365 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			365 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * 9p backend
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|  *
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|  * Copyright IBM, Corp. 2011
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|  *
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|  * Authors:
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|  *  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2.  See
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|  * the COPYING file in the top-level directory.
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|  *
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include "fsdev/qemu-fsdev.h"
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| #include "qemu/thread.h"
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| #include "qemu/coroutine.h"
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| #include "coth.h"
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| 
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| static ssize_t __readlink(V9fsState *s, V9fsPath *path, V9fsString *buf)
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| {
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|     ssize_t len, maxlen = PATH_MAX;
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| 
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|     buf->data = g_malloc(PATH_MAX);
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|     for(;;) {
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|         len = s->ops->readlink(&s->ctx, path, buf->data, maxlen);
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|         if (len < 0) {
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|             g_free(buf->data);
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|             buf->data = NULL;
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|             buf->size = 0;
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|             break;
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|         } else if (len == maxlen) {
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|             /*
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|              * We dodn't have space to put the NULL or we have more
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|              * to read. Increase the size and try again
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|              */
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|             maxlen *= 2;
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|             g_free(buf->data);
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|             buf->data = g_malloc(maxlen);
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|             continue;
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|         }
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|         /*
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|          * Null terminate the readlink output
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|          */
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|         buf->data[len] = '\0';
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|         buf->size = len;
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|         break;
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|     }
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|     return len;
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| }
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| 
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| int v9fs_co_readlink(V9fsPDU *pdu, V9fsPath *path, V9fsString *buf)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = __readlink(s, path, buf);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_statfs(V9fsPDU *pdu, V9fsPath *path, struct statfs *stbuf)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->statfs(&s->ctx, path, stbuf);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_chmod(V9fsPDU *pdu, V9fsPath *path, mode_t mode)
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| {
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|     int err;
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|     FsCred cred;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     cred_init(&cred);
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|     cred.fc_mode = mode;
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->chmod(&s->ctx, path, &cred);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_utimensat(V9fsPDU *pdu, V9fsPath *path,
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|                       struct timespec times[2])
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->utimensat(&s->ctx, path, times);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_chown(V9fsPDU *pdu, V9fsPath *path, uid_t uid, gid_t gid)
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| {
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|     int err;
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|     FsCred cred;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     cred_init(&cred);
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|     cred.fc_uid = uid;
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|     cred.fc_gid = gid;
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->chown(&s->ctx, path, &cred);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_truncate(V9fsPDU *pdu, V9fsPath *path, off_t size)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->truncate(&s->ctx, path, size);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_mknod(V9fsPDU *pdu, V9fsFidState *fidp, V9fsString *name, uid_t uid,
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|                   gid_t gid, dev_t dev, mode_t mode, struct stat *stbuf)
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| {
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|     int err;
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|     V9fsPath path;
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|     FsCred cred;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     cred_init(&cred);
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|     cred.fc_uid  = uid;
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|     cred.fc_gid  = gid;
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|     cred.fc_mode = mode;
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|     cred.fc_rdev = dev;
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->mknod(&s->ctx, &fidp->path, name->data, &cred);
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|             if (err < 0) {
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|                 err = -errno;
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|             } else {
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|                 v9fs_path_init(&path);
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|                 err = v9fs_name_to_path(s, &fidp->path, name->data, &path);
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|                 if (!err) {
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|                     err = s->ops->lstat(&s->ctx, &path, stbuf);
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|                     if (err < 0) {
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|                         err = -errno;
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|                     }
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|                 }
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|                 v9fs_path_free(&path);
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| /* Only works with path name based fid */
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| int v9fs_co_remove(V9fsPDU *pdu, V9fsPath *path)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->remove(&s->ctx, path->data);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| int v9fs_co_unlinkat(V9fsPDU *pdu, V9fsPath *path, V9fsString *name, int flags)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->unlinkat(&s->ctx, path, name->data, flags);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| /* Only work with path name based fid */
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| int v9fs_co_rename(V9fsPDU *pdu, V9fsPath *oldpath, V9fsPath *newpath)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->rename(&s->ctx, oldpath->data, newpath->data);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     return err;
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| }
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| 
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| int v9fs_co_renameat(V9fsPDU *pdu, V9fsPath *olddirpath, V9fsString *oldname,
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|                      V9fsPath *newdirpath, V9fsString *newname)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->renameat(&s->ctx, olddirpath, oldname->data,
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|                                    newdirpath, newname->data);
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|             if (err < 0) {
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|                 err = -errno;
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|             }
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|         });
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|     return err;
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| }
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| 
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| int v9fs_co_symlink(V9fsPDU *pdu, V9fsFidState *dfidp, V9fsString *name,
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|                     const char *oldpath, gid_t gid, struct stat *stbuf)
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| {
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|     int err;
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|     FsCred cred;
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|     V9fsPath path;
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|     V9fsState *s = pdu->s;
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| 
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|     if (v9fs_request_cancelled(pdu)) {
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|         return -EINTR;
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|     }
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|     cred_init(&cred);
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|     cred.fc_uid = dfidp->uid;
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|     cred.fc_gid = gid;
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|     cred.fc_mode = 0777;
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|     v9fs_path_read_lock(s);
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|     v9fs_co_run_in_worker(
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|         {
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|             err = s->ops->symlink(&s->ctx, oldpath, &dfidp->path,
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|                                   name->data, &cred);
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|             if (err < 0) {
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|                 err = -errno;
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|             } else {
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|                 v9fs_path_init(&path);
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|                 err = v9fs_name_to_path(s, &dfidp->path, name->data, &path);
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|                 if (!err) {
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|                     err = s->ops->lstat(&s->ctx, &path, stbuf);
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|                     if (err < 0) {
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|                         err = -errno;
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|                     }
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|                 }
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|                 v9fs_path_free(&path);
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|             }
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|         });
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|     v9fs_path_unlock(s);
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|     return err;
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| }
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| 
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| /*
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|  * For path name based fid we don't block. So we can
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|  * directly call the fs driver ops.
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|  */
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| int v9fs_co_name_to_path(V9fsPDU *pdu, V9fsPath *dirpath,
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|                          const char *name, V9fsPath *path)
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| {
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|     int err;
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|     V9fsState *s = pdu->s;
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| 
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|     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
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|         err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
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|         if (err < 0) {
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|             err = -errno;
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|         }
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|     } else {
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|         if (v9fs_request_cancelled(pdu)) {
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|             return -EINTR;
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|         }
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|         v9fs_co_run_in_worker(
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|             {
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|                 err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
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|                 if (err < 0) {
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|                     err = -errno;
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|                 }
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|             });
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|     }
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|     return err;
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| }
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