linux/fs/isofs/rock.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/isofs/rock.c
 *
 *  (C) 1992, 1993  Eric Youngdale
 *
 *  Rock Ridge Extensions to iso9660
 */

#include <linux/slab.h>
#include <linux/pagemap.h>

#include "isofs.h"
#include "rock.h"

/*
 * These functions are designed to read the system areas of a directory record
 * and extract relevant information.  There are different functions provided
 * depending upon what information we need at the time.  One function fills
 * out an inode structure, a second one extracts a filename, a third one
 * returns a symbolic link name, and a fourth one returns the extent number
 * for the file.
 */

#define SIG(A,B) …

struct rock_state { … };

/*
 * This is a way of ensuring that we have something in the system
 * use fields that is compatible with Rock Ridge.  Return zero on success.
 */

static int check_sp(struct rock_ridge *rr, struct inode *inode)
{ … }

static void setup_rock_ridge(struct iso_directory_record *de,
			struct inode *inode, struct rock_state *rs)
{ … }

static void init_rock_state(struct rock_state *rs, struct inode *inode)
{ … }

/* Maximum number of Rock Ridge continuation entries */
#define RR_MAX_CE_ENTRIES …

/*
 * Returns 0 if the caller should continue scanning, 1 if the scan must end
 * and -ve on error.
 */
static int rock_continue(struct rock_state *rs)
{ … }

/*
 * We think there's a record of type `sig' at rs->chr.  Parse the signature
 * and make sure that there's really room for a record of that type.
 */
static int rock_check_overflow(struct rock_state *rs, int sig)
{ … }

/*
 * return length of name field; 0: not found, -1: to be ignored
 */
int get_rock_ridge_filename(struct iso_directory_record *de,
			    char *retname, struct inode *inode)
{ … }

#define RR_REGARD_XA …
#define RR_RELOC_DE …

static int
parse_rock_ridge_inode_internal(struct iso_directory_record *de,
				struct inode *inode, int flags)
{ … }

static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit)
{ … }

int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode,
			   int relocated)
{ … }

/*
 * read_folio() for symlinks: reads symlink contents into the folio and either
 * makes it uptodate and returns 0 or returns error (-EIO)
 */
static int rock_ridge_symlink_read_folio(struct file *file, struct folio *folio)
{ … }

const struct address_space_operations isofs_symlink_aops = …;