/* * linux/fs/bad_inode.c * * Copyright (C) 1997, Stephen Tweedie * * Provide stub functions for unreadable inodes * * Fabian Frederick : August 2003 - All file operations assigned to EIO */ #include #include #include #include #include #include static int bad_file_open(struct inode *inode, struct file *filp) { return -EIO; } static const struct file_operations bad_file_ops = { .open = bad_file_open, }; static int bad_inode_create (struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { return -EIO; } static struct dentry *bad_inode_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { return ERR_PTR(-EIO); } static int bad_inode_link (struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { return -EIO; } static int bad_inode_unlink(struct inode *dir, struct dentry *dentry) { return -EIO; } static int bad_inode_symlink (struct inode *dir, struct dentry *dentry, const char *symname) { return -EIO; } static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { return -EIO; } static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry) { return -EIO; } static int bad_inode_mknod (struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) { return -EIO; } static int bad_inode_rename2(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { return -EIO; } static int bad_inode_readlink(struct dentry *dentry, char __user *buffer, int buflen) { return -EIO; } static int bad_inode_permission(struct inode *inode, int mask) { return -EIO; } static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { return -EIO; } static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs) { return -EIO; } static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) { return -EIO; } static const char *bad_inode_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done) { return ERR_PTR(-EIO); } static struct posix_acl *bad_inode_get_acl(struct inode *inode, int type) { return ERR_PTR(-EIO); } static int bad_inode_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len) { return -EIO; } static int bad_inode_update_time(struct inode *inode, struct timespec *time, int flags) { return -EIO; } static int bad_inode_atomic_open(struct inode *inode, struct dentry *dentry, struct file *file, unsigned int open_flag, umode_t create_mode, int *opened) { return -EIO; } static int bad_inode_tmpfile(struct inode *inode, struct dentry *dentry, umode_t mode) { return -EIO; } static int bad_inode_set_acl(struct inode *inode, struct posix_acl *acl, int type) { return -EIO; } static const struct inode_operations bad_inode_ops = { .create = bad_inode_create, .lookup = bad_inode_lookup, .link = bad_inode_link, .unlink = bad_inode_unlink, .symlink = bad_inode_symlink, .mkdir = bad_inode_mkdir, .rmdir = bad_inode_rmdir, .mknod = bad_inode_mknod, .rename = bad_inode_rename2, .readlink = bad_inode_readlink, .permission = bad_inode_permission, .getattr = bad_inode_getattr, .setattr = bad_inode_setattr, .listxattr = bad_inode_listxattr, .get_link = bad_inode_get_link, .get_acl = bad_inode_get_acl, .fiemap = bad_inode_fiemap, .update_time = bad_inode_update_time, .atomic_open = bad_inode_atomic_open, .tmpfile = bad_inode_tmpfile, .set_acl = bad_inode_set_acl, }; /* * When a filesystem is unable to read an inode due to an I/O error in * its read_inode() function, it can call make_bad_inode() to return a * set of stubs which will return EIO errors as required. * * We only need to do limited initialisation: all other fields are * preinitialised to zero automatically. */ /** * make_bad_inode - mark an inode bad due to an I/O error * @inode: Inode to mark bad * * When an inode cannot be read due to a media or remote network * failure this function makes the inode "bad" and causes I/O operations * on it to fail from this point on. */ void make_bad_inode(struct inode *inode) { remove_inode_hash(inode); inode->i_mode = S_IFREG; inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); inode->i_op = &bad_inode_ops; inode->i_opflags &= ~IOP_XATTR; inode->i_fop = &bad_file_ops; } EXPORT_SYMBOL(make_bad_inode); /* * This tests whether an inode has been flagged as bad. The test uses * &bad_inode_ops to cover the case of invalidated inodes as well as * those created by make_bad_inode() above. */ /** * is_bad_inode - is an inode errored * @inode: inode to test * * Returns true if the inode in question has been marked as bad. */ bool is_bad_inode(struct inode *inode) { return (inode->i_op == &bad_inode_ops); } EXPORT_SYMBOL(is_bad_inode); /** * iget_failed - Mark an under-construction inode as dead and release it * @inode: The inode to discard * * Mark an under-construction inode as dead and release it. */ void iget_failed(struct inode *inode) { make_bad_inode(inode); unlock_new_inode(inode); iput(inode); } EXPORT_SYMBOL(iget_failed); a2d530d3b268eef542c5414e54bf1a'>net/rxrpc/local_event.c parent6610d0edf6dc7ee97e46ab3a538a565c79d26199 (diff)
dmaengine: pl330: fix double lock
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'net/rxrpc/local_event.c')