(page);
loff_t pos = page_offset(page) + (char*)de - kaddr;
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
unsigned len = sbi->s_dirsize;
int err;
lock_page(page);
err = minix_prepare_chunk(page, pos, len);
if (err == 0) {
if (sbi->s_version == MINIX_V3)
((minix3_dirent *) de)->inode = 0;
else
de->inode = 0;
err = dir_commit_chunk(page, pos, len);
} else {
unlock_page(page);
}
dir_put_page(page);
inode->i_ctime = inode->i_mtime = current_time(inode);
mark_inode_dirty(inode);
return err;
}
int minix_make_empty(struct inode *inode, struct inode *dir)
{
struct page *page = grab_cache_page(inode->i_mapping, 0);
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
char *kaddr;
int err;
if (!page)
return -ENOMEM;
err = minix_prepare_chunk(page, 0, 2 * sbi->s_dirsize);
if (err) {
unlock_page(page);
goto fail;
}
kaddr = kmap_atomic(page);
memset(kaddr, 0, PAGE_SIZE);
if (sbi->s_version == MINIX_V3) {
minix3_dirent *de3 = (minix3_dirent *)kaddr;
de3->inode = inode->i_ino;
strcpy(de3->name, ".");
de3 = minix_next_entry(de3, sbi);
de3->inode = dir->i_ino;
strcpy(de3->name, "..");
} else {
minix_dirent *de = (minix_dirent *)kaddr;
de->inode = inode->i_ino;
strcpy(de->name, ".");
de = minix_next_entry(de, sbi);
de->inode = dir->i_ino;
strcpy(de->name, "..");
}
kunmap_atomic(kaddr);
err = dir_commit_chunk(page, 0, 2 * sbi->s_dirsize);
fail:
put_page(page);
return err;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*/
int minix_empty_dir(struct inode * inode)
{
struct page *page = NULL;
unsigned long i, npages = dir_pages(inode);
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
char *name;
__u32 inumber;
for (i = 0; i < npages; i++) {
char *p, *kaddr, *limit;
page = dir_get_page(inode, i);
if (IS_ERR(page))
continue;
kaddr = (char *)page_address(page);
limit = kaddr + minix_last_byte(inode, i) - sbi->s_dirsize;
for (p = kaddr; p <= limit; p = minix_next_entry(p, sbi)) {
if (sbi->s_version == MINIX_V3) {
minix3_dirent *de3 = (minix3_dirent *)p;
name = de3->name;
inumber = de3->inode;
} else {
minix_dirent *de = (minix_dirent *)p;
name = de->name;
inumber = de->inode;
}
if (inumber != 0) {
/* check for . and .. */
if (name[0] != '.')
goto not_empty;
if (!name[1]) {
if (inumber != inode->i_ino)
goto not_empty;
} else if (name[1] != '.')
goto not_empty;
else if (name[2])
goto not_empty;
}
}
dir_put_page(page);
}
return 1;
not_empty:
dir_put_page(page);
return 0;
}
/* Releases the page */
void minix_set_link(struct minix_dir_entry *de, struct page *page,
struct inode *inode)
{
struct inode *dir = page->mapping->host;
struct minix_sb_info *sbi = minix_sb(dir->i_sb);
loff_t pos = page_offset(page) +
(char *)de-(char*)page_address(page);
int err;
lock_page(page);
err = minix_prepare_chunk(page, pos, sbi->s_dirsize);
if (err == 0) {
if (sbi->s_version == MINIX_V3)
((minix3_dirent *) de)->inode = inode->i_ino;
else
de->inode = inode->i_ino;
err = dir_commit_chunk(page, pos, sbi->s_dirsize);
} else {
unlock_page(page);
}
dir_put_page(page);
dir->i_mtime = dir->i_ctime = current_time(dir);
mark_inode_dirty(dir);
}
struct minix_dir_entry * minix_dotdot (struct inode *dir, struct page **p)
{
struct page *page = dir_get_page(dir, 0);
struct minix_sb_info *sbi = minix_sb(dir->i_sb);
struct minix_dir_entry *de = NULL;
if (!IS_ERR(page)) {
de = minix_next_entry(page_address(page), sbi);
*p = page;
}
return de;
}
ino_t minix_inode_by_name(struct dentry *dentry)
{
struct page *page;
struct minix_dir_entry *de = minix_find_entry(dentry, &page);
ino_t res = 0;
if (de) {
struct address_space *mapping = page->mapping;
struct inode *inode = mapping->host;
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
if (sbi->s_version == MINIX_V3)
res = ((minix3_dirent *) de)->inode;
else
res = de->inode;
dir_put_page(page);
}
return res;
}