1 #include "fs.h"
2 #include <string.h>
3 #include <sys/stat.h>
4 #include <sys/statvfs.h>
5 #include "inode.h"
6 #include "super.h"
7
8 /*===========================================================================*
9 * estimate_blocks *
10 *===========================================================================*/
estimate_blocks(struct inode * rip)11 static blkcnt_t estimate_blocks(struct inode *rip)
12 {
13 /* Return the number of 512-byte blocks used by this file. This includes space
14 * used by data zones and indirect blocks (actually also zones). Reading in all
15 * indirect blocks is too costly for a stat call, so we disregard holes and
16 * return a conservative estimation.
17 */
18 blkcnt_t zones, sindirs, dindirs, nr_indirs, sq_indirs;
19 unsigned int zone_size;
20
21 /* Compute the number of zones used by the file. */
22 zone_size = rip->i_sp->s_block_size << rip->i_sp->s_log_zone_size;
23
24 zones = (blkcnt_t) ((rip->i_size + zone_size - 1) / zone_size);
25
26 /* Compute the number of indirect blocks needed for that zone count. */
27 nr_indirs = (blkcnt_t) rip->i_nindirs;
28 sq_indirs = nr_indirs * nr_indirs;
29
30 sindirs = (zones - (blkcnt_t) rip->i_ndzones + nr_indirs - 1) / nr_indirs;
31 dindirs = (sindirs - 1 + sq_indirs - 1) / sq_indirs;
32
33 /* Return the number of 512-byte blocks corresponding to the number of data
34 * zones and indirect blocks.
35 */
36 return (zones + sindirs + dindirs) * (blkcnt_t) (zone_size / 512);
37 }
38
39
40 /*===========================================================================*
41 * fs_stat *
42 *===========================================================================*/
fs_stat(ino_t ino_nr,struct stat * statbuf)43 int fs_stat(ino_t ino_nr, struct stat *statbuf)
44 {
45 struct inode *rip;
46 mode_t mo;
47 int s;
48
49 if ((rip = get_inode(fs_dev, ino_nr)) == NULL)
50 return(EINVAL);
51
52 /* Update the atime, ctime, and mtime fields in the inode, if need be. */
53 if (rip->i_update) update_times(rip);
54
55 /* Fill in the statbuf struct. */
56 mo = rip->i_mode & I_TYPE;
57
58 /* true iff special */
59 s = (mo == I_CHAR_SPECIAL || mo == I_BLOCK_SPECIAL);
60
61 statbuf->st_mode = (mode_t) rip->i_mode;
62 statbuf->st_nlink = (nlink_t) rip->i_nlinks;
63 statbuf->st_uid = rip->i_uid;
64 statbuf->st_gid = rip->i_gid;
65 statbuf->st_rdev = (s ? (dev_t)rip->i_zone[0] : NO_DEV);
66 statbuf->st_size = rip->i_size;
67 statbuf->st_atime = rip->i_atime;
68 statbuf->st_mtime = rip->i_mtime;
69 statbuf->st_ctime = rip->i_ctime;
70 statbuf->st_blksize = lmfs_fs_block_size();
71 statbuf->st_blocks = estimate_blocks(rip);
72
73 put_inode(rip); /* release the inode */
74
75 return(OK);
76 }
77
78
79 /*===========================================================================*
80 * fs_statvfs *
81 *===========================================================================*/
fs_statvfs(struct statvfs * st)82 int fs_statvfs(struct statvfs *st)
83 {
84 struct super_block *sp;
85 int scale;
86
87 sp = &superblock;
88
89 scale = sp->s_log_zone_size;
90
91 st->f_blocks = sp->s_zones;
92 st->f_bfree = sp->s_zones - used_zones;
93 st->f_bavail = st->f_bfree;
94
95 st->f_bsize = sp->s_block_size << scale;
96 st->f_frsize = sp->s_block_size;
97 st->f_iosize = st->f_frsize;
98 st->f_files = sp->s_ninodes;
99 st->f_ffree = count_free_bits(sp, IMAP);
100 st->f_favail = st->f_ffree;
101 st->f_namemax = MFS_DIRSIZ;
102
103 return(OK);
104 }
105