minix/servers/ext2/type.h
Ben Gras bd3cde4571 Move primary cache code to libminixfs.
Add primary cache management feature to libminixfs as mfs and ext2
currently do separately, remove cache code from mfs and ext2, and make
them use the libminixfs interface. This makes all fields of the buf
struct private to libminixfs and FS clients aren't supposed to access
them at all. Only the opaque 'void *data' field (the FS block contents,
used to be called bp) is to be accessed by the FS client.

The main purpose is to implement the interface to the 2ndary vm cache
just once, get rid of some code duplication, and add a little
abstraction to reduce the code inertia of the whole caching business.

Some minor sanity checking and prohibition done by mfs in this code
as removed from the generic primary cache code as a result:
        - checking all inodes are not in use when allocating/resizing
          the cache
        - checking readonly filesystems aren't written to
        - checking the superblock isn't written to on mounted filesystems

The minixfslib code relies on fs_blockstats() in the client filesystem to
return some FS usage information.
2012-10-23 19:48:38 +02:00

101 lines
3.6 KiB
C

#ifndef EXT2_TYPE_H
#define EXT2_TYPE_H
#include <minix/libminixfs.h>
/* On the disk all attributes are stored in little endian format.
* Inode structure was taken from linux/include/linux/ext2_fs.h.
*/
typedef struct {
u16_t i_mode; /* File mode */
u16_t i_uid; /* Low 16 bits of Owner Uid */
u32_t i_size; /* Size in bytes */
u32_t i_atime; /* Access time */
u32_t i_ctime; /* Creation time */
u32_t i_mtime; /* Modification time */
u32_t i_dtime; /* Deletion Time */
u16_t i_gid; /* Low 16 bits of Group Id */
u16_t i_links_count; /* Links count */
u32_t i_blocks; /* Blocks count */
u32_t i_flags; /* File flags */
union {
struct {
u32_t l_i_reserved1;
} linux1;
struct {
u32_t h_i_translator;
} hurd1;
struct {
u32_t m_i_reserved1;
} masix1;
} osd1; /* OS dependent 1 */
u32_t i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
u32_t i_generation; /* File version (for NFS) */
u32_t i_file_acl; /* File ACL */
u32_t i_dir_acl; /* Directory ACL */
u32_t i_faddr; /* Fragment address */
union {
struct {
u8_t l_i_frag; /* Fragment number */
u8_t l_i_fsize; /* Fragment size */
u16_t i_pad1;
u16_t l_i_uid_high; /* these 2 fields */
u16_t l_i_gid_high; /* were reserved2[0] */
u32_t l_i_reserved2;
} linux2;
struct {
u8_t h_i_frag; /* Fragment number */
u8_t h_i_fsize; /* Fragment size */
u16_t h_i_mode_high;
u16_t h_i_uid_high;
u16_t h_i_gid_high;
u32_t h_i_author;
} hurd2;
struct {
u8_t m_i_frag; /* Fragment number */
u8_t m_i_fsize; /* Fragment size */
u16_t m_pad1;
u32_t m_i_reserved2[2];
} masix2;
} osd2; /* OS dependent 2 */
} d_inode;
/* Part of on disk directory (entry description).
* It includes all fields except name (since size is unknown.
* In revision 0 name_len is u16_t (here is structure of rev >= 0.5,
* where name_len was truncated with the upper 8 bit to add file_type).
* MIN_DIR_ENTRY_SIZE depends on this structure.
*/
struct ext2_disk_dir_desc {
u32_t d_ino;
u16_t d_rec_len;
u8_t d_name_len;
u8_t d_file_type;
char d_name[1];
};
/* Current position in block */
#define CUR_DISC_DIR_POS(cur_desc, base) ((char*)cur_desc - (char*)base)
/* Return pointer to the next dentry */
#define NEXT_DISC_DIR_DESC(cur_desc) ((struct ext2_disk_dir_desc*)\
((char*)cur_desc + cur_desc->d_rec_len))
/* Return next dentry's position in block */
#define NEXT_DISC_DIR_POS(cur_desc, base) (cur_desc->d_rec_len +\
CUR_DISC_DIR_POS(cur_desc, base))
/* Structure with options affecting global behavior. */
struct opt {
int use_orlov; /* Bool: Use Orlov allocator */
/* In ext2 there are reserved blocks, which can be used by super user only or
* user specified by resuid/resgid. Right now we can't check what user
* requested operation (VFS limitation), so it's a small warkaround.
*/
int mfsalloc; /* Bool: use mfslike allocator */
int use_reserved_blocks; /* Bool: small workaround */
unsigned int block_with_super;/* Int: where to read super block,
* uses 1k units. */
int use_prealloc; /* Bool: use preallocation */
};
#endif /* EXT2_TYPE_H */