/* * The I node is the focus of all * file activity in unix. There is a unique * inode allocated for each active file, * each current directory, each mounted-on * file, text file, and the root. An inode is 'named' * by its dev/inumber pair. (iget/iget.c) * Data, from mode on, is read in * from permanent inode on volume. */ #define NADDR 13 struct inode { short i_flag; u_char i_count; /* reference count */ char i_fstyp; /* type of its filesystem */ dev_t i_dev; /* device where inode resides */ long i_number; /* i number, 1-to-1 with device address */ unsigned short i_mode; short i_nlink; /* directory entries */ short i_uid; /* owner */ short i_gid; /* group of owner */ off_t i_size; /* size of file */ struct inode *i_mroot; /* if mount point, root inode */ struct inode *i_mpoint; /* inode of mount point */ struct stdata *i_sptr; /* stream associated with this inode */ union { struct { daddr_t I_addr[NADDR]; /* if normal file/directory */ daddr_t I_lastr; /* last read (for read-ahead) */ struct buf *I_bufp; /* buffer for super-block */ } i_f; #define i_addr i_f.I_addr #define i_lastr i_f.I_lastr #define i_bufp i_f.I_bufp struct { daddr_t I_rdev; /* i_addr[0] */ long I_key; /* see istread */ } i_d; #define i_rdev i_d.I_rdev #define i_key i_d.I_key struct { long I_tag; struct inode *I_cip; /* communications */ } i_a; /* when i_fstyp != 0 */ #define i_tag i_a.I_tag #define i_cip i_a.I_cip struct { struct proc *I_proc; /* sanity checking */ int I_sigmask; /* signal trace mask */ } i_p; #define i_proc i_p.I_proc #define i_sigmask i_p.I_sigmask } i_un; struct inode *i_hlink; /* link in hash chain (iget/iput/ifind) */ }; #ifdef KERNEL struct inode *inode, *inodeNINODE; int ninode; struct inode *rootdir; /* pointer to inode of root directory */ struct inode *ialloc(); struct inode *ifind(); struct inode *iget(); struct inode *owner(); struct inode *maknode(); struct inode *namei(); struct inode *openi(); #endif /* flags */ #define ILOCK 01 /* inode is locked */ #define IUPD 02 /* file has been modified */ #define IACC 04 /* inode access time to be updated */ #define IMOUNT 010 /* inode is mounted on */ #define IWANT 020 /* some process waiting on lock */ #define ITEXT 040 /* inode is pure text prototype */ #define ICHG 0100 /* inode has been changed */ #define IPIPE 0200 /* inode is a pipe */ #define IDEAD 0400 /* only iput and iget */ /* modes */ #define IFMT 0170000 /* type of file */ #define IFDIR 0040000 /* directory */ #define IFCHR 0020000 /* character special */ #define IFBLK 0060000 /* block special */ #define IFREG 0100000 /* regular */ #define IFLNK 0120000 /* symbolic link to another file */ #define ISUID 04000 /* set user id on execution */ #define ISGID 02000 /* set group id on execution */ #define IREAD 0400 /* read, write, execute permissions */ #define IWRITE 0200 #define IEXEC 0100 #define ICONC 0001000 /* this file is protected for concurrent access */ #define ICCTYP 0007000 /* type of concurrent access */ #define ISYNC 0001000 /* 1 writer and n readers (synchronized access) */ #define IEXCL 0003000 /* 1 writer or n readers (exclusive access) */ struct argnamei { /* namei's flag argument */ short flag; /* type of request */ short mode; /* mode for creating */ struct inode *il; /* for linking */ short done; /* used as a return flag in creat */ } nilargnamei; #define NI_DEL 1 /* unlink this file */ #define NI_CREAT 2 /* create it if it doesn't exits */ #define NI_NXCREAT 3 /* create it, error if it already exists */ #define NI_LINK 4 /* make a link */ #define NI_MKDIR 5 /* make a directory */ #define NI_RMDIR 6 /* remove a directory */ struct nx { /* arg to real nami */ struct inode *dp; char *cp; struct buf *nbp; int nlink; }; /* * some inline subroutines to speed things up */ #ifdef KERNEL #define plock(ip) \ { \ while ((ip)->i_flag & ILOCK) { \ (ip)->i_flag |= IWANT; \ sleep((caddr_t)(ip), PINOD); \ } \ (ip)->i_flag |= ILOCK; \ } #define prele(ip) \ { \ (ip)->i_flag &= ~ILOCK; \ if ((ip)->i_flag&IWANT) { \ (ip)->i_flag &= ~IWANT; \ wakeup((caddr_t)(ip)); \ } \ } #endif