~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/9p/vfs_dir.c

Version: ~ [ linux-5.8 ] ~ [ linux-5.7.14 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.57 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.138 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.193 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.232 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.232 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * linux/fs/9p/vfs_dir.c
  3  *
  4  * This file contains vfs directory ops for the 9P2000 protocol.
  5  *
  6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
  7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
  8  *
  9  *  This program is free software; you can redistribute it and/or modify
 10  *  it under the terms of the GNU General Public License version 2
 11  *  as published by the Free Software Foundation.
 12  *
 13  *  This program is distributed in the hope that it will be useful,
 14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16  *  GNU General Public License for more details.
 17  *
 18  *  You should have received a copy of the GNU General Public License
 19  *  along with this program; if not, write to:
 20  *  Free Software Foundation
 21  *  51 Franklin Street, Fifth Floor
 22  *  Boston, MA  02111-1301  USA
 23  *
 24  */
 25 
 26 #include <linux/module.h>
 27 #include <linux/errno.h>
 28 #include <linux/fs.h>
 29 #include <linux/file.h>
 30 #include <linux/stat.h>
 31 #include <linux/string.h>
 32 #include <linux/sched.h>
 33 #include <linux/inet.h>
 34 #include <linux/idr.h>
 35 #include <linux/slab.h>
 36 #include <linux/uio.h>
 37 #include <net/9p/9p.h>
 38 #include <net/9p/client.h>
 39 
 40 #include "v9fs.h"
 41 #include "v9fs_vfs.h"
 42 #include "fid.h"
 43 
 44 /**
 45  * struct p9_rdir - readdir accounting
 46  * @head: start offset of current dirread buffer
 47  * @tail: end offset of current dirread buffer
 48  * @buf: dirread buffer
 49  *
 50  * private structure for keeping track of readdir
 51  * allocated on demand
 52  */
 53 
 54 struct p9_rdir {
 55         int head;
 56         int tail;
 57         uint8_t buf[];
 58 };
 59 
 60 /**
 61  * dt_type - return file type
 62  * @mistat: mistat structure
 63  *
 64  */
 65 
 66 static inline int dt_type(struct p9_wstat *mistat)
 67 {
 68         unsigned long perm = mistat->mode;
 69         int rettype = DT_REG;
 70 
 71         if (perm & P9_DMDIR)
 72                 rettype = DT_DIR;
 73         if (perm & P9_DMSYMLINK)
 74                 rettype = DT_LNK;
 75 
 76         return rettype;
 77 }
 78 
 79 /**
 80  * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
 81  * @filp: opened file structure
 82  * @buflen: Length in bytes of buffer to allocate
 83  *
 84  */
 85 
 86 static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
 87 {
 88         struct p9_fid *fid = filp->private_data;
 89         if (!fid->rdir)
 90                 fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
 91         return fid->rdir;
 92 }
 93 
 94 /**
 95  * v9fs_dir_readdir - iterate through a directory
 96  * @file: opened file structure
 97  * @ctx: actor we feed the entries to
 98  *
 99  */
100 
101 static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
102 {
103         bool over;
104         struct p9_wstat st;
105         int err = 0;
106         struct p9_fid *fid;
107         int buflen;
108         struct p9_rdir *rdir;
109         struct kvec kvec;
110 
111         p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
112         fid = file->private_data;
113 
114         buflen = fid->clnt->msize - P9_IOHDRSZ;
115 
116         rdir = v9fs_alloc_rdir_buf(file, buflen);
117         if (!rdir)
118                 return -ENOMEM;
119         kvec.iov_base = rdir->buf;
120         kvec.iov_len = buflen;
121 
122         while (1) {
123                 if (rdir->tail == rdir->head) {
124                         struct iov_iter to;
125                         int n;
126                         iov_iter_kvec(&to, READ, &kvec, 1, buflen);
127                         n = p9_client_read(file->private_data, ctx->pos, &to,
128                                            &err);
129                         if (err)
130                                 return err;
131                         if (n == 0)
132                                 return 0;
133 
134                         rdir->head = 0;
135                         rdir->tail = n;
136                 }
137                 while (rdir->head < rdir->tail) {
138                         err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
139                                           rdir->tail - rdir->head, &st);
140                         if (err <= 0) {
141                                 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
142                                 return -EIO;
143                         }
144 
145                         over = !dir_emit(ctx, st.name, strlen(st.name),
146                                          v9fs_qid2ino(&st.qid), dt_type(&st));
147                         p9stat_free(&st);
148                         if (over)
149                                 return 0;
150 
151                         rdir->head += err;
152                         ctx->pos += err;
153                 }
154         }
155 }
156 
157 /**
158  * v9fs_dir_readdir_dotl - iterate through a directory
159  * @file: opened file structure
160  * @ctx: actor we feed the entries to
161  *
162  */
163 static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
164 {
165         int err = 0;
166         struct p9_fid *fid;
167         int buflen;
168         struct p9_rdir *rdir;
169         struct p9_dirent curdirent;
170 
171         p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
172         fid = file->private_data;
173 
174         buflen = fid->clnt->msize - P9_READDIRHDRSZ;
175 
176         rdir = v9fs_alloc_rdir_buf(file, buflen);
177         if (!rdir)
178                 return -ENOMEM;
179 
180         while (1) {
181                 if (rdir->tail == rdir->head) {
182                         err = p9_client_readdir(fid, rdir->buf, buflen,
183                                                 ctx->pos);
184                         if (err <= 0)
185                                 return err;
186 
187                         rdir->head = 0;
188                         rdir->tail = err;
189                 }
190 
191                 while (rdir->head < rdir->tail) {
192 
193                         err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
194                                             rdir->tail - rdir->head,
195                                             &curdirent);
196                         if (err < 0) {
197                                 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
198                                 return -EIO;
199                         }
200 
201                         if (!dir_emit(ctx, curdirent.d_name,
202                                       strlen(curdirent.d_name),
203                                       v9fs_qid2ino(&curdirent.qid),
204                                       curdirent.d_type))
205                                 return 0;
206 
207                         ctx->pos = curdirent.d_off;
208                         rdir->head += err;
209                 }
210         }
211 }
212 
213 
214 /**
215  * v9fs_dir_release - close a directory
216  * @inode: inode of the directory
217  * @filp: file pointer to a directory
218  *
219  */
220 
221 int v9fs_dir_release(struct inode *inode, struct file *filp)
222 {
223         struct p9_fid *fid;
224 
225         fid = filp->private_data;
226         p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
227                  inode, filp, fid ? fid->fid : -1);
228         if (fid)
229                 p9_client_clunk(fid);
230         return 0;
231 }
232 
233 const struct file_operations v9fs_dir_operations = {
234         .read = generic_read_dir,
235         .llseek = generic_file_llseek,
236         .iterate_shared = v9fs_dir_readdir,
237         .open = v9fs_file_open,
238         .release = v9fs_dir_release,
239 };
240 
241 const struct file_operations v9fs_dir_operations_dotl = {
242         .read = generic_read_dir,
243         .llseek = generic_file_llseek,
244         .iterate_shared = v9fs_dir_readdir_dotl,
245         .open = v9fs_file_open,
246         .release = v9fs_dir_release,
247         .fsync = v9fs_file_fsync_dotl,
248 };
249 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp