/* * ifile.c - NILFS inode file * * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * Written by Amagai Yoshiji. * Revised by Ryusuke Konishi. * */ #include #include #include "nilfs.h" #include "mdt.h" #include "alloc.h" #include "ifile.h" /** * struct nilfs_ifile_info - on-memory private data of ifile * @mi: on-memory private data of metadata file * @palloc_cache: persistent object allocator cache of ifile */ struct nilfs_ifile_info { struct nilfs_mdt_info mi; struct nilfs_palloc_cache palloc_cache; }; static inline struct nilfs_ifile_info *NILFS_IFILE_I(struct inode *ifile) { return (struct nilfs_ifile_info *)NILFS_MDT(ifile); } /** * nilfs_ifile_create_inode - create a new disk inode * @ifile: ifile inode * @out_ino: pointer to a variable to store inode number * @out_bh: buffer_head contains newly allocated disk inode * * Return Value: On success, 0 is returned and the newly allocated inode * number is stored in the place pointed by @ino, and buffer_head pointer * that contains newly allocated disk inode structure is stored in the * place pointed by @out_bh * On error, one of the following negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. * * %-ENOSPC - No inode left. */ int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino, struct buffer_head **out_bh) { struct nilfs_palloc_req req; int ret; req.pr_entry_nr = 0; /* * 0 says find free inode from beginning * of a group. dull code!! */ req.pr_entry_bh = NULL; ret = nilfs_palloc_prepare_alloc_entry(ifile, &req); if (!ret) { ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1, &req.pr_entry_bh); if (ret < 0) nilfs_palloc_abort_alloc_entry(ifile, &req); } if (ret < 0) { brelse(req.pr_entry_bh); return ret; } nilfs_palloc_commit_alloc_entry(ifile, &req); mark_buffer_dirty(req.pr_entry_bh); nilfs_mdt_mark_dirty(ifile); *out_ino = (ino_t)req.pr_entry_nr; *out_bh = req.pr_entry_bh; return 0; } /** * nilfs_ifile_delete_inode - delete a disk inode * @ifile: ifile inode * @ino: inode number * * Return Value: On success, 0 is returned. On error, one of the following * negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. * * %-ENOENT - The inode number @ino have not been allocated. */ int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino) { struct nilfs_palloc_req req = { .pr_entry_nr = ino, .pr_entry_bh = NULL }; struct nilfs_inode *raw_inode; void *kaddr; int ret; ret = nilfs_palloc_prepare_free_entry(ifile, &req); if (!ret) { ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0, &req.pr_entry_bh); if (ret < 0) nilfs_palloc_abort_free_entry(ifile, &req); } if (ret < 0) { brelse(req.pr_entry_bh); return ret; } kaddr = kmap_atomic(req.pr_entry_bh->b_page); raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr, req.pr_entry_bh, kaddr); raw_inode->i_flags = 0; kunmap_atomic(kaddr); mark_buffer_dirty(req.pr_entry_bh); brelse(req.pr_entry_bh); nilfs_palloc_commit_free_entry(ifile, &req); return 0; } int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino, struct buffer_head **out_bh) { struct super_block *sb = ifile->i_sb; int err; if (unlikely(!NILFS_VALID_INODE(sb, ino))) { nilfs_error(sb, "bad inode number: %lu", (unsigned long)ino); return -EINVAL; } err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh); if (unlikely(err)) nilfs_msg(sb, KERN_WARNING, "error %d reading inode: ino=%lu", err, (unsigned long)ino); return err; } /** * nilfs_ifile_count_free_inodes - calculate free inodes count * @ifile: ifile inode * @nmaxinodes: current maximum of available inodes count [out] * @nfreeinodes: free inodes count [out] */ int nilfs_ifile_count_free_inodes(struct inode *ifile, u64 *nmaxinodes, u64 *nfreeinodes) { u64 nused; int err; *nmaxinodes = 0; *nfreeinodes = 0; nused = atomic64_read(&NILFS_I(ifile)->i_root->inodes_count); err = nilfs_palloc_count_max_entries(ifile, nused, nmaxinodes); if (likely(!err)) *nfreeinodes = *nmaxinodes - nused; return err; } /** * nilfs_ifile_read - read or get ifile inode * @sb: super block instance * @root: root object * @inode_size: size of an inode * @raw_inode: on-disk ifile inode * @inodep: buffer to store the inode */ int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root, size_t inode_size, struct nilfs_inode *raw_inode, struct inode **inodep) { struct inode *ifile; int err; ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO); if (unlikely(!ifile)) return -ENOMEM; if (!(ifile->i_state & I_NEW)) goto out; err = nilfs_mdt_init(ifile, NILFS_MDT_GFP, sizeof(struct nilfs_ifile_info)); if (err) goto failed; err = nilfs_palloc_init_blockgroup(ifile, inode_size); if (err) goto failed; nilfs_palloc_setup_cache(ifile, &NILFS_IFILE_I(ifile)->palloc_cache); err = nilfs_read_inode_common(ifile, raw_inode); if (err) goto failed; unlock_new_inode(ifile); out: *inodep = ifile; return 0; failed: iget_failed(ifile); return err; } lpc32xx-clock.h?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>patch) tree960f5ca6342ad20837aff18aad6e8ecd7da32fd6 /include/dt-bindings/clock/lpc32xx-clock.h 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 'include/dt-bindings/clock/lpc32xx-clock.h')