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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 "dentryop.h" |
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| 13 | #include "inodeop.h" |
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| 14 | #include "fsconst.h" |
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| 15 | #include "fs.h" |
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| 16 | |||
| 17 | int k_ftruncate(int fd, __off_t len) |
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| 18 | { |
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| 19 | struct inode *in; |
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| 20 | int res; |
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| 21 | __pid_t pid; |
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| 22 | |||
| 23 | call_to_fs(); |
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| 24 | |||
| 25 | /* don't try to use a bad file descriptor */ |
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| 26 | pid=__get_pid(); |
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| 27 | if (check_fd(pid,fd)) { |
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| 28 | printk(KERN_INFO "k_ftruncate: using bad file descriptor"); |
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| 29 | return_from_fs(-EBADF); |
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| 30 | } |
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| 31 | |||
| 32 | /* don't try to write a directory */ |
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| 33 | if (file_ptr(pid,fd)->f_flag_isdir) return_from_fs(-EBADF); |
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| 34 | |||
| 35 | /* if in read only mode (errno OK?)*/ |
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| 36 | if (*fildesfflags_ptr(pid,fd)&O_RDONLY) |
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| 37 | return_from_fs(-EPERM); |
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| 38 | |||
| 39 | /* acquire write lock on inode's file */ |
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| 40 | in=file_ptr(pid,fd)->f_dentry->d_inode; |
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| 41 | __rwlock_wrlock(&in->i_lock); |
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| 42 | |||
| 43 | /* |
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| 44 | if (*fildesfflags_ptr(pid,fd)&O_APPEND) |
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| 45 | if (file_ptr(pid,fd)->f_pos!= |
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| 46 | file_ptr(pid,fd)->f_dentry->d_inode->i_st.st_size) { |
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| 47 | __off_t off; |
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| 48 | off=file_ptr(pid,fd)->f_op->lseek(file_ptr(pid,fd),0,SEEK_END); |
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| 49 | if (off!=file_ptr(pid,fd)->f_dentry->d_inode->i_st.st_size) { |
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| 50 | sz=-ESPIPE; |
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| 51 | goto SKIP; |
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| 52 | } |
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| 53 | } |
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| 54 | */ |
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| 55 | |||
| 56 | /* truncate */ |
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| 57 | res=in->i_op->truncate(in,len); |
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| 58 | |||
| 59 | /* release the lock */ |
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| 60 | __rwlock_wrunlock(&in->i_lock); |
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| 61 | |||
| 62 | return_from_fs(res); |
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| 63 | } |