Rev 3 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | pj | 1 | |
| 1063 | tullio | 2 | /* |
| 3 | * This program is free software; you can redistribute it and/or modify |
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| 4 | * it under the terms of the GNU General Public License as published by |
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| 5 | * the Free Software Foundation; either version 2 of the License, or |
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| 6 | * (at your option) any later version. |
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| 7 | * |
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| 8 | * This program is distributed in the hope that it will be useful, |
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| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 11 | * GNU General Public License for more details. |
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| 12 | * |
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| 13 | * You should have received a copy of the GNU General Public License |
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| 14 | * along with this program; if not, write to the Free Software |
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| 15 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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| 16 | * |
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| 17 | */ |
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| 18 | |||
| 2 | pj | 19 | #include <fs/types.h> |
| 20 | #include <fs/errno.h> |
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| 21 | #include <fs/task.h> |
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| 22 | #include <fs/maccess.h> |
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| 23 | #include <fs/fcntl.h> |
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| 24 | |||
| 25 | #include "file.h" |
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| 26 | #include "inode.h" |
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| 27 | #include "dentry.h" |
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| 28 | #include "fileop.h" |
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| 29 | #include "dentryop.h" |
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| 30 | #include "inodeop.h" |
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| 31 | #include "fsconst.h" |
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| 32 | #include "fs.h" |
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| 33 | |||
| 34 | int k_ftruncate(int fd, __off_t len) |
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| 35 | { |
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| 36 | struct inode *in; |
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| 37 | int res; |
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| 38 | __pid_t pid; |
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| 39 | |||
| 40 | call_to_fs(); |
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| 41 | |||
| 42 | /* don't try to use a bad file descriptor */ |
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| 43 | pid=__get_pid(); |
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| 44 | if (check_fd(pid,fd)) { |
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| 45 | printk(KERN_INFO "k_ftruncate: using bad file descriptor"); |
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| 46 | return_from_fs(-EBADF); |
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| 47 | } |
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| 48 | |||
| 49 | /* don't try to write a directory */ |
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| 50 | if (file_ptr(pid,fd)->f_flag_isdir) return_from_fs(-EBADF); |
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| 51 | |||
| 52 | /* if in read only mode (errno OK?)*/ |
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| 53 | if (*fildesfflags_ptr(pid,fd)&O_RDONLY) |
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| 54 | return_from_fs(-EPERM); |
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| 55 | |||
| 56 | /* acquire write lock on inode's file */ |
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| 57 | in=file_ptr(pid,fd)->f_dentry->d_inode; |
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| 58 | __rwlock_wrlock(&in->i_lock); |
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| 59 | |||
| 60 | /* |
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| 61 | if (*fildesfflags_ptr(pid,fd)&O_APPEND) |
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| 62 | if (file_ptr(pid,fd)->f_pos!= |
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| 63 | file_ptr(pid,fd)->f_dentry->d_inode->i_st.st_size) { |
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| 64 | __off_t off; |
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| 65 | off=file_ptr(pid,fd)->f_op->lseek(file_ptr(pid,fd),0,SEEK_END); |
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| 66 | if (off!=file_ptr(pid,fd)->f_dentry->d_inode->i_st.st_size) { |
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| 67 | sz=-ESPIPE; |
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| 68 | goto SKIP; |
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| 69 | } |
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| 70 | } |
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| 71 | */ |
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| 72 | |||
| 73 | /* truncate */ |
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| 74 | res=in->i_op->truncate(in,len); |
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| 75 | |||
| 76 | /* release the lock */ |
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| 77 | __rwlock_wrunlock(&in->i_lock); |
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| 78 | |||
| 79 | return_from_fs(res); |
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| 80 | } |