WSL2-Linux-Kernel/fs/isofs/dir.c

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/*
* linux/fs/isofs/dir.c
*
* (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO 9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*
* Steve Beynon : Missing last directory entries fixed
* (stephen@askone.demon.co.uk) : 21st June 1996
*
* isofs directory handling functions
*/
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 11:04:11 +03:00
#include <linux/gfp.h>
#include "isofs.h"
int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode)
{
char * old = de->name;
int len = de->name_len[0];
int i;
for (i = 0; i < len; i++) {
unsigned char c = old[i];
if (!c)
break;
if (c >= 'A' && c <= 'Z')
c |= 0x20; /* lower case */
/* Drop trailing '.;1' (ISO 9660:1988 7.5.1 requires period) */
if (c == '.' && i == len - 3 && old[i + 1] == ';' && old[i + 2] == '1')
break;
/* Drop trailing ';1' */
if (c == ';' && i == len - 2 && old[i + 1] == '1')
break;
/* Convert remaining ';' to '.' */
/* Also '/' to '.' (broken Acorn-generated ISO9660 images) */
if (c == ';' || c == '/')
c = '.';
new[i] = c;
}
return i;
}
/* Acorn extensions written by Matthew Wilcox <willy@bofh.ai> 1998 */
int get_acorn_filename(struct iso_directory_record *de,
char *retname, struct inode *inode)
{
int std;
unsigned char *chr;
int retnamlen = isofs_name_translate(de, retname, inode);
if (retnamlen == 0)
return 0;
std = sizeof(struct iso_directory_record) + de->name_len[0];
if (std & 1)
std++;
if ((*((unsigned char *) de) - std) != 32)
return retnamlen;
chr = ((unsigned char *) de) + std;
if (strncmp(chr, "ARCHIMEDES", 10))
return retnamlen;
if ((*retname == '_') && ((chr[19] & 1) == 1))
*retname = '!';
if (((de->flags[0] & 2) == 0) && (chr[13] == 0xff)
&& ((chr[12] & 0xf0) == 0xf0)) {
retname[retnamlen] = ',';
sprintf(retname+retnamlen+1, "%3.3x",
((chr[12] & 0xf) << 8) | chr[11]);
retnamlen += 4;
}
return retnamlen;
}
/*
* This should _really_ be cleaned up some day..
*/
static int do_isofs_readdir(struct inode *inode, struct file *file,
struct dir_context *ctx,
char *tmpname, struct iso_directory_record *tmpde)
{
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
unsigned char bufbits = ISOFS_BUFFER_BITS(inode);
unsigned long block, offset, block_saved, offset_saved;
unsigned long inode_number = 0; /* Quiet GCC */
struct buffer_head *bh = NULL;
int len;
int map;
int first_de = 1;
char *p = NULL; /* Quiet GCC */
struct iso_directory_record *de;
struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb);
offset = ctx->pos & (bufsize - 1);
block = ctx->pos >> bufbits;
while (ctx->pos < inode->i_size) {
int de_len;
if (!bh) {
bh = isofs_bread(inode, block);
if (!bh)
return 0;
}
de = (struct iso_directory_record *) (bh->b_data + offset);
de_len = *(unsigned char *)de;
/*
* If the length byte is zero, we should move on to the next
* CDROM sector. If we are at the end of the directory, we
* kick out of the while loop.
*/
if (de_len == 0) {
brelse(bh);
bh = NULL;
ctx->pos = (ctx->pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1);
block = ctx->pos >> bufbits;
offset = 0;
continue;
}
block_saved = block;
offset_saved = offset;
offset += de_len;
/* Make sure we have a full directory entry */
if (offset >= bufsize) {
int slop = bufsize - offset + de_len;
memcpy(tmpde, de, slop);
offset &= bufsize - 1;
block++;
brelse(bh);
bh = NULL;
if (offset) {
bh = isofs_bread(inode, block);
if (!bh)
return 0;
memcpy((void *) tmpde + slop, bh->b_data, offset);
}
de = tmpde;
}
/* Basic sanity check, whether name doesn't exceed dir entry */
if (de_len < de->name_len[0] +
sizeof(struct iso_directory_record)) {
printk(KERN_NOTICE "iso9660: Corrupted directory entry"
" in block %lu of inode %lu\n", block,
inode->i_ino);
return -EIO;
}
if (first_de) {
isofs_normalize_block_and_offset(de,
&block_saved,
&offset_saved);
inode_number = isofs_get_ino(block_saved,
offset_saved, bufbits);
}
if (de->flags[-sbi->s_high_sierra] & 0x80) {
first_de = 0;
ctx->pos += de_len;
continue;
}
first_de = 1;
/* Handle the case of the '.' directory */
if (de->name_len[0] == 1 && de->name[0] == 0) {
if (!dir_emit_dot(file, ctx))
break;
ctx->pos += de_len;
continue;
}
len = 0;
/* Handle the case of the '..' directory */
if (de->name_len[0] == 1 && de->name[0] == 1) {
if (!dir_emit_dotdot(file, ctx))
break;
ctx->pos += de_len;
continue;
}
/* Handle everything else. Do name translation if there
is no Rock Ridge NM field. */
/*
* Do not report hidden files if so instructed, or associated
* files unless instructed to do so
*/
if ((sbi->s_hide && (de->flags[-sbi->s_high_sierra] & 1)) ||
(!sbi->s_showassoc &&
(de->flags[-sbi->s_high_sierra] & 4))) {
ctx->pos += de_len;
continue;
}
map = 1;
if (sbi->s_rock) {
len = get_rock_ridge_filename(de, tmpname, inode);
if (len != 0) { /* may be -1 */
p = tmpname;
map = 0;
}
}
if (map) {
#ifdef CONFIG_JOLIET
if (sbi->s_joliet_level) {
len = get_joliet_filename(de, tmpname, inode);
p = tmpname;
} else
#endif
if (sbi->s_mapping == 'a') {
len = get_acorn_filename(de, tmpname, inode);
p = tmpname;
} else
if (sbi->s_mapping == 'n') {
len = isofs_name_translate(de, tmpname, inode);
p = tmpname;
} else {
p = de->name;
len = de->name_len[0];
}
}
if (len > 0) {
if (!dir_emit(ctx, p, len, inode_number, DT_UNKNOWN))
break;
}
ctx->pos += de_len;
continue;
}
if (bh)
brelse(bh);
return 0;
}
/*
* Handle allocation of temporary space for name translation and
* handling split directory entries.. The real work is done by
* "do_isofs_readdir()".
*/
static int isofs_readdir(struct file *file, struct dir_context *ctx)
{
int result;
char *tmpname;
struct iso_directory_record *tmpde;
struct inode *inode = file_inode(file);
tmpname = (char *)__get_free_page(GFP_KERNEL);
if (tmpname == NULL)
return -ENOMEM;
tmpde = (struct iso_directory_record *) (tmpname+1024);
result = do_isofs_readdir(inode, file, ctx, tmpname, tmpde);
free_page((unsigned long) tmpname);
return result;
}
const struct file_operations isofs_dir_operations =
{
.llseek = generic_file_llseek,
.read = generic_read_dir,
.iterate = isofs_readdir,
};
/*
* directories can handle most operations...
*/
const struct inode_operations isofs_dir_inode_operations =
{
.lookup = isofs_lookup,
};