/**************************************************************************** * fs/tmpfs/fs_tmpfs.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "fs_tmpfs.h" #ifndef CONFIG_DISABLE_MOUNTPOINT /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #if CONFIG_FS_TMPFS_DIRECTORY_FREEGUARD <= CONFIG_FS_TMPFS_DIRECTORY_ALLOCGUARD # warning CONFIG_FS_TMPFS_DIRECTORY_FREEGUARD needs to be > ALLOCGUARD #endif #if CONFIG_FS_TMPFS_FILE_FREEGUARD <= CONFIG_FS_TMPFS_FILE_ALLOCGUARD # warning CONFIG_FS_TMPFS_FILE_FREEGUARD needs to be > ALLOCGUARD #endif #define tmpfs_lock_file(tfo) \ (tmpfs_lock_object((FAR struct tmpfs_object_s *)tfo)) #define tmpfs_lock_directory(tdo) \ (tmpfs_lock_object((FAR struct tmpfs_object_s *)tdo)) #define tmpfs_unlock_file(tfo) \ (tmpfs_unlock_object((FAR struct tmpfs_object_s *)tfo)) #define tmpfs_unlock_directory(tdo) \ (tmpfs_unlock_object((FAR struct tmpfs_object_s *)tdo)) /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* TMPFS helpers */ static int tmpfs_lock_reentrant(FAR struct tmpfs_sem_s *sem); static int tmpfs_lock(FAR struct tmpfs_s *fs); static void tmpfs_unlock_reentrant(FAR struct tmpfs_sem_s *sem); static void tmpfs_unlock(FAR struct tmpfs_s *fs); static int tmpfs_lock_object(FAR struct tmpfs_object_s *to); static void tmpfs_unlock_object(FAR struct tmpfs_object_s *to); static int tmpfs_realloc_directory(FAR struct tmpfs_directory_s **tdo, unsigned int nentries); static int tmpfs_realloc_file(FAR struct tmpfs_file_s **tfo, size_t newsize); static void tmpfs_release_lockedobject(FAR struct tmpfs_object_s *to); static void tmpfs_release_lockedfile(FAR struct tmpfs_file_s *tfo); static int tmpfs_find_dirent(FAR struct tmpfs_directory_s *tdo, FAR const char *name); static int tmpfs_remove_dirent(FAR struct tmpfs_directory_s *tdo, FAR const char *name); static int tmpfs_add_dirent(FAR struct tmpfs_directory_s **tdo, FAR struct tmpfs_object_s *to, FAR const char *name); static FAR struct tmpfs_file_s *tmpfs_alloc_file(void); static int tmpfs_create_file(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_file_s **tfo); static FAR struct tmpfs_directory_s *tmpfs_alloc_directory(void); static int tmpfs_create_directory(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_directory_s **tdo); static int tmpfs_find_object(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_object_s **object, FAR struct tmpfs_directory_s **parent); static int tmpfs_find_file(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_file_s **tfo, FAR struct tmpfs_directory_s **parent); static int tmpfs_find_directory(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_directory_s **tdo, FAR struct tmpfs_directory_s **parent); static int tmpfs_statfs_callout(FAR struct tmpfs_directory_s *tdo, unsigned int index, FAR void *arg); static int tmpfs_free_callout(FAR struct tmpfs_directory_s *tdo, unsigned int index, FAR void *arg); static int tmpfs_foreach(FAR struct tmpfs_directory_s *tdo, tmpfs_foreach_t callout, FAR void *arg); /* File system operations */ static int tmpfs_open(FAR struct file *filep, FAR const char *relpath, int oflags, mode_t mode); static int tmpfs_close(FAR struct file *filep); static ssize_t tmpfs_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static ssize_t tmpfs_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); static off_t tmpfs_seek(FAR struct file *filep, off_t offset, int whence); static int tmpfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg); static int tmpfs_dup(FAR const struct file *oldp, FAR struct file *newp); static int tmpfs_fstat(FAR const struct file *filep, FAR struct stat *buf); static int tmpfs_truncate(FAR struct file *filep, off_t length); static int tmpfs_opendir(FAR struct inode *mountpt, FAR const char *relpath, FAR struct fs_dirent_s *dir); static int tmpfs_closedir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir); static int tmpfs_readdir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir); static int tmpfs_rewinddir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir); static int tmpfs_bind(FAR struct inode *blkdriver, FAR const void *data, FAR void **handle); static int tmpfs_unbind(FAR void *handle, FAR struct inode **blkdriver, unsigned int flags); static int tmpfs_statfs(FAR struct inode *mountpt, FAR struct statfs *buf); static int tmpfs_unlink(FAR struct inode *mountpt, FAR const char *relpath); static int tmpfs_mkdir(FAR struct inode *mountpt, FAR const char *relpath, mode_t mode); static int tmpfs_rmdir(FAR struct inode *mountpt, FAR const char *relpath); static int tmpfs_rename(FAR struct inode *mountpt, FAR const char *oldrelpath, FAR const char *newrelpath); static void tmpfs_stat_common(FAR struct tmpfs_object_s *to, FAR struct stat *buf); static int tmpfs_stat(FAR struct inode *mountpt, FAR const char *relpath, FAR struct stat *buf); /**************************************************************************** * Public Data ****************************************************************************/ const struct mountpt_operations tmpfs_operations = { tmpfs_open, /* open */ tmpfs_close, /* close */ tmpfs_read, /* read */ tmpfs_write, /* write */ tmpfs_seek, /* seek */ tmpfs_ioctl, /* ioctl */ NULL, /* sync */ tmpfs_dup, /* dup */ tmpfs_fstat, /* fstat */ tmpfs_truncate, /* truncate */ tmpfs_opendir, /* opendir */ tmpfs_closedir, /* closedir */ tmpfs_readdir, /* readdir */ tmpfs_rewinddir, /* rewinddir */ tmpfs_bind, /* bind */ tmpfs_unbind, /* unbind */ tmpfs_statfs, /* statfs */ tmpfs_unlink, /* unlink */ tmpfs_mkdir, /* mkdir */ tmpfs_rmdir, /* rmdir */ tmpfs_rename, /* rename */ tmpfs_stat, /* stat */ }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: tmpfs_lock_reentrant ****************************************************************************/ static int tmpfs_lock_reentrant(FAR struct tmpfs_sem_s *sem) { pid_t me; int ret = OK; /* Do we already hold the semaphore? */ me = getpid(); if (me == sem->ts_holder) { /* Yes... just increment the count */ sem->ts_count++; DEBUGASSERT(sem->ts_count > 0); } /* Take the semaphore (perhaps waiting) */ else { ret = nxsem_wait_uninterruptible(&sem->ts_sem); if (ret >= 0) { /* No we hold the semaphore */ sem->ts_holder = me; sem->ts_count = 1; } } return ret; } /**************************************************************************** * Name: tmpfs_lock ****************************************************************************/ static int tmpfs_lock(FAR struct tmpfs_s *fs) { return tmpfs_lock_reentrant(&fs->tfs_exclsem); } /**************************************************************************** * Name: tmpfs_lock_object ****************************************************************************/ static int tmpfs_lock_object(FAR struct tmpfs_object_s *to) { return tmpfs_lock_reentrant(&to->to_exclsem); } /**************************************************************************** * Name: tmpfs_unlock_reentrant ****************************************************************************/ static void tmpfs_unlock_reentrant(FAR struct tmpfs_sem_s *sem) { DEBUGASSERT(sem->ts_holder == getpid()); /* Is this our last count on the semaphore? */ if (sem->ts_count > 1) { /* No.. just decrement the count */ sem->ts_count--; } /* Yes.. then we can really release the semaphore */ else { sem->ts_holder = TMPFS_NO_HOLDER; sem->ts_count = 0; nxsem_post(&sem->ts_sem); } } /**************************************************************************** * Name: tmpfs_unlock ****************************************************************************/ static void tmpfs_unlock(FAR struct tmpfs_s *fs) { tmpfs_unlock_reentrant(&fs->tfs_exclsem); } /**************************************************************************** * Name: tmpfs_unlock_object ****************************************************************************/ static void tmpfs_unlock_object(FAR struct tmpfs_object_s *to) { tmpfs_unlock_reentrant(&to->to_exclsem); } /**************************************************************************** * Name: tmpfs_realloc_directory ****************************************************************************/ static int tmpfs_realloc_directory(FAR struct tmpfs_directory_s **tdo, unsigned int nentries) { FAR struct tmpfs_directory_s *oldtdo = *tdo; FAR struct tmpfs_directory_s *newtdo; size_t objsize; int ret = oldtdo->tdo_nentries; /* Get the new object size */ objsize = SIZEOF_TMPFS_DIRECTORY(nentries); if (objsize <= oldtdo->tdo_alloc) { /* Already big enough. * REVISIT: Missing logic to shrink directory objects. */ oldtdo->tdo_nentries = nentries; return ret; } /* Added some additional amount to the new size to account frequent * reallocations. */ objsize += CONFIG_FS_TMPFS_DIRECTORY_ALLOCGUARD; /* Realloc the directory object */ newtdo = (FAR struct tmpfs_directory_s *)kmm_realloc(oldtdo, objsize); if (newtdo == NULL) { return -ENOMEM; } /* Adjust the reference in the parent directory entry */ DEBUGASSERT(newtdo->tdo_dirent); newtdo->tdo_dirent->tde_object = (FAR struct tmpfs_object_s *)newtdo; /* Return the new address of the reallocated directory object */ newtdo->tdo_alloc = objsize; newtdo->tdo_nentries = nentries; *tdo = newtdo; /* Adjust the reference in the parent directory entry */ DEBUGASSERT(newtdo->tdo_dirent); newtdo->tdo_dirent->tde_object = (FAR struct tmpfs_object_s *)newtdo; /* Return the index to the first, newly allocated directory entry */ return ret; } /**************************************************************************** * Name: tmpfs_realloc_file ****************************************************************************/ static int tmpfs_realloc_file(FAR struct tmpfs_file_s **tfo, size_t newsize) { FAR struct tmpfs_file_s *oldtfo = *tfo; FAR struct tmpfs_file_s *newtfo; size_t objsize; size_t allocsize; size_t delta; /* Check if the current allocation is sufficient */ objsize = SIZEOF_TMPFS_FILE(newsize); /* Are we growing or shrinking the object? */ if (objsize <= oldtfo->tfo_alloc) { /* Shrinking ... Shrink unconditionally if the size is shrinking to * zero. */ if (newsize > 0) { /* Otherwise, don't realloc unless the object has shrunk by a * lot. */ delta = oldtfo->tfo_alloc - objsize; if (delta <= CONFIG_FS_TMPFS_FILE_FREEGUARD) { /* Hasn't shrunk enough.. Return doing nothing for now */ oldtfo->tfo_size = newsize; return OK; } } } /* Added some additional amount to the new size to account frequent * reallocations. */ allocsize = objsize + CONFIG_FS_TMPFS_FILE_ALLOCGUARD; /* Realloc the file object */ newtfo = (FAR struct tmpfs_file_s *)kmm_realloc(oldtfo, allocsize); if (newtfo == NULL) { return -ENOMEM; } /* Adjust the reference in the parent directory entry */ DEBUGASSERT(newtfo->tfo_dirent); newtfo->tfo_dirent->tde_object = (FAR struct tmpfs_object_s *)newtfo; /* Return the new address of the reallocated file object */ newtfo->tfo_alloc = allocsize; newtfo->tfo_size = newsize; *tfo = newtfo; return OK; } /**************************************************************************** * Name: tmpfs_release_lockedobject ****************************************************************************/ static void tmpfs_release_lockedobject(FAR struct tmpfs_object_s *to) { DEBUGASSERT(to && to->to_refs > 0); /* Is this a file object? */ if (to->to_type == TMPFS_REGULAR) { tmpfs_release_lockedfile((FAR struct tmpfs_file_s *)to); } else { to->to_refs--; tmpfs_unlock_object(to); } } /**************************************************************************** * Name: tmpfs_release_lockedfile ****************************************************************************/ static void tmpfs_release_lockedfile(FAR struct tmpfs_file_s *tfo) { DEBUGASSERT(tfo && tfo->tfo_refs > 0); /* If there are no longer any references to the file and the file has been * unlinked from its parent directory, then free the file object now. */ if (tfo->tfo_refs == 1 && (tfo->tfo_flags & TFO_FLAG_UNLINKED) != 0) { nxsem_destroy(&tfo->tfo_exclsem.ts_sem); kmm_free(tfo); } /* Otherwise, just decrement the reference count on the file object */ else { tfo->tfo_refs--; tmpfs_unlock_file(tfo); } } /**************************************************************************** * Name: tmpfs_find_dirent ****************************************************************************/ static int tmpfs_find_dirent(FAR struct tmpfs_directory_s *tdo, FAR const char *name) { int i; /* Search the list of directory entries for a match */ for (i = 0; i < tdo->tdo_nentries && strcmp(tdo->tdo_entry[i].tde_name, name) != 0; i++); /* Return what we found, if anything */ return i < tdo->tdo_nentries ? i : -ENOENT; } /**************************************************************************** * Name: tmpfs_remove_dirent ****************************************************************************/ static int tmpfs_remove_dirent(FAR struct tmpfs_directory_s *tdo, FAR const char *name) { int index; int last; /* Search the list of directory entries for a match */ index = tmpfs_find_dirent(tdo, name); if (index < 0) { return index; } /* Free the object name */ if (tdo->tdo_entry[index].tde_name != NULL) { kmm_free(tdo->tdo_entry[index].tde_name); } /* Remove by replacing this entry with the final directory entry */ last = tdo->tdo_nentries - 1; if (index != last) { FAR struct tmpfs_dirent_s *newtde; FAR struct tmpfs_dirent_s *oldtde; FAR struct tmpfs_object_s *to; /* Move the directory entry */ newtde = &tdo->tdo_entry[index]; oldtde = &tdo->tdo_entry[last]; to = oldtde->tde_object; newtde->tde_object = to; newtde->tde_name = oldtde->tde_name; /* Reset the backward link to the directory entry */ to->to_dirent = newtde; } /* And decrement the count of directory entries */ tdo->tdo_nentries = last; return OK; } /**************************************************************************** * Name: tmpfs_add_dirent ****************************************************************************/ static int tmpfs_add_dirent(FAR struct tmpfs_directory_s **tdo, FAR struct tmpfs_object_s *to, FAR const char *name) { FAR struct tmpfs_directory_s *oldtdo; FAR struct tmpfs_directory_s *newtdo; FAR struct tmpfs_dirent_s *tde; FAR char *newname; unsigned int nentries; int index; /* Copy the name string so that it will persist as long as the * directory entry. */ newname = strdup(name); if (newname == NULL) { return -ENOMEM; } /* Get the new number of entries */ oldtdo = *tdo; nentries = oldtdo->tdo_nentries + 1; /* Reallocate the directory object (if necessary) */ index = tmpfs_realloc_directory(tdo, nentries); if (index < 0) { kmm_free(newname); return index; } /* Save the new object info in the new directory entry */ newtdo = *tdo; tde = &newtdo->tdo_entry[index]; tde->tde_object = to; tde->tde_name = newname; /* Add backward link to the directory entry to the object */ to->to_dirent = tde; return OK; } /**************************************************************************** * Name: tmpfs_alloc_file ****************************************************************************/ static FAR struct tmpfs_file_s *tmpfs_alloc_file(void) { FAR struct tmpfs_file_s *tfo; size_t allocsize; /* Create a new zero length file object */ allocsize = SIZEOF_TMPFS_FILE(CONFIG_FS_TMPFS_FILE_ALLOCGUARD); tfo = (FAR struct tmpfs_file_s *)kmm_malloc(allocsize); if (tfo == NULL) { return NULL; } /* Initialize the new file object. NOTE that the initial state is * locked with one reference count. */ tfo->tfo_alloc = allocsize; tfo->tfo_type = TMPFS_REGULAR; tfo->tfo_refs = 1; tfo->tfo_flags = 0; tfo->tfo_size = 0; tfo->tfo_exclsem.ts_holder = getpid(); tfo->tfo_exclsem.ts_count = 1; nxsem_init(&tfo->tfo_exclsem.ts_sem, 0, 0); return tfo; } /**************************************************************************** * Name: tmpfs_create_file ****************************************************************************/ static int tmpfs_create_file(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_file_s **tfo) { FAR struct tmpfs_directory_s *parent; FAR struct tmpfs_file_s *newtfo; FAR char *copy; FAR char *name; int ret; /* Duplicate the path variable so that we can modify it */ copy = strdup(relpath); if (copy == NULL) { return -ENOMEM; } /* Separate the path into the file name and the path to the parent * directory. */ name = strrchr(copy, '/'); if (name == NULL) { /* No subdirectories... use the root directory */ name = copy; parent = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; /* Lock the root directory to emulate the behavior of tmpfs_find_directory() */ ret = tmpfs_lock_directory(parent); if (ret < 0) { kmm_free(copy); return ret; } parent->tdo_refs++; } else { /* Terminate the parent directory path */ *name++ = '\0'; /* Locate the parent directory that should contain this name. * On success, tmpfs_find_directory() will lock the parent * directory and increment the reference count. */ ret = tmpfs_find_directory(fs, copy, &parent, NULL); if (ret < 0) { goto errout_with_copy; } } /* Verify that no object of this name already exists in the directory */ ret = tmpfs_find_dirent(parent, name); if (ret != -ENOENT) { /* Something with this name already exists in the directory. * OR perhaps some fatal error occurred. */ if (ret >= 0) { ret = -EEXIST; } goto errout_with_parent; } /* Allocate an empty file. The initial state of the file is locked with * one reference count. */ newtfo = tmpfs_alloc_file(); if (newtfo == NULL) { ret = -ENOMEM; goto errout_with_parent; } /* Then add the new, empty file to the directory */ ret = tmpfs_add_dirent(&parent, (FAR struct tmpfs_object_s *)newtfo, name); if (ret < 0) { goto errout_with_file; } /* Release the reference and lock on the parent directory */ parent->tdo_refs--; tmpfs_unlock_directory(parent); /* Free the copy of the relpath and return success */ kmm_free(copy); *tfo = newtfo; return OK; /* Error exits */ errout_with_file: nxsem_destroy(&newtfo->tfo_exclsem.ts_sem); kmm_free(newtfo); errout_with_parent: parent->tdo_refs--; tmpfs_unlock_directory(parent); errout_with_copy: kmm_free(copy); return ret; } /**************************************************************************** * Name: tmpfs_alloc_directory ****************************************************************************/ static FAR struct tmpfs_directory_s *tmpfs_alloc_directory(void) { FAR struct tmpfs_directory_s *tdo; size_t allocsize; unsigned int nentries; /* Convert the pre-allocated memory to a number of directory entries */ nentries = (CONFIG_FS_TMPFS_DIRECTORY_ALLOCGUARD + sizeof(struct tmpfs_dirent_s) - 1) / sizeof(struct tmpfs_dirent_s); /* Create a new zero length directory object */ allocsize = SIZEOF_TMPFS_DIRECTORY(nentries); tdo = (FAR struct tmpfs_directory_s *)kmm_malloc(allocsize); if (tdo == NULL) { return NULL; } /* Initialize the new directory object */ tdo->tdo_alloc = allocsize; tdo->tdo_type = TMPFS_DIRECTORY; tdo->tdo_refs = 0; tdo->tdo_nentries = 0; tdo->tdo_exclsem.ts_holder = TMPFS_NO_HOLDER; tdo->tdo_exclsem.ts_count = 0; nxsem_init(&tdo->tdo_exclsem.ts_sem, 0, 1); return tdo; } /**************************************************************************** * Name: tmpfs_create_directory ****************************************************************************/ static int tmpfs_create_directory(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_directory_s **tdo) { FAR struct tmpfs_directory_s *parent; FAR struct tmpfs_directory_s *newtdo; FAR char *copy; FAR char *name; int ret; /* Duplicate the path variable so that we can modify it */ copy = strdup(relpath); if (copy == NULL) { return -ENOMEM; } /* Separate the path into the file name and the path to the parent * directory. */ name = strrchr(copy, '/'); if (name == NULL) { /* No subdirectories... use the root directory */ name = copy; parent = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; ret = tmpfs_lock_directory(parent); if (ret < 0) { kmm_free(copy); return ret; } parent->tdo_refs++; } else { /* Terminate the parent directory path */ *name++ = '\0'; /* Locate the parent directory that should contain this name. * On success, tmpfs_find_directory() will lockthe parent * directory and increment the reference count. */ ret = tmpfs_find_directory(fs, copy, &parent, NULL); if (ret < 0) { goto errout_with_copy; } } /* Verify that no object of this name already exists in the directory */ ret = tmpfs_find_dirent(parent, name); if (ret != -ENOENT) { /* Something with this name already exists in the directory. * OR perhaps some fatal error occurred. */ if (ret >= 0) { ret = -EEXIST; } goto errout_with_parent; } /* Allocate an empty directory object. NOTE that there is no reference on * the new directory and the object is not locked. */ newtdo = tmpfs_alloc_directory(); if (newtdo == NULL) { ret = -ENOMEM; goto errout_with_parent; } /* Then add the new, empty file to the directory */ ret = tmpfs_add_dirent(&parent, (FAR struct tmpfs_object_s *)newtdo, name); if (ret < 0) { goto errout_with_directory; } /* Free the copy of the relpath, release our reference to the parent * directory, and return success */ parent->tdo_refs--; tmpfs_unlock_directory(parent); kmm_free(copy); /* Return the (unlocked, unreferenced) directory object to the caller */ if (tdo != NULL) { *tdo = newtdo; } return OK; /* Error exits */ errout_with_directory: nxsem_destroy(&newtdo->tdo_exclsem.ts_sem); kmm_free(newtdo); errout_with_parent: parent->tdo_refs--; tmpfs_unlock_directory(parent); errout_with_copy: kmm_free(copy); return ret; } /**************************************************************************** * Name: tmpfs_find_object ****************************************************************************/ static int tmpfs_find_object(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_object_s **object, FAR struct tmpfs_directory_s **parent) { FAR struct tmpfs_object_s *to = NULL; FAR struct tmpfs_directory_s *tdo = NULL; FAR struct tmpfs_directory_s *next_tdo; FAR char *segment; FAR char *next_segment; FAR char *tkptr; FAR char *copy; int index; int ret; /* Make a copy of the path (so that we can modify it via strtok) */ copy = strdup(relpath); if (copy == NULL) { return -ENOMEM; } /* Traverse the file system for any object with the matching name */ to = fs->tfs_root.tde_object; next_tdo = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; for (segment = strtok_r(copy, "/", &tkptr); segment != NULL; segment = next_segment) { /* Get the next segment after the one we are currently working on. * This will be NULL is we are working on the final segment of the * relpath. */ next_segment = strtok_r(NULL, "/", &tkptr); /* Search the next directory. */ tdo = next_tdo; /* Find the TMPFS object with the next segment name in the current * directory. */ index = tmpfs_find_dirent(tdo, segment); if (index < 0) { /* No object with this name exists in the directory. */ kmm_free(copy); return index; } to = tdo->tdo_entry[index].tde_object; /* Is this object another directory? */ if (to->to_type != TMPFS_DIRECTORY) { /* No. Was this the final segment in the path? */ if (next_segment == NULL) { /* Then we can break out of the loop now */ break; } /* No, this was not the final segment of the relpath. * We cannot continue the search if any of the intermediate * segments do no correspond to directories. */ kmm_free(copy); return -ENOTDIR; } /* Search this directory for the next segment. If we * exit the loop, tdo will still refer to the parent * directory of to. */ next_tdo = (FAR struct tmpfs_directory_s *)to; } /* When we exit this loop (successfully), to will point to the TMPFS * object associated with the terminal segment of the relpath. * Increment the reference count on the located object. */ /* Free the dup'ed string */ kmm_free(copy); /* Return what we found */ if (parent) { if (tdo != NULL) { /* Get exclusive access to the parent and increment the reference * count on the object. */ ret = tmpfs_lock_directory(tdo); if (ret < 0) { return ret; } tdo->tdo_refs++; } *parent = tdo; } if (object) { if (to != NULL) { /* Get exclusive access to the object and increment the reference * count on the object. */ ret = tmpfs_lock_object(to); if (ret < 0) { return ret; } to->to_refs++; } *object = to; } return OK; } /**************************************************************************** * Name: tmpfs_find_file ****************************************************************************/ static int tmpfs_find_file(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_file_s **tfo, FAR struct tmpfs_directory_s **parent) { FAR struct tmpfs_object_s *to; int ret; /* Find the object at this path. If successful, tmpfs_find_object() will * lock both the object and the parent directory and will increment the * reference count on both. */ ret = tmpfs_find_object(fs, relpath, &to, parent); if (ret >= 0) { /* We found it... but is it a regular file? */ if (to->to_type != TMPFS_REGULAR) { /* No... unlock the object and its parent and return an error */ tmpfs_release_lockedobject(to); if (parent) { FAR struct tmpfs_directory_s *tdo = *parent; tdo->tdo_refs--; tmpfs_unlock_directory(tdo); } ret = -EISDIR; } /* Return the verified file object */ *tfo = (FAR struct tmpfs_file_s *)to; } return ret; } /**************************************************************************** * Name: tmpfs_find_directory ****************************************************************************/ static int tmpfs_find_directory(FAR struct tmpfs_s *fs, FAR const char *relpath, FAR struct tmpfs_directory_s **tdo, FAR struct tmpfs_directory_s **parent) { FAR struct tmpfs_object_s *to; int ret; /* Find the object at this path */ ret = tmpfs_find_object(fs, relpath, &to, parent); if (ret >= 0) { /* We found it... but is it a regular file? */ if (to->to_type != TMPFS_DIRECTORY) { /* No... unlock the object and its parent and return an error */ tmpfs_release_lockedobject(to); if (parent) { FAR struct tmpfs_directory_s *tmptdo = *parent; tmptdo->tdo_refs--; tmpfs_unlock_directory(tmptdo); } ret = -ENOTDIR; } /* Return the verified file object */ *tdo = (FAR struct tmpfs_directory_s *)to; } return ret; } /**************************************************************************** * Name: tmpfs_statfs_callout ****************************************************************************/ static int tmpfs_statfs_callout(FAR struct tmpfs_directory_s *tdo, unsigned int index, FAR void *arg) { FAR struct tmpfs_object_s *to; FAR struct tmpfs_statfs_s *tmpbuf; DEBUGASSERT(tdo != NULL && arg != NULL && index < tdo->tdo_nentries); to = tdo->tdo_entry[index].tde_object; tmpbuf = (FAR struct tmpfs_statfs_s *)arg; DEBUGASSERT(to != NULL); /* Accumulate statistics. Save the total memory allocated for this object. */ tmpbuf->tsf_alloc += to->to_alloc; /* Is this directory entry a file object? */ if (to->to_type == TMPFS_REGULAR) { FAR struct tmpfs_file_s *tmptfo; /* It is a file object. Increment the number of files and update the * amount of memory in use. */ tmptfo = (FAR struct tmpfs_file_s *)to; tmpbuf->tsf_inuse += tmptfo->tfo_size; tmpbuf->tsf_files++; } else /* if (to->to_type == TMPFS_DIRECTORY) */ { FAR struct tmpfs_directory_s *tmptdo; size_t inuse; size_t avail; /* It is a directory object. Update the amount of memory in use * for the directory and estimate the number of free directory nodes. */ tmptdo = (FAR struct tmpfs_directory_s *)to; inuse = SIZEOF_TMPFS_DIRECTORY(tmptdo->tdo_nentries); avail = tmptdo->tdo_alloc - inuse; tmpbuf->tsf_inuse += inuse; tmpbuf->tsf_ffree += avail / sizeof(struct tmpfs_dirent_s); } return TMPFS_CONTINUE; } /**************************************************************************** * Name: tmpfs_free_callout ****************************************************************************/ static int tmpfs_free_callout(FAR struct tmpfs_directory_s *tdo, unsigned int index, FAR void *arg) { FAR struct tmpfs_dirent_s *tde; FAR struct tmpfs_object_s *to; FAR struct tmpfs_file_s *tfo; unsigned int last; /* Free the object name */ if (tdo->tdo_entry[index].tde_name != NULL) { kmm_free(tdo->tdo_entry[index].tde_name); } /* Remove by replacing this entry with the final directory entry */ tde = &tdo->tdo_entry[index]; to = tde->tde_object; last = tdo->tdo_nentries - 1; if (index != last) { FAR struct tmpfs_dirent_s *oldtde; FAR struct tmpfs_object_s *oldto; /* Move the directory entry */ oldtde = &tdo->tdo_entry[last]; oldto = oldtde->tde_object; tde->tde_object = oldto; tde->tde_name = oldtde->tde_name; /* Reset the backward link to the directory entry */ oldto->to_dirent = tde; } /* And decrement the count of directory entries */ tdo->tdo_nentries = last; /* Is this directory entry a file object? */ if (to->to_type == TMPFS_REGULAR) { tfo = (FAR struct tmpfs_file_s *)to; /* Are there references to the file? */ if (tfo->tfo_refs > 0) { /* Yes.. We cannot delete the file now. Just mark it as unlinked. */ tfo->tfo_flags |= TFO_FLAG_UNLINKED; return TMPFS_UNLINKED; } } /* Free the object now */ nxsem_destroy(&to->to_exclsem.ts_sem); kmm_free(to); return TMPFS_DELETED; } /**************************************************************************** * Name: tmpfs_foreach ****************************************************************************/ static int tmpfs_foreach(FAR struct tmpfs_directory_s *tdo, tmpfs_foreach_t callout, FAR void *arg) { FAR struct tmpfs_object_s *to; unsigned int index; int ret; /* Visit each directory entry */ for (index = 0; index < tdo->tdo_nentries; ) { /* Lock the object and take a reference */ to = tdo->tdo_entry[index].tde_object; ret = tmpfs_lock_object(to); if (ret < 0) { return ret; } to->to_refs++; /* Is the next entry a directory? */ if (to->to_type == TMPFS_DIRECTORY) { FAR struct tmpfs_directory_s *next = (FAR struct tmpfs_directory_s *)to; /* Yes.. traverse its children first in the case the final * action will be to delete the directory. */ ret = tmpfs_foreach(next, callout, arg); if (ret < 0) { return -ECANCELED; } } /* Perform the callout */ ret = callout(tdo, index, arg); switch (ret) { case TMPFS_CONTINUE: /* Continue enumeration */ /* Release the object and index to the next entry */ tmpfs_release_lockedobject(to); index++; break; case TMPFS_HALT: /* Stop enumeration */ /* Release the object and cancel the traversal */ tmpfs_release_lockedobject(to); return -ECANCELED; case TMPFS_UNLINKED: /* Only the directory entry was deleted */ /* Release the object and continue with the same index */ tmpfs_release_lockedobject(to); case TMPFS_DELETED: /* Object and directory entry deleted */ break; /* Continue with the same index */ } } return OK; } /**************************************************************************** * Name: tmpfs_open ****************************************************************************/ static int tmpfs_open(FAR struct file *filep, FAR const char *relpath, int oflags, mode_t mode) { FAR struct inode *inode; FAR struct tmpfs_s *fs; FAR struct tmpfs_file_s *tfo; off_t offset; int ret; finfo("filep: %p\n", filep); DEBUGASSERT(filep->f_priv == NULL && filep->f_inode != NULL); /* Get the mountpoint inode reference from the file structure and the * mountpoint private data from the inode structure */ inode = filep->f_inode; fs = inode->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Skip over any leading directory separators (shouldn't be any) */ for (; *relpath == '/'; relpath++); /* Find the file object associated with this relative path. * If successful, this action will lock both the parent directory and * the file object, adding one to the reference count of both. * In the event that -ENOENT, there will still be a reference and * lock on the returned directory. */ ret = tmpfs_find_file(fs, relpath, &tfo, NULL); if (ret >= 0) { /* The file exists. We hold the lock and one reference count * on the file object. * * It would be an error if we are asked to create it exclusively */ if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) { /* Already exists -- can't create it exclusively */ ret = -EEXIST; goto errout_with_filelock; } /* Check if the caller has sufficient privileges to open the file. * REVISIT: No file protection implemented */ /* If O_TRUNC is specified and the file is opened for writing, * then truncate the file. This operation requires that the file is * writeable, but we have already checked that. O_TRUNC without write * access is ignored. */ if ((oflags & (O_TRUNC | O_WRONLY)) == (O_TRUNC | O_WRONLY)) { /* Truncate the file to zero length (if it is not already * zero length) */ if (tfo->tfo_size > 0) { ret = tmpfs_realloc_file(&tfo, 0); if (ret < 0) { goto errout_with_filelock; } } } } /* ENOENT would be returned by tmpfs_find_file() if the full directory * path was found, but the file was not found in the final directory. */ else if (ret == -ENOENT) { /* The file does not exist. Were we asked to create it? */ if ((oflags & O_CREAT) == 0) { /* No.. then we fail with -ENOENT */ ret = -ENOENT; goto errout_with_fslock; } /* Yes.. create the file object. There will be a reference and a lock * on the new file object. */ ret = tmpfs_create_file(fs, relpath, &tfo); if (ret < 0) { goto errout_with_fslock; } } /* Some other error occurred */ else { goto errout_with_fslock; } /* Save the struct tmpfs_file_s instance as the file private data */ filep->f_priv = tfo; /* In write/append mode, we need to set the file pointer to the end of the * file. */ offset = 0; if ((oflags & (O_APPEND | O_WRONLY)) == (O_APPEND | O_WRONLY)) { offset = tfo->tfo_size; } filep->f_pos = offset; /* Unlock the file file object, but retain the reference count */ tmpfs_unlock_file(tfo); tmpfs_unlock(fs); return OK; /* Error exits */ errout_with_filelock: tmpfs_release_lockedfile(tfo); errout_with_fslock: tmpfs_unlock(fs); return ret; } /**************************************************************************** * Name: tmpfs_close ****************************************************************************/ static int tmpfs_close(FAR struct file *filep) { FAR struct tmpfs_file_s *tfo; int ret; finfo("filep: %p\n", filep); DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; /* Get exclusive access to the file */ ret = tmpfs_lock_file(tfo); if (ret < 0) { return ret; } /* Decrement the reference count on the file */ DEBUGASSERT(tfo->tfo_refs > 0); if (tfo->tfo_refs > 0) { tfo->tfo_refs--; } filep->f_priv = NULL; /* If the reference count decremented to zero and the file has been * unlinked, then free the file allocation now. */ if (tfo->tfo_refs == 0 && (tfo->tfo_flags & TFO_FLAG_UNLINKED) != 0) { /* Free the file object while we hold the lock? Weird but this * should be safe because the object is unlinked and could not * have any other references. */ kmm_free(tfo); return OK; } /* Release the lock on the file */ tmpfs_unlock_file(tfo); return OK; } /**************************************************************************** * Name: tmpfs_read ****************************************************************************/ static ssize_t tmpfs_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { FAR struct tmpfs_file_s *tfo; ssize_t nread; off_t startpos; off_t endpos; int ret; finfo("filep: %p buffer: %p buflen: %lu\n", filep, buffer, (unsigned long)buflen); DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; /* Get exclusive access to the file */ ret = tmpfs_lock_file(tfo); if (ret < 0) { return ret; } /* Handle attempts to read beyond the end of the file. */ startpos = filep->f_pos; nread = buflen; endpos = startpos + buflen; if (endpos > tfo->tfo_size) { endpos = tfo->tfo_size; nread = endpos - startpos; } /* Copy data from the memory object to the user buffer */ memcpy(buffer, &tfo->tfo_data[startpos], nread); filep->f_pos += nread; /* Release the lock on the file */ tmpfs_unlock_file(tfo); return nread; } /**************************************************************************** * Name: tmpfs_write ****************************************************************************/ static ssize_t tmpfs_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { FAR struct tmpfs_file_s *tfo; ssize_t nwritten; off_t startpos; off_t endpos; int ret; finfo("filep: %p buffer: %p buflen: %lu\n", filep, buffer, (unsigned long)buflen); DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; /* Get exclusive access to the file */ ret = tmpfs_lock_file(tfo); if (ret < 0) { return ret; } /* Handle attempts to write beyond the end of the file */ startpos = filep->f_pos; nwritten = buflen; endpos = startpos + buflen; if (endpos > tfo->tfo_size) { /* Reallocate the file to handle the write past the end of the file. */ ret = tmpfs_realloc_file(&tfo, (size_t)endpos); if (ret < 0) { goto errout_with_lock; } filep->f_priv = tfo; } /* Copy data from the memory object to the user buffer */ memcpy(&tfo->tfo_data[startpos], buffer, nwritten); filep->f_pos += nwritten; /* Release the lock on the file */ tmpfs_unlock_file(tfo); return nwritten; errout_with_lock: tmpfs_unlock_file(tfo); return (ssize_t)ret; } /**************************************************************************** * Name: tmpfs_seek ****************************************************************************/ static off_t tmpfs_seek(FAR struct file *filep, off_t offset, int whence) { FAR struct tmpfs_file_s *tfo; off_t position; finfo("filep: %p\n", filep); DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; /* Map the offset according to the whence option */ switch (whence) { case SEEK_SET: /* The offset is set to offset bytes. */ position = offset; break; case SEEK_CUR: /* The offset is set to its current location plus * offset bytes. */ position = offset + filep->f_pos; break; case SEEK_END: /* The offset is set to the size of the file plus * offset bytes. */ position = offset + tfo->tfo_size; break; default: return -EINVAL; } /* Attempts to set the position beyond the end of file will * work if the file is open for write access. * * REVISIT: This simple implementation has no per-open storage that * would be needed to retain the open flags. */ #if 0 if (position > tfo->tfo_size && (tfo->tfo_oflags & O_WROK) == 0) { /* Otherwise, the position is limited to the file size */ position = tfo->tfo_size; } #endif /* Save the new file position */ filep->f_pos = position; return position; } /**************************************************************************** * Name: tmpfs_ioctl ****************************************************************************/ static int tmpfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct tmpfs_file_s *tfo; FAR void **ppv = (FAR void**)arg; finfo("filep: %p cmd: %d arg: %08lx\n", filep, cmd, arg); DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; DEBUGASSERT(tfo != NULL); /* Only one ioctl command is supported */ if (cmd == FIOC_MMAP && ppv != NULL) { /* Return the address on the media corresponding to the start of * the file. */ *ppv = (FAR void *)tfo->tfo_data; return OK; } ferr("ERROR: Invalid cmd: %d\n", cmd); return -ENOTTY; } /**************************************************************************** * Name: tmpfs_dup ****************************************************************************/ static int tmpfs_dup(FAR const struct file *oldp, FAR struct file *newp) { FAR struct tmpfs_file_s *tfo; int ret; finfo("Dup %p->%p\n", oldp, newp); DEBUGASSERT(oldp->f_priv != NULL && oldp->f_inode != NULL && newp->f_priv == NULL && newp->f_inode != NULL); /* Recover our private data from the struct file instance */ tfo = oldp->f_priv; DEBUGASSERT(tfo != NULL); /* Increment the reference count (atomically) */ ret = tmpfs_lock_file(tfo); if (ret >= 0) { tfo->tfo_refs++; tmpfs_unlock_file(tfo); /* Save a copy of the file object as the dup'ed file. This * simple implementation does not many any per-open data * structures so there is not really much to the dup operation. */ newp->f_priv = tfo; ret = OK; } return OK; } /**************************************************************************** * Name: tmpfs_fstat * * Description: * Obtain information about an open file associated with the file * descriptor 'fd', and will write it to the area pointed to by 'buf'. * ****************************************************************************/ static int tmpfs_fstat(FAR const struct file *filep, FAR struct stat *buf) { FAR struct tmpfs_file_s *tfo; int ret; finfo("Fstat %p\n", buf); DEBUGASSERT(filep != NULL && buf != NULL); /* Recover our private data from the struct file instance */ DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); tfo = filep->f_priv; /* Get exclusive access to the file */ ret = tmpfs_lock_file(tfo); if (ret < 0) { return ret; } /* Return information about the file in the stat buffer. */ tmpfs_stat_common((FAR struct tmpfs_object_s *)tfo, buf); /* Release the lock on the file and return success. */ tmpfs_unlock_file(tfo); return OK; } /**************************************************************************** * Name: tmpfs_truncate ****************************************************************************/ static int tmpfs_truncate(FAR struct file *filep, off_t length) { FAR struct tmpfs_file_s *tfo; size_t oldsize; int ret; finfo("filep: %p length: %ld\n", filep, (long)length); DEBUGASSERT(filep != NULL && length >= 0); /* Recover our private data from the struct file instance */ tfo = filep->f_priv; /* Get exclusive access to the file */ ret = tmpfs_lock_file(tfo); if (ret < 0) { return ret; } /* Get the old size of the file. Do nothing if the file size is not * changing. */ oldsize = tfo->tfo_size; if (oldsize != length) { /* The size is changing.. up or down. Reallocate the file memory. */ ret = tmpfs_realloc_file(&tfo, (size_t)length); if (ret < 0) { goto errout_with_lock; } filep->f_priv = tfo; /* If the size has increased, then we need to zero the newly added * memory. */ if (length > oldsize) { memset(&tfo->tfo_data[oldsize], 0, length - oldsize); } ret = OK; } /* Release the lock on the file */ errout_with_lock: tmpfs_unlock_file(tfo); return ret; } /**************************************************************************** * Name: tmpfs_opendir ****************************************************************************/ static int tmpfs_opendir(FAR struct inode *mountpt, FAR const char *relpath, FAR struct fs_dirent_s *dir) { FAR struct tmpfs_s *fs; FAR struct tmpfs_directory_s *tdo; int ret; finfo("mountpt: %p relpath: %s dir: %p\n", mountpt, relpath, dir); DEBUGASSERT(mountpt != NULL && relpath != NULL && dir != NULL); /* Get the mountpoint private data from the inode structure */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Skip over any leading directory separators (shouldn't be any) */ for (; *relpath == '/'; relpath++); /* Find the directory object associated with this relative path. * If successful, this action will lock both the parent directory and * the file object, adding one to the reference count of both. * In the event that -ENOENT, there will still be a reference and * lock on the returned directory. */ ret = tmpfs_find_directory(fs, relpath, &tdo, NULL); if (ret >= 0) { dir->u.tmpfs.tf_tdo = tdo; dir->u.tmpfs.tf_index = 0; tmpfs_unlock_directory(tdo); } /* Release the lock on the file system and return the result */ tmpfs_unlock(fs); return ret; } /**************************************************************************** * Name: tmpfs_closedir ****************************************************************************/ static int tmpfs_closedir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir) { FAR struct tmpfs_directory_s *tdo; finfo("mountpt: %p dir: %p\n", mountpt, dir); DEBUGASSERT(mountpt != NULL && dir != NULL); /* Get the directory structure from the dir argument */ tdo = dir->u.tmpfs.tf_tdo; DEBUGASSERT(tdo != NULL); /* Decrement the reference count on the directory object */ tmpfs_lock_directory(tdo); tdo->tdo_refs--; tmpfs_unlock_directory(tdo); return OK; } /**************************************************************************** * Name: tmpfs_readdir ****************************************************************************/ static int tmpfs_readdir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir) { FAR struct tmpfs_directory_s *tdo; unsigned int index; int ret; finfo("mountpt: %p dir: %p\n", mountpt, dir); DEBUGASSERT(mountpt != NULL && dir != NULL); /* Get the directory structure from the dir argument and lock it */ tdo = dir->u.tmpfs.tf_tdo; DEBUGASSERT(tdo != NULL); tmpfs_lock_directory(tdo); /* Have we reached the end of the directory? */ index = dir->u.tmpfs.tf_index; if (index >= tdo->tdo_nentries) { /* We signal the end of the directory by returning the special error: * -ENOENT */ finfo("End of directory\n"); ret = -ENOENT; } else { FAR struct tmpfs_dirent_s *tde; FAR struct tmpfs_object_s *to; /* Does this entry refer to a file or a directory object? */ tde = &tdo->tdo_entry[index]; to = tde->tde_object; DEBUGASSERT(to != NULL); if (to->to_type == TMPFS_DIRECTORY) { /* A directory */ dir->fd_dir.d_type = DTYPE_DIRECTORY; } else /* to->to_type == TMPFS_REGULAR) */ { /* A regular file */ dir->fd_dir.d_type = DTYPE_FILE; } /* Copy the entry name */ strncpy(dir->fd_dir.d_name, tde->tde_name, NAME_MAX + 1); /* Increment the index for next time */ dir->u.tmpfs.tf_index = index + 1; ret = OK; } tmpfs_unlock_directory(tdo); return ret; } /**************************************************************************** * Name: tmpfs_rewinddir ****************************************************************************/ static int tmpfs_rewinddir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir) { finfo("mountpt: %p dir: %p\n", mountpt, dir); DEBUGASSERT(mountpt != NULL && dir != NULL); /* Set the readdir index to zero */ dir->u.tmpfs.tf_index = 0; return OK; } /**************************************************************************** * Name: tmpfs_bind ****************************************************************************/ static int tmpfs_bind(FAR struct inode *blkdriver, FAR const void *data, FAR void **handle) { FAR struct tmpfs_directory_s *tdo; FAR struct tmpfs_s *fs; finfo("blkdriver: %p data: %p handle: %p\n", blkdriver, data, handle); DEBUGASSERT(blkdriver == NULL && handle != NULL); /* Create an instance of the tmpfs file system */ fs = (FAR struct tmpfs_s *)kmm_zalloc(sizeof(struct tmpfs_s)); if (fs == NULL) { return -ENOMEM; } /* Create a root file system. This is like a single directory entry in * the file system structure. */ tdo = tmpfs_alloc_directory(); if (tdo == NULL) { kmm_free(fs); return -ENOMEM; } fs->tfs_root.tde_object = (FAR struct tmpfs_object_s *)tdo; fs->tfs_root.tde_name = ""; /* Set up the backward link (to support reallocation) */ tdo->tdo_dirent = &fs->tfs_root; /* Initialize the file system state */ fs->tfs_exclsem.ts_holder = TMPFS_NO_HOLDER; fs->tfs_exclsem.ts_count = 0; nxsem_init(&fs->tfs_exclsem.ts_sem, 0, 1); /* Return the new file system handle */ *handle = (FAR void *)fs; return OK; } /**************************************************************************** * Name: tmpfs_unbind ****************************************************************************/ static int tmpfs_unbind(FAR void *handle, FAR struct inode **blkdriver, unsigned int flags) { FAR struct tmpfs_s *fs = (FAR struct tmpfs_s *)handle; FAR struct tmpfs_directory_s *tdo; int ret; finfo("handle: %p blkdriver: %p flags: %02x\n", handle, blkdriver, flags); DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Lock the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Traverse all directory entries (recursively), freeing all resources. */ tdo = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; ret = tmpfs_foreach(tdo, tmpfs_free_callout, NULL); /* Now we can destroy the root file system and the file system itself. */ nxsem_destroy(&tdo->tdo_exclsem.ts_sem); kmm_free(tdo); nxsem_destroy(&fs->tfs_exclsem.ts_sem); kmm_free(fs); return ret; } /**************************************************************************** * Name: tmpfs_statfs ****************************************************************************/ static int tmpfs_statfs(FAR struct inode *mountpt, FAR struct statfs *buf) { FAR struct tmpfs_s *fs; FAR struct tmpfs_directory_s *tdo; struct tmpfs_statfs_s tmpbuf; size_t inuse; size_t avail; off_t blkalloc; off_t blkused; int ret; finfo("mountpt: %p buf: %p\n", mountpt, buf); DEBUGASSERT(mountpt != NULL && buf != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Set up the memory use for the file system and root directory object */ tdo = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; inuse = sizeof(struct tmpfs_s) + SIZEOF_TMPFS_DIRECTORY(tdo->tdo_nentries); avail = sizeof(struct tmpfs_s) + tdo->tdo_alloc - inuse; tmpbuf.tsf_alloc = tdo->tdo_alloc; tmpbuf.tsf_inuse = inuse; tmpbuf.tsf_files = 0; tmpbuf.tsf_ffree = avail / sizeof(struct tmpfs_dirent_s); /* Traverse the file system to accurmulate statistics */ ret = tmpfs_foreach(tdo, tmpfs_statfs_callout, (FAR void *)&tmpbuf); if (ret < 0) { return -ECANCELED; } /* Return something for the file system description */ blkalloc = (tmpbuf.tsf_alloc + CONFIG_FS_TMPFS_BLOCKSIZE - 1) / CONFIG_FS_TMPFS_BLOCKSIZE; blkused = (tmpbuf.tsf_inuse + CONFIG_FS_TMPFS_BLOCKSIZE - 1) / CONFIG_FS_TMPFS_BLOCKSIZE; buf->f_type = TMPFS_MAGIC; buf->f_namelen = NAME_MAX; buf->f_bsize = CONFIG_FS_TMPFS_BLOCKSIZE; buf->f_blocks = blkalloc; buf->f_bfree = blkalloc - blkused; buf->f_bavail = blkalloc - blkused; buf->f_files = tmpbuf.tsf_files; buf->f_ffree = tmpbuf.tsf_ffree; /* Release the lock on the file system */ tmpfs_unlock(fs); return OK; } /**************************************************************************** * Name: tmpfs_unlink ****************************************************************************/ static int tmpfs_unlink(FAR struct inode *mountpt, FAR const char *relpath) { FAR struct tmpfs_s *fs; FAR struct tmpfs_directory_s *tdo; FAR struct tmpfs_file_s *tfo = NULL; FAR const char *name; int ret; finfo("mountpt: %p relpath: %s\n", mountpt, relpath); DEBUGASSERT(mountpt != NULL && relpath != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Find the file object and parent directory associated with this relative * path. If successful, tmpfs_find_file will lock both the file object * and the parent directory and take one reference count on each. */ ret = tmpfs_find_file(fs, relpath, &tfo, &tdo); if (ret < 0) { goto errout_with_lock; } DEBUGASSERT(tfo != NULL); /* Get the file name from the relative path */ name = strrchr(relpath, '/'); if (name != NULL) { /* Skip over the file '/' character */ name++; } else { /* The name must lie in the root directory */ name = relpath; } /* Remove the file from parent directory */ ret = tmpfs_remove_dirent(tdo, name); if (ret < 0) { goto errout_with_objects; } /* If the reference count is not one, then just mark the file as * unlinked */ if (tfo->tfo_refs > 1) { /* Make the file object as unlinked */ tfo->tfo_flags |= TFO_FLAG_UNLINKED; /* Release the reference count on the file object */ tfo->tfo_refs--; tmpfs_unlock_file(tfo); } /* Otherwise we can free the object now */ else { nxsem_destroy(&tfo->tfo_exclsem.ts_sem); kmm_free(tfo); } /* Release the reference and lock on the parent directory */ tdo->tdo_refs--; tmpfs_unlock_directory(tdo); tmpfs_unlock(fs); return OK; errout_with_objects: tmpfs_release_lockedfile(tfo); tdo->tdo_refs--; tmpfs_unlock_directory(tdo); errout_with_lock: tmpfs_unlock(fs); return ret; } /**************************************************************************** * Name: tmpfs_mkdir ****************************************************************************/ static int tmpfs_mkdir(FAR struct inode *mountpt, FAR const char *relpath, mode_t mode) { FAR struct tmpfs_s *fs; int ret; finfo("mountpt: %p relpath: %s mode: %04x\n", mountpt, relpath, mode); DEBUGASSERT(mountpt != NULL && relpath != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Create the directory. */ ret = tmpfs_create_directory(fs, relpath, NULL); tmpfs_unlock(fs); return ret; } /**************************************************************************** * Name: tmpfs_rmdir ****************************************************************************/ static int tmpfs_rmdir(FAR struct inode *mountpt, FAR const char *relpath) { FAR struct tmpfs_s *fs; FAR struct tmpfs_directory_s *parent; FAR struct tmpfs_directory_s *tdo; FAR const char *name; int ret; finfo("mountpt: %p relpath: %s\n", mountpt, relpath); DEBUGASSERT(mountpt != NULL && relpath != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Find the directory object and parent directory associated with this * relative path. If successful, tmpfs_find_file will lock both the * directory object and the parent directory and take one reference count * on each. */ ret = tmpfs_find_directory(fs, relpath, &tdo, &parent); if (ret < 0) { goto errout_with_lock; } /* Is the directory empty? We cannot remove directories that still * contain references to file system objects. No can we remove the * directory if there are outstanding references on it (other than * our reference). */ if (tdo->tdo_nentries > 0 || tdo->tdo_refs > 1) { ret = -EBUSY; goto errout_with_objects; } /* Get the directory name from the relative path */ name = strrchr(relpath, '/'); if (name != NULL) { /* Skip over the fidirectoryle '/' character */ name++; } else { /* The name must lie in the root directory */ name = relpath; } /* Remove the directory from parent directory */ ret = tmpfs_remove_dirent(parent, name); if (ret < 0) { goto errout_with_objects; } /* Free the directory object */ nxsem_destroy(&tdo->tdo_exclsem.ts_sem); kmm_free(tdo); /* Release the reference and lock on the parent directory */ parent->tdo_refs--; tmpfs_unlock_directory(parent); tmpfs_unlock(fs); return OK; errout_with_objects: tdo->tdo_refs--; tmpfs_unlock_directory(tdo); parent->tdo_refs--; tmpfs_unlock_directory(parent); errout_with_lock: tmpfs_unlock(fs); return ret; } /**************************************************************************** * Name: tmpfs_rename ****************************************************************************/ static int tmpfs_rename(FAR struct inode *mountpt, FAR const char *oldrelpath, FAR const char *newrelpath) { FAR struct tmpfs_directory_s *oldparent; FAR struct tmpfs_directory_s *newparent; FAR struct tmpfs_object_s *to; FAR struct tmpfs_s *fs; FAR const char *oldname; FAR char *newname; FAR char *copy; int ret; finfo("mountpt: %p oldrelpath: %s newrelpath: %s\n", mountpt, oldrelpath, newrelpath); DEBUGASSERT(mountpt != NULL && oldrelpath != NULL && newrelpath != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Duplicate the newpath variable so that we can modify it */ copy = strdup(newrelpath); if (copy == NULL) { return -ENOMEM; } /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { kmm_free(copy); return ret; } /* Separate the new path into the new file name and the path to the new * parent directory. */ newname = strrchr(copy, '/'); if (newname == NULL) { /* No subdirectories... use the root directory */ newname = copy; newparent = (FAR struct tmpfs_directory_s *)fs->tfs_root.tde_object; tmpfs_lock_directory(newparent); newparent->tdo_refs++; } else { /* Terminate the parent directory path */ *newname++ = '\0'; /* Locate the parent directory that should contain this name. * On success, tmpfs_find_directory() will lockthe parent * directory and increment the reference count. */ ret = tmpfs_find_directory(fs, copy, &newparent, NULL); if (ret < 0) { goto errout_with_lock; } } /* Verify that no object of this name already exists in the destination * directory. */ ret = tmpfs_find_dirent(newparent, newname); if (ret != -ENOENT) { /* Something with this name already exists in the directory. * OR perhaps some fatal error occurred. */ if (ret >= 0) { ret = -EEXIST; } goto errout_with_newparent; } /* Find the old object at oldpath. If successful, tmpfs_find_object() * will lock both the object and the parent directory and will increment * the reference count on both. */ ret = tmpfs_find_object(fs, oldrelpath, &to, &oldparent); if (ret < 0) { goto errout_with_newparent; } /* Get the old file name from the relative path */ oldname = strrchr(oldrelpath, '/'); if (oldname != NULL) { /* Skip over the file '/' character */ oldname++; } else { /* The name must lie in the root directory */ oldname = oldrelpath; } /* Remove the entry from the parent directory */ ret = tmpfs_remove_dirent(oldparent, oldname); if (ret < 0) { goto errout_with_oldparent; } /* Add an entry to the new parent directory. */ ret = tmpfs_add_dirent(&newparent, to, newname); errout_with_oldparent: oldparent->tdo_refs--; tmpfs_unlock_directory(oldparent); tmpfs_release_lockedobject(to); errout_with_newparent: newparent->tdo_refs--; tmpfs_unlock_directory(newparent); errout_with_lock: tmpfs_unlock(fs); kmm_free(copy); return ret; } /**************************************************************************** * Name: tmpfs_stat_common ****************************************************************************/ static void tmpfs_stat_common(FAR struct tmpfs_object_s *to, FAR struct stat *buf) { size_t objsize; /* Is the tmpfs object a regular file? */ memset(buf, 0, sizeof(struct stat)); if (to->to_type == TMPFS_REGULAR) { FAR struct tmpfs_file_s *tfo = (FAR struct tmpfs_file_s *)to; /* -rwxrwxrwx */ buf->st_mode = S_IRWXO | S_IRWXG | S_IRWXU | S_IFREG; /* Get the size of the object */ objsize = tfo->tfo_size; } else /* if (to->to_type == TMPFS_DIRECTORY) */ { FAR struct tmpfs_directory_s *tdo = (FAR struct tmpfs_directory_s *)to; /* drwxrwxrwx */ buf->st_mode = S_IRWXO | S_IRWXG | S_IRWXU | S_IFDIR; /* Get the size of the object */ objsize = SIZEOF_TMPFS_DIRECTORY(tdo->tdo_nentries); } /* Fake the rest of the information */ buf->st_size = objsize; buf->st_blksize = CONFIG_FS_TMPFS_BLOCKSIZE; buf->st_blocks = (objsize + CONFIG_FS_TMPFS_BLOCKSIZE - 1) / CONFIG_FS_TMPFS_BLOCKSIZE; } /**************************************************************************** * Name: tmpfs_stat ****************************************************************************/ static int tmpfs_stat(FAR struct inode *mountpt, FAR const char *relpath, FAR struct stat *buf) { FAR struct tmpfs_s *fs; FAR struct tmpfs_object_s *to; int ret; finfo("mountpt=%p relpath=%s buf=%p\n", mountpt, relpath, buf); DEBUGASSERT(mountpt != NULL && relpath != NULL && buf != NULL); /* Get the file system structure from the inode reference. */ fs = mountpt->i_private; DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL); /* Get exclusive access to the file system */ ret = tmpfs_lock(fs); if (ret < 0) { return ret; } /* Find the tmpfs object at the relpath. If successful, * tmpfs_find_object() will lock the object and increment the * reference count on the object. */ ret = tmpfs_find_object(fs, relpath, &to, NULL); if (ret < 0) { goto errout_with_fslock; } /* We found it... Return information about the file object in the stat * buffer. */ DEBUGASSERT(to != NULL); tmpfs_stat_common(to, buf); /* Unlock the object and return success */ tmpfs_release_lockedobject(to); ret = OK; errout_with_fslock: tmpfs_unlock(fs); return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ #endif /* CONFIG_DISABLE_MOUNTPOINT */