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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | pj | 1 | |
| 2 | #include <fs/types.h> |
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| 3 | #include <fs/errno.h> |
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| 4 | #include <fs/task.h> |
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| 5 | #include <fs/maccess.h> |
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| 6 | #include <fs/fcntl.h> |
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| 7 | |||
| 8 | #include "file.h" |
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| 9 | #include "inode.h" |
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| 10 | #include "dentry.h" |
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| 11 | #include "fileop.h" |
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| 12 | #include "rwlock.h" |
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| 13 | #include "fs.h" |
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| 14 | |||
| 15 | #define EBOH EIO |
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| 16 | |||
| 17 | /* temporary: for console i/o */ |
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| 18 | #include <ll/i386/cons.h> |
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| 19 | static int __getch(int flag) |
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| 20 | { |
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| 684 | giacomo | 21 | |
| 22 | return 0; |
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| 23 | |||
| 2 | pj | 24 | } |
| 25 | |||
| 26 | __ssize_t k_read(int fd, __ptr_t buf, __ssize_t nbytes) |
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| 27 | { |
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| 28 | __pid_t pid; |
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| 29 | __ssize_t sz; |
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| 30 | |||
| 31 | call_to_fs(); |
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| 32 | |||
| 33 | /* TO FIX! */ |
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| 34 | if (fd>=0&&fd<=2) { |
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| 35 | __ssize_t x; |
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| 36 | int ret,ch; |
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| 37 | char *c; |
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| 38 | |||
| 39 | //printk(KERN_INFO "reading from console"); |
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| 40 | |||
| 41 | /* WARNIG buf is a pointer into user-space |
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| 42 | * we are using it without cast |
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| 43 | */ |
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| 44 | |||
| 45 | /* WARNIG there is a blocking call... |
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| 46 | * the system can go down if it is blocked! |
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| 47 | */ |
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| 48 | |||
| 49 | if (fd!=0) return_from_fs(-EBADF); |
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| 50 | |||
| 51 | c=(char*)buf; |
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| 52 | x=0; |
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| 53 | while (x<nbytes) { |
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| 54 | ch=__getch(NON_BLOCK); |
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| 55 | if (ch!=-1) *c++=ch; |
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| 56 | else { |
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| 57 | if (x>0) break; |
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| 58 | release_sys_call(); |
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| 59 | ch=__getch(BLOCK); |
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| 60 | ret=reacquire_sys_call(); |
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| 61 | if (ret) return -ENOSYS; |
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| 62 | *c++=ch; |
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| 63 | } |
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| 64 | x++; |
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| 65 | cputc(ch); |
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| 66 | } |
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| 67 | |||
| 68 | return_from_fs(x); |
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| 69 | } |
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| 70 | |||
| 71 | /* don't try to use bad file descriptor */ |
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| 72 | pid=__get_pid(); |
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| 73 | if (check_fd(pid,fd)) { |
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| 74 | printk(KERN_INFO "k_read: using bad file descriptor"); |
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| 75 | return_from_fs(-EBADF); |
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| 76 | } |
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| 77 | |||
| 78 | /* don't try to read a directory */ |
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| 79 | if (file_ptr(pid,fd)->f_flag_isdir) return_from_fs(-EBADF); |
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| 80 | |||
| 81 | /* don't try to read into not user memory */ |
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| 82 | if (!__verify_write(buf,nbytes)) return_from_fs(-EVERIFY); |
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| 83 | |||
| 84 | /* if in write only mode */ |
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| 85 | if (*fildesfflags_ptr(pid,fd)&O_WRONLY) |
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| 86 | return_from_fs(-EBOH); |
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| 87 | |||
| 88 | /* cancellation point */ |
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| 89 | //fs_test_cancellation(-EINTR); |
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| 90 | |||
| 91 | /* acquire read lock on inode's file */ |
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| 92 | __rwlock_rdlock(&file_ptr(pid,fd)->f_dentry->d_inode->i_lock); |
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| 93 | |||
| 94 | /* O_APPEND flags */ |
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| 95 | if (*fildesfflags_ptr(pid,fd)&O_APPEND) { |
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| 96 | sz=0; |
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| 97 | goto SKIP; |
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| 98 | } |
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| 99 | |||
| 100 | /* WARNING buf is a pointer into user-space! */ |
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| 101 | sz=file_ptr(pid,fd)->f_op->read(file_ptr(pid,fd),buf,nbytes); |
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| 102 | |||
| 103 | /* release the lock */ |
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| 104 | SKIP: |
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| 105 | __rwlock_rdunlock(&file_ptr(pid,fd)->f_dentry->d_inode->i_lock); |
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| 106 | |||
| 107 | return_from_fs(sz); |
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| 108 | } |