1/* SPDX-License-Identifier: GPL-2.0 */
  2#include <linux/fs.h>
  3#include <linux/qnx4_fs.h>
  4
  5#define QNX4_DEBUG 0
  6
  7#if QNX4_DEBUG
  8#define QNX4DEBUG(X) printk X
  9#else
 10#define QNX4DEBUG(X) (void) 0
 11#endif
 12
 13struct qnx4_sb_info {
 14	unsigned int		Version;	/* may be useful */
 15	struct qnx4_inode_entry	*BitMap;	/* useful */
 16};
 17
 18struct qnx4_inode_info {
 19	struct qnx4_inode_entry raw;
 20	loff_t mmu_private;
 21	struct inode vfs_inode;
 22};
 23
 24extern struct inode *qnx4_iget(struct super_block *, unsigned long);
 25extern struct dentry *qnx4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags);
 26extern unsigned long qnx4_count_free_blocks(struct super_block *sb);
 27extern unsigned long qnx4_block_map(struct inode *inode, long iblock);
 28
 29extern const struct inode_operations qnx4_dir_inode_operations;
 30extern const struct file_operations qnx4_dir_operations;
 31extern int qnx4_is_free(struct super_block *sb, long block);
 32
 33static inline struct qnx4_sb_info *qnx4_sb(struct super_block *sb)
 34{
 35	return sb->s_fs_info;
 36}
 37
 38static inline struct qnx4_inode_info *qnx4_i(struct inode *inode)
 39{
 40	return container_of(inode, struct qnx4_inode_info, vfs_inode);
 41}
 42
 43static inline struct qnx4_inode_entry *qnx4_raw_inode(struct inode *inode)
 44{
 45	return &qnx4_i(inode)->raw;
 46}
 47
 48/*
 49 * A qnx4 directory entry is an inode entry or link info
 50 * depending on the status field in the last byte. The
 51 * first byte is where the name start either way, and a
 52 * zero means it's empty.
 53 *
 54 * Also, due to a bug in gcc, we don't want to use the
 55 * real (differently sized) name arrays in the inode and
 56 * link entries, but always the 'de_name[]' one in the
 57 * fake struct entry.
 58 *
 59 * See
 60 *
 61 *   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578#c6
 62 *
 63 * for details, but basically gcc will take the size of the
 64 * 'name' array from one of the used union entries randomly.
 65 *
 66 * This use of 'de_name[]' (48 bytes) avoids the false positive
 67 * warnings that would happen if gcc decides to use 'inode.di_name'
 68 * (16 bytes) even when the pointer and size were to come from
 69 * 'link.dl_name' (48 bytes).
 70 *
 71 * In all cases the actual name pointer itself is the same, it's
 72 * only the gcc internal 'what is the size of this field' logic
 73 * that can get confused.
 74 */
 75union qnx4_directory_entry {
 76	struct {
 77		const char de_name[48];
 78		u8 de_pad[15];
 79		u8 de_status;
 80	};
 81	struct qnx4_inode_entry inode;
 82	struct qnx4_link_info link;
 83};
 84
 85static inline const char *get_entry_fname(union qnx4_directory_entry *de,
 86					  int *size)
 87{
 88	/* Make sure the status byte is in the same place for all structs. */
 89	BUILD_BUG_ON(offsetof(struct qnx4_inode_entry, di_status) !=
 90			offsetof(struct qnx4_link_info, dl_status));
 91	BUILD_BUG_ON(offsetof(struct qnx4_inode_entry, di_status) !=
 92			offsetof(union qnx4_directory_entry, de_status));
 93
 94	if (!de->de_name[0])
 95		return NULL;
 96	if (!(de->de_status & (QNX4_FILE_USED|QNX4_FILE_LINK)))
 97		return NULL;
 98	if (!(de->de_status & QNX4_FILE_LINK))
 99		*size = sizeof(de->inode.di_fname);
100	else
101		*size = sizeof(de->link.dl_fname);
102
103	*size = strnlen(de->de_name, *size);
104
105	return de->de_name;
106}

 
 1#include <linux/fs.h>
 2#include <linux/qnx4_fs.h>
 3
 4#define QNX4_DEBUG 0
 5
 6#if QNX4_DEBUG
 7#define QNX4DEBUG(X) printk X
 8#else
 9#define QNX4DEBUG(X) (void) 0
10#endif
11
12struct qnx4_sb_info {
13	unsigned int		Version;	/* may be useful */
14	struct qnx4_inode_entry	*BitMap;	/* useful */
15};
16
17struct qnx4_inode_info {
18	struct qnx4_inode_entry raw;
19	loff_t mmu_private;
20	struct inode vfs_inode;
21};
22
23extern struct inode *qnx4_iget(struct super_block *, unsigned long);
24extern struct dentry *qnx4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags);
25extern unsigned long qnx4_count_free_blocks(struct super_block *sb);
26extern unsigned long qnx4_block_map(struct inode *inode, long iblock);
27
28extern const struct inode_operations qnx4_dir_inode_operations;
29extern const struct file_operations qnx4_dir_operations;
30extern int qnx4_is_free(struct super_block *sb, long block);
31
32static inline struct qnx4_sb_info *qnx4_sb(struct super_block *sb)
33{
34	return sb->s_fs_info;
35}
36
37static inline struct qnx4_inode_info *qnx4_i(struct inode *inode)
38{
39	return container_of(inode, struct qnx4_inode_info, vfs_inode);
40}
41
42static inline struct qnx4_inode_entry *qnx4_raw_inode(struct inode *inode)
43{
44	return &qnx4_i(inode)->raw;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
45}