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-rw-r--r--fs/seq_file.c28
1 files changed, 15 insertions, 13 deletions
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 4023d6be939b..aa242dc99373 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -140,9 +140,21 @@ ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
140 140
141 mutex_lock(&m->lock); 141 mutex_lock(&m->lock);
142 142
143 /*
144 * seq_file->op->..m_start/m_stop/m_next may do special actions
145 * or optimisations based on the file->f_version, so we want to
146 * pass the file->f_version to those methods.
147 *
148 * seq_file->version is just copy of f_version, and seq_file
149 * methods can treat it simply as file version.
150 * It is copied in first and copied out after all operations.
151 * It is convenient to have it as part of structure to avoid the
152 * need of passing another argument to all the seq_file methods.
153 */
154 m->version = file->f_version;
155
143 /* Don't assume *ppos is where we left it */ 156 /* Don't assume *ppos is where we left it */
144 if (unlikely(*ppos != m->read_pos)) { 157 if (unlikely(*ppos != m->read_pos)) {
145 m->read_pos = *ppos;
146 while ((err = traverse(m, *ppos)) == -EAGAIN) 158 while ((err = traverse(m, *ppos)) == -EAGAIN)
147 ; 159 ;
148 if (err) { 160 if (err) {
@@ -152,21 +164,11 @@ ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
152 m->index = 0; 164 m->index = 0;
153 m->count = 0; 165 m->count = 0;
154 goto Done; 166 goto Done;
167 } else {
168 m->read_pos = *ppos;
155 } 169 }
156 } 170 }
157 171
158 /*
159 * seq_file->op->..m_start/m_stop/m_next may do special actions
160 * or optimisations based on the file->f_version, so we want to
161 * pass the file->f_version to those methods.
162 *
163 * seq_file->version is just copy of f_version, and seq_file
164 * methods can treat it simply as file version.
165 * It is copied in first and copied out after all operations.
166 * It is convenient to have it as part of structure to avoid the
167 * need of passing another argument to all the seq_file methods.
168 */
169 m->version = file->f_version;
170 /* grab buffer if we didn't have one */ 172 /* grab buffer if we didn't have one */
171 if (!m->buf) { 173 if (!m->buf) {
172 m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL); 174 m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);