From 03dd4cb26d967f9588437b0fc9cc0e8353322bb7 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Fri, 25 Mar 2016 03:53:42 -0300 Subject: Linux-libre 4.5-gnu --- fs/configfs/configfs_internal.h | 14 ++- fs/configfs/dir.c | 222 +++++++++++++++++++++++++--------- fs/configfs/file.c | 259 ++++++++++++++++++++++++++++++++++++++-- fs/configfs/inode.c | 6 +- fs/configfs/symlink.c | 22 ++-- 5 files changed, 442 insertions(+), 81 deletions(-) (limited to 'fs/configfs') diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h index b65d1ef53..ccc31fa6f 100644 --- a/fs/configfs/configfs_internal.h +++ b/fs/configfs/configfs_internal.h @@ -53,13 +53,14 @@ struct configfs_dirent { #define CONFIGFS_ROOT 0x0001 #define CONFIGFS_DIR 0x0002 #define CONFIGFS_ITEM_ATTR 0x0004 +#define CONFIGFS_ITEM_BIN_ATTR 0x0008 #define CONFIGFS_ITEM_LINK 0x0020 #define CONFIGFS_USET_DIR 0x0040 #define CONFIGFS_USET_DEFAULT 0x0080 #define CONFIGFS_USET_DROPPING 0x0100 #define CONFIGFS_USET_IN_MKDIR 0x0200 #define CONFIGFS_USET_CREATING 0x0400 -#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) +#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR) extern struct mutex configfs_symlink_mutex; extern spinlock_t configfs_dirent_lock; @@ -72,6 +73,8 @@ extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, extern int configfs_create(struct dentry *, umode_t mode, void (*init)(struct inode *)); extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); +extern int configfs_create_bin_file(struct config_item *, + const struct configfs_bin_attribute *); extern int configfs_make_dirent(struct configfs_dirent *, struct dentry *, void *, umode_t, int); extern int configfs_dirent_is_ready(struct configfs_dirent *); @@ -88,7 +91,7 @@ extern void configfs_release_fs(void); extern struct rw_semaphore configfs_rename_sem; extern const struct file_operations configfs_dir_operations; extern const struct file_operations configfs_file_operations; -extern const struct file_operations bin_fops; +extern const struct file_operations configfs_bin_file_operations; extern const struct inode_operations configfs_dir_inode_operations; extern const struct inode_operations configfs_root_inode_operations; extern const struct inode_operations configfs_symlink_inode_operations; @@ -119,6 +122,13 @@ static inline struct configfs_attribute * to_attr(struct dentry * dentry) return ((struct configfs_attribute *) sd->s_element); } +static inline struct configfs_bin_attribute *to_bin_attr(struct dentry *dentry) +{ + struct configfs_attribute *attr = to_attr(dentry); + + return container_of(attr, struct configfs_bin_attribute, cb_attr); +} + static inline struct config_item *configfs_get_config_item(struct dentry *dentry) { struct config_item * item = NULL; diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index a7a1b218f..f419519ec 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -255,6 +255,12 @@ static void configfs_init_file(struct inode * inode) inode->i_fop = &configfs_file_operations; } +static void configfs_init_bin_file(struct inode *inode) +{ + inode->i_size = 0; + inode->i_fop = &configfs_bin_file_operations; +} + static void init_symlink(struct inode * inode) { inode->i_op = &configfs_symlink_inode_operations; @@ -423,7 +429,9 @@ static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * den spin_unlock(&configfs_dirent_lock); error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG, - configfs_init_file); + (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) ? + configfs_init_bin_file : + configfs_init_file); if (error) { configfs_put(sd); return error; @@ -583,6 +591,7 @@ static int populate_attrs(struct config_item *item) { struct config_item_type *t = item->ci_type; struct configfs_attribute *attr; + struct configfs_bin_attribute *bin_attr; int error = 0; int i; @@ -594,6 +603,13 @@ static int populate_attrs(struct config_item *item) break; } } + if (t->ct_bin_attrs) { + for (i = 0; (bin_attr = t->ct_bin_attrs[i]) != NULL; i++) { + error = configfs_create_bin_file(item, bin_attr); + if (error) + break; + } + } if (error) detach_attrs(item); @@ -624,13 +640,13 @@ static void detach_groups(struct config_group *group) child = sd->s_dentry; - mutex_lock(&d_inode(child)->i_mutex); + inode_lock(d_inode(child)); configfs_detach_group(sd->s_element); d_inode(child)->i_flags |= S_DEAD; dont_mount(child); - mutex_unlock(&d_inode(child)->i_mutex); + inode_unlock(d_inode(child)); d_delete(child); dput(child); @@ -818,11 +834,11 @@ static int configfs_attach_item(struct config_item *parent_item, * the VFS may already have hit and used them. Thus, * we must lock them as rmdir() would. */ - mutex_lock(&d_inode(dentry)->i_mutex); + inode_lock(d_inode(dentry)); configfs_remove_dir(item); d_inode(dentry)->i_flags |= S_DEAD; dont_mount(dentry); - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); d_delete(dentry); } } @@ -858,7 +874,7 @@ static int configfs_attach_group(struct config_item *parent_item, * We must also lock the inode to remove it safely in case of * error, as rmdir() would. */ - mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_CHILD); + inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD); configfs_adjust_dir_dirent_depth_before_populate(sd); ret = populate_groups(to_config_group(item)); if (ret) { @@ -867,7 +883,7 @@ static int configfs_attach_group(struct config_item *parent_item, dont_mount(dentry); } configfs_adjust_dir_dirent_depth_after_populate(sd); - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); if (ret) d_delete(dentry); } @@ -1054,11 +1070,55 @@ out: return ret; } +static int configfs_do_depend_item(struct dentry *subsys_dentry, + struct config_item *target) +{ + struct configfs_dirent *p; + int ret; + + spin_lock(&configfs_dirent_lock); + /* Scan the tree, return 0 if found */ + ret = configfs_depend_prep(subsys_dentry, target); + if (ret) + goto out_unlock_dirent_lock; + + /* + * We are sure that the item is not about to be removed by rmdir(), and + * not in the middle of attachment by mkdir(). + */ + p = target->ci_dentry->d_fsdata; + p->s_dependent_count += 1; + +out_unlock_dirent_lock: + spin_unlock(&configfs_dirent_lock); + + return ret; +} + +static inline struct configfs_dirent * +configfs_find_subsys_dentry(struct configfs_dirent *root_sd, + struct config_item *subsys_item) +{ + struct configfs_dirent *p; + struct configfs_dirent *ret = NULL; + + list_for_each_entry(p, &root_sd->s_children, s_sibling) { + if (p->s_type & CONFIGFS_DIR && + p->s_element == subsys_item) { + ret = p; + break; + } + } + + return ret; +} + + int configfs_depend_item(struct configfs_subsystem *subsys, struct config_item *target) { int ret; - struct configfs_dirent *p, *root_sd, *subsys_sd = NULL; + struct configfs_dirent *subsys_sd; struct config_item *s_item = &subsys->su_group.cg_item; struct dentry *root; @@ -1075,43 +1135,19 @@ int configfs_depend_item(struct configfs_subsystem *subsys, * subsystem is really registered, and so we need to lock out * configfs_[un]register_subsystem(). */ - mutex_lock(&d_inode(root)->i_mutex); - - root_sd = root->d_fsdata; - - list_for_each_entry(p, &root_sd->s_children, s_sibling) { - if (p->s_type & CONFIGFS_DIR) { - if (p->s_element == s_item) { - subsys_sd = p; - break; - } - } - } + inode_lock(d_inode(root)); + subsys_sd = configfs_find_subsys_dentry(root->d_fsdata, s_item); if (!subsys_sd) { ret = -ENOENT; goto out_unlock_fs; } /* Ok, now we can trust subsys/s_item */ + ret = configfs_do_depend_item(subsys_sd->s_dentry, target); - spin_lock(&configfs_dirent_lock); - /* Scan the tree, return 0 if found */ - ret = configfs_depend_prep(subsys_sd->s_dentry, target); - if (ret) - goto out_unlock_dirent_lock; - - /* - * We are sure that the item is not about to be removed by rmdir(), and - * not in the middle of attachment by mkdir(). - */ - p = target->ci_dentry->d_fsdata; - p->s_dependent_count += 1; - -out_unlock_dirent_lock: - spin_unlock(&configfs_dirent_lock); out_unlock_fs: - mutex_unlock(&d_inode(root)->i_mutex); + inode_unlock(d_inode(root)); /* * If we succeeded, the fs is pinned via other methods. If not, @@ -1128,8 +1164,7 @@ EXPORT_SYMBOL(configfs_depend_item); * configfs_depend_item() because we know that that the client driver is * pinned, thus the subsystem is pinned, and therefore configfs is pinned. */ -void configfs_undepend_item(struct configfs_subsystem *subsys, - struct config_item *target) +void configfs_undepend_item(struct config_item *target) { struct configfs_dirent *sd; @@ -1152,6 +1187,79 @@ void configfs_undepend_item(struct configfs_subsystem *subsys, } EXPORT_SYMBOL(configfs_undepend_item); +/* + * caller_subsys is a caller's subsystem not target's. This is used to + * determine if we should lock root and check subsys or not. When we are + * in the same subsystem as our target there is no need to do locking as + * we know that subsys is valid and is not unregistered during this function + * as we are called from callback of one of his children and VFS holds a lock + * on some inode. Otherwise we have to lock our root to ensure that target's + * subsystem it is not unregistered during this function. + */ +int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys, + struct config_item *target) +{ + struct configfs_subsystem *target_subsys; + struct config_group *root, *parent; + struct configfs_dirent *subsys_sd; + int ret = -ENOENT; + + /* Disallow this function for configfs root */ + if (configfs_is_root(target)) + return -EINVAL; + + parent = target->ci_group; + /* + * This may happen when someone is trying to depend root + * directory of some subsystem + */ + if (configfs_is_root(&parent->cg_item)) { + target_subsys = to_configfs_subsystem(to_config_group(target)); + root = parent; + } else { + target_subsys = parent->cg_subsys; + /* Find a cofnigfs root as we may need it for locking */ + for (root = parent; !configfs_is_root(&root->cg_item); + root = root->cg_item.ci_group) + ; + } + + if (target_subsys != caller_subsys) { + /* + * We are in other configfs subsystem, so we have to do + * additional locking to prevent other subsystem from being + * unregistered + */ + inode_lock(d_inode(root->cg_item.ci_dentry)); + + /* + * As we are trying to depend item from other subsystem + * we have to check if this subsystem is still registered + */ + subsys_sd = configfs_find_subsys_dentry( + root->cg_item.ci_dentry->d_fsdata, + &target_subsys->su_group.cg_item); + if (!subsys_sd) + goto out_root_unlock; + } else { + subsys_sd = target_subsys->su_group.cg_item.ci_dentry->d_fsdata; + } + + /* Now we can execute core of depend item */ + ret = configfs_do_depend_item(subsys_sd->s_dentry, target); + + if (target_subsys != caller_subsys) +out_root_unlock: + /* + * We were called from subsystem other than our target so we + * took some locks so now it's time to release them + */ + inode_unlock(d_inode(root->cg_item.ci_dentry)); + + return ret; +} +EXPORT_SYMBOL(configfs_depend_item_unlocked); + static int configfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { int ret = 0; @@ -1453,7 +1561,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name) down_write(&configfs_rename_sem); parent = item->parent->dentry; - mutex_lock(&d_inode(parent)->i_mutex); + inode_lock(d_inode(parent)); new_dentry = lookup_one_len(new_name, parent, strlen(new_name)); if (!IS_ERR(new_dentry)) { @@ -1469,7 +1577,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name) error = -EEXIST; dput(new_dentry); } - mutex_unlock(&d_inode(parent)->i_mutex); + inode_unlock(d_inode(parent)); up_write(&configfs_rename_sem); return error; @@ -1482,7 +1590,7 @@ static int configfs_dir_open(struct inode *inode, struct file *file) struct configfs_dirent * parent_sd = dentry->d_fsdata; int err; - mutex_lock(&d_inode(dentry)->i_mutex); + inode_lock(d_inode(dentry)); /* * Fake invisibility if dir belongs to a group/default groups hierarchy * being attached @@ -1495,7 +1603,7 @@ static int configfs_dir_open(struct inode *inode, struct file *file) else err = 0; } - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); return err; } @@ -1505,11 +1613,11 @@ static int configfs_dir_close(struct inode *inode, struct file *file) struct dentry * dentry = file->f_path.dentry; struct configfs_dirent * cursor = file->private_data; - mutex_lock(&d_inode(dentry)->i_mutex); + inode_lock(d_inode(dentry)); spin_lock(&configfs_dirent_lock); list_del_init(&cursor->s_sibling); spin_unlock(&configfs_dirent_lock); - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); release_configfs_dirent(cursor); @@ -1590,7 +1698,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence) { struct dentry * dentry = file->f_path.dentry; - mutex_lock(&d_inode(dentry)->i_mutex); + inode_lock(d_inode(dentry)); switch (whence) { case 1: offset += file->f_pos; @@ -1598,7 +1706,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence) if (offset >= 0) break; default: - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); return -EINVAL; } if (offset != file->f_pos) { @@ -1624,7 +1732,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence) spin_unlock(&configfs_dirent_lock); } } - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); return offset; } @@ -1659,14 +1767,14 @@ int configfs_register_group(struct config_group *parent_group, parent = parent_group->cg_item.ci_dentry; - mutex_lock_nested(&d_inode(parent)->i_mutex, I_MUTEX_PARENT); + inode_lock_nested(d_inode(parent), I_MUTEX_PARENT); ret = create_default_group(parent_group, group); if (!ret) { spin_lock(&configfs_dirent_lock); configfs_dir_set_ready(group->cg_item.ci_dentry->d_fsdata); spin_unlock(&configfs_dirent_lock); } - mutex_unlock(&d_inode(parent)->i_mutex); + inode_unlock(d_inode(parent)); return ret; } EXPORT_SYMBOL(configfs_register_group); @@ -1683,7 +1791,7 @@ void configfs_unregister_group(struct config_group *group) struct dentry *dentry = group->cg_item.ci_dentry; struct dentry *parent = group->cg_item.ci_parent->ci_dentry; - mutex_lock_nested(&d_inode(parent)->i_mutex, I_MUTEX_PARENT); + inode_lock_nested(d_inode(parent), I_MUTEX_PARENT); spin_lock(&configfs_dirent_lock); configfs_detach_prep(dentry, NULL); spin_unlock(&configfs_dirent_lock); @@ -1692,7 +1800,7 @@ void configfs_unregister_group(struct config_group *group) d_inode(dentry)->i_flags |= S_DEAD; dont_mount(dentry); d_delete(dentry); - mutex_unlock(&d_inode(parent)->i_mutex); + inode_unlock(d_inode(parent)); dput(dentry); @@ -1764,7 +1872,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys) sd = root->d_fsdata; link_group(to_config_group(sd->s_element), group); - mutex_lock_nested(&d_inode(root)->i_mutex, I_MUTEX_PARENT); + inode_lock_nested(d_inode(root), I_MUTEX_PARENT); err = -ENOMEM; dentry = d_alloc_name(root, group->cg_item.ci_name); @@ -1784,7 +1892,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys) } } - mutex_unlock(&d_inode(root)->i_mutex); + inode_unlock(d_inode(root)); if (err) { unlink_group(group); @@ -1805,9 +1913,9 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys) return; } - mutex_lock_nested(&d_inode(root)->i_mutex, + inode_lock_nested(d_inode(root), I_MUTEX_PARENT); - mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_CHILD); + inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD); mutex_lock(&configfs_symlink_mutex); spin_lock(&configfs_dirent_lock); if (configfs_detach_prep(dentry, NULL)) { @@ -1818,11 +1926,11 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys) configfs_detach_group(&group->cg_item); d_inode(dentry)->i_flags |= S_DEAD; dont_mount(dentry); - mutex_unlock(&d_inode(dentry)->i_mutex); + inode_unlock(d_inode(dentry)); d_delete(dentry); - mutex_unlock(&d_inode(root)->i_mutex); + inode_unlock(d_inode(root)); dput(dentry); diff --git a/fs/configfs/file.c b/fs/configfs/file.c index d39099ea7..33b7ee34e 100644 --- a/fs/configfs/file.c +++ b/fs/configfs/file.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -48,6 +49,10 @@ struct configfs_buffer { struct configfs_item_operations * ops; struct mutex mutex; int needs_read_fill; + bool read_in_progress; + bool write_in_progress; + char *bin_buffer; + int bin_buffer_size; }; @@ -123,6 +128,87 @@ out: return retval; } +/** + * configfs_read_bin_file - read a binary attribute. + * @file: file pointer. + * @buf: buffer to fill. + * @count: number of bytes to read. + * @ppos: starting offset in file. + * + * Userspace wants to read a binary attribute file. The attribute + * descriptor is in the file's ->d_fsdata. The target item is in the + * directory's ->d_fsdata. + * + * We check whether we need to refill the buffer. If so we will + * call the attributes' attr->read() twice. The first time we + * will pass a NULL as a buffer pointer, which the attributes' method + * will use to return the size of the buffer required. If no error + * occurs we will allocate the buffer using vmalloc and call + * attr->read() again passing that buffer as an argument. + * Then we just copy to user-space using simple_read_from_buffer. + */ + +static ssize_t +configfs_read_bin_file(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct configfs_buffer *buffer = file->private_data; + struct dentry *dentry = file->f_path.dentry; + struct config_item *item = to_item(dentry->d_parent); + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + ssize_t retval = 0; + ssize_t len = min_t(size_t, count, PAGE_SIZE); + + mutex_lock(&buffer->mutex); + + /* we don't support switching read/write modes */ + if (buffer->write_in_progress) { + retval = -ETXTBSY; + goto out; + } + buffer->read_in_progress = 1; + + if (buffer->needs_read_fill) { + /* perform first read with buf == NULL to get extent */ + len = bin_attr->read(item, NULL, 0); + if (len <= 0) { + retval = len; + goto out; + } + + /* do not exceed the maximum value */ + if (bin_attr->cb_max_size && len > bin_attr->cb_max_size) { + retval = -EFBIG; + goto out; + } + + buffer->bin_buffer = vmalloc(len); + if (buffer->bin_buffer == NULL) { + retval = -ENOMEM; + goto out; + } + buffer->bin_buffer_size = len; + + /* perform second read to fill buffer */ + len = bin_attr->read(item, buffer->bin_buffer, len); + if (len < 0) { + retval = len; + vfree(buffer->bin_buffer); + buffer->bin_buffer_size = 0; + buffer->bin_buffer = NULL; + goto out; + } + + buffer->needs_read_fill = 0; + } + + retval = simple_read_from_buffer(buf, count, ppos, buffer->bin_buffer, + buffer->bin_buffer_size); +out: + mutex_unlock(&buffer->mutex); + return retval; +} + /** * fill_write_buffer - copy buffer from userspace. @@ -209,10 +295,80 @@ configfs_write_file(struct file *file, const char __user *buf, size_t count, lof return len; } -static int check_perm(struct inode * inode, struct file * file) +/** + * configfs_write_bin_file - write a binary attribute. + * @file: file pointer + * @buf: data to write + * @count: number of bytes + * @ppos: starting offset + * + * Writing to a binary attribute file is similar to a normal read. + * We buffer the consecutive writes (binary attribute files do not + * support lseek) in a continuously growing buffer, but we don't + * commit until the close of the file. + */ + +static ssize_t +configfs_write_bin_file(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct configfs_buffer *buffer = file->private_data; + struct dentry *dentry = file->f_path.dentry; + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + void *tbuf = NULL; + ssize_t len; + + mutex_lock(&buffer->mutex); + + /* we don't support switching read/write modes */ + if (buffer->read_in_progress) { + len = -ETXTBSY; + goto out; + } + buffer->write_in_progress = 1; + + /* buffer grows? */ + if (*ppos + count > buffer->bin_buffer_size) { + + if (bin_attr->cb_max_size && + *ppos + count > bin_attr->cb_max_size) { + len = -EFBIG; + } + + tbuf = vmalloc(*ppos + count); + if (tbuf == NULL) { + len = -ENOMEM; + goto out; + } + + /* copy old contents */ + if (buffer->bin_buffer) { + memcpy(tbuf, buffer->bin_buffer, + buffer->bin_buffer_size); + vfree(buffer->bin_buffer); + } + + /* clear the new area */ + memset(tbuf + buffer->bin_buffer_size, 0, + *ppos + count - buffer->bin_buffer_size); + buffer->bin_buffer = tbuf; + buffer->bin_buffer_size = *ppos + count; + } + + len = simple_write_to_buffer(buffer->bin_buffer, + buffer->bin_buffer_size, ppos, buf, count); + if (len > 0) + *ppos += len; +out: + mutex_unlock(&buffer->mutex); + return len; +} + +static int check_perm(struct inode * inode, struct file * file, int type) { struct config_item *item = configfs_get_config_item(file->f_path.dentry->d_parent); struct configfs_attribute * attr = to_attr(file->f_path.dentry); + struct configfs_bin_attribute *bin_attr = NULL; struct configfs_buffer * buffer; struct configfs_item_operations * ops = NULL; int error = 0; @@ -220,6 +376,9 @@ static int check_perm(struct inode * inode, struct file * file) if (!item || !attr) goto Einval; + if (type & CONFIGFS_ITEM_BIN_ATTR) + bin_attr = to_bin_attr(file->f_path.dentry); + /* Grab the module reference for this attribute if we have one */ if (!try_module_get(attr->ca_owner)) { error = -ENODEV; @@ -236,9 +395,14 @@ static int check_perm(struct inode * inode, struct file * file) * and we must have a store method. */ if (file->f_mode & FMODE_WRITE) { - if (!(inode->i_mode & S_IWUGO) || !attr->store) + if (!(inode->i_mode & S_IWUGO)) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_ATTR) && !attr->store) goto Eaccess; + if ((type & CONFIGFS_ITEM_BIN_ATTR) && !bin_attr->write) + goto Eaccess; } /* File needs read support. @@ -246,7 +410,13 @@ static int check_perm(struct inode * inode, struct file * file) * must be a show method for it. */ if (file->f_mode & FMODE_READ) { - if (!(inode->i_mode & S_IRUGO) || !attr->show) + if (!(inode->i_mode & S_IRUGO)) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_ATTR) && !attr->show) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_BIN_ATTR) && !bin_attr->read) goto Eaccess; } @@ -260,6 +430,8 @@ static int check_perm(struct inode * inode, struct file * file) } mutex_init(&buffer->mutex); buffer->needs_read_fill = 1; + buffer->read_in_progress = 0; + buffer->write_in_progress = 0; buffer->ops = ops; file->private_data = buffer; goto Done; @@ -277,12 +449,7 @@ static int check_perm(struct inode * inode, struct file * file) return error; } -static int configfs_open_file(struct inode * inode, struct file * filp) -{ - return check_perm(inode,filp); -} - -static int configfs_release(struct inode * inode, struct file * filp) +static int configfs_release(struct inode *inode, struct file *filp) { struct config_item * item = to_item(filp->f_path.dentry->d_parent); struct configfs_attribute * attr = to_attr(filp->f_path.dentry); @@ -303,6 +470,47 @@ static int configfs_release(struct inode * inode, struct file * filp) return 0; } +static int configfs_open_file(struct inode *inode, struct file *filp) +{ + return check_perm(inode, filp, CONFIGFS_ITEM_ATTR); +} + +static int configfs_open_bin_file(struct inode *inode, struct file *filp) +{ + return check_perm(inode, filp, CONFIGFS_ITEM_BIN_ATTR); +} + +static int configfs_release_bin_file(struct inode *inode, struct file *filp) +{ + struct configfs_buffer *buffer = filp->private_data; + struct dentry *dentry = filp->f_path.dentry; + struct config_item *item = to_item(dentry->d_parent); + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + ssize_t len = 0; + int ret; + + buffer->read_in_progress = 0; + + if (buffer->write_in_progress) { + buffer->write_in_progress = 0; + + len = bin_attr->write(item, buffer->bin_buffer, + buffer->bin_buffer_size); + + /* vfree on NULL is safe */ + vfree(buffer->bin_buffer); + buffer->bin_buffer = NULL; + buffer->bin_buffer_size = 0; + buffer->needs_read_fill = 1; + } + + ret = configfs_release(inode, filp); + if (len < 0) + return len; + return ret; +} + + const struct file_operations configfs_file_operations = { .read = configfs_read_file, .write = configfs_write_file, @@ -311,6 +519,14 @@ const struct file_operations configfs_file_operations = { .release = configfs_release, }; +const struct file_operations configfs_bin_file_operations = { + .read = configfs_read_bin_file, + .write = configfs_write_bin_file, + .llseek = NULL, /* bin file is not seekable */ + .open = configfs_open_bin_file, + .release = configfs_release_bin_file, +}; + /** * configfs_create_file - create an attribute file for an item. * @item: item we're creating for. @@ -324,11 +540,32 @@ int configfs_create_file(struct config_item * item, const struct configfs_attrib umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG; int error = 0; - mutex_lock_nested(&d_inode(dir)->i_mutex, I_MUTEX_NORMAL); + inode_lock_nested(d_inode(dir), I_MUTEX_NORMAL); error = configfs_make_dirent(parent_sd, NULL, (void *) attr, mode, CONFIGFS_ITEM_ATTR); - mutex_unlock(&d_inode(dir)->i_mutex); + inode_unlock(d_inode(dir)); return error; } +/** + * configfs_create_bin_file - create a binary attribute file for an item. + * @item: item we're creating for. + * @attr: atrribute descriptor. + */ + +int configfs_create_bin_file(struct config_item *item, + const struct configfs_bin_attribute *bin_attr) +{ + struct dentry *dir = item->ci_dentry; + struct configfs_dirent *parent_sd = dir->d_fsdata; + umode_t mode = (bin_attr->cb_attr.ca_mode & S_IALLUGO) | S_IFREG; + int error = 0; + + inode_lock_nested(dir->d_inode, I_MUTEX_NORMAL); + error = configfs_make_dirent(parent_sd, NULL, (void *) bin_attr, mode, + CONFIGFS_ITEM_BIN_ATTR); + inode_unlock(dir->d_inode); + + return error; +} diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c index eae87575e..cee087d8f 100644 --- a/fs/configfs/inode.c +++ b/fs/configfs/inode.c @@ -218,7 +218,7 @@ const unsigned char * configfs_get_name(struct configfs_dirent *sd) if (sd->s_type & (CONFIGFS_DIR | CONFIGFS_ITEM_LINK)) return sd->s_dentry->d_name.name; - if (sd->s_type & CONFIGFS_ITEM_ATTR) { + if (sd->s_type & (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)) { attr = sd->s_element; return attr->ca_name; } @@ -255,7 +255,7 @@ void configfs_hash_and_remove(struct dentry * dir, const char * name) /* no inode means this hasn't been made visible yet */ return; - mutex_lock(&d_inode(dir)->i_mutex); + inode_lock(d_inode(dir)); list_for_each_entry(sd, &parent_sd->s_children, s_sibling) { if (!sd->s_element) continue; @@ -268,5 +268,5 @@ void configfs_hash_and_remove(struct dentry * dir, const char * name) break; } } - mutex_unlock(&d_inode(dir)->i_mutex); + inode_unlock(d_inode(dir)); } diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c index ec5c8325b..db6d69289 100644 --- a/fs/configfs/symlink.c +++ b/fs/configfs/symlink.c @@ -279,27 +279,33 @@ static int configfs_getlink(struct dentry *dentry, char * path) } -static const char *configfs_follow_link(struct dentry *dentry, void **cookie) +static const char *configfs_get_link(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) { - unsigned long page = get_zeroed_page(GFP_KERNEL); + char *body; int error; - if (!page) + if (!dentry) + return ERR_PTR(-ECHILD); + + body = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (!body) return ERR_PTR(-ENOMEM); - error = configfs_getlink(dentry, (char *)page); + error = configfs_getlink(dentry, body); if (!error) { - return *cookie = (void *)page; + set_delayed_call(done, kfree_link, body); + return body; } - free_page(page); + kfree(body); return ERR_PTR(error); } const struct inode_operations configfs_symlink_inode_operations = { - .follow_link = configfs_follow_link, + .get_link = configfs_get_link, .readlink = generic_readlink, - .put_link = free_page_put_link, .setattr = configfs_setattr, }; -- cgit v1.2.3-54-g00ecf