From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- fs/nilfs2/alloc.c | 958 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 958 insertions(+) create mode 100644 fs/nilfs2/alloc.c (limited to 'fs/nilfs2/alloc.c') diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c new file mode 100644 index 000000000..7b1cd2bae --- /dev/null +++ b/fs/nilfs2/alloc.c @@ -0,0 +1,958 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * NILFS dat/inode allocator + * + * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. + * + * Originally written by Koji Sato. + * Two allocators were unified by Ryusuke Konishi and Amagai Yoshiji. + */ + +#include +#include +#include +#include +#include +#include "mdt.h" +#include "alloc.h" + + +/** + * nilfs_palloc_groups_per_desc_block - get the number of groups that a group + * descriptor block can maintain + * @inode: inode of metadata file using this allocator + * + * Return: Number of groups that a group descriptor block can maintain. + */ +static inline unsigned long +nilfs_palloc_groups_per_desc_block(const struct inode *inode) +{ + return i_blocksize(inode) / + sizeof(struct nilfs_palloc_group_desc); +} + +/** + * nilfs_palloc_groups_count - get maximum number of groups + * @inode: inode of metadata file using this allocator + * + * Return: Maximum number of groups. + */ +static inline unsigned long +nilfs_palloc_groups_count(const struct inode *inode) +{ + return 1UL << (BITS_PER_LONG - (inode->i_blkbits + 3 /* log2(8) */)); +} + +/** + * nilfs_palloc_init_blockgroup - initialize private variables for allocator + * @inode: inode of metadata file using this allocator + * @entry_size: size of the persistent object + * + * Return: 0 on success, or a negative error code on failure. + */ +int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned int entry_size) +{ + struct nilfs_mdt_info *mi = NILFS_MDT(inode); + + mi->mi_bgl = kmalloc_obj(*mi->mi_bgl, GFP_NOFS); + if (!mi->mi_bgl) + return -ENOMEM; + + bgl_lock_init(mi->mi_bgl); + + nilfs_mdt_set_entry_size(inode, entry_size, 0); + + mi->mi_blocks_per_group = + DIV_ROUND_UP(nilfs_palloc_entries_per_group(inode), + mi->mi_entries_per_block) + 1; + /* + * Number of blocks in a group including entry blocks + * and a bitmap block + */ + mi->mi_blocks_per_desc_block = + nilfs_palloc_groups_per_desc_block(inode) * + mi->mi_blocks_per_group + 1; + /* + * Number of blocks per descriptor including the + * descriptor block + */ + return 0; +} + +/** + * nilfs_palloc_group - get group number and offset from an entry number + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @offset: pointer to store offset number in the group + * + * Return: Number of the group that contains the entry with the index + * specified by @nr. + */ +static unsigned long nilfs_palloc_group(const struct inode *inode, __u64 nr, + unsigned long *offset) +{ + __u64 group = nr; + + *offset = do_div(group, nilfs_palloc_entries_per_group(inode)); + return group; +} + +/** + * nilfs_palloc_desc_blkoff - get block offset of a group descriptor block + * @inode: inode of metadata file using this allocator + * @group: group number + * + * Return: Index number in the metadata file of the descriptor block of + * the group specified by @group. + */ +static unsigned long +nilfs_palloc_desc_blkoff(const struct inode *inode, unsigned long group) +{ + unsigned long desc_block = + group / nilfs_palloc_groups_per_desc_block(inode); + return desc_block * NILFS_MDT(inode)->mi_blocks_per_desc_block; +} + +/** + * nilfs_palloc_bitmap_blkoff - get block offset of a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + * + * nilfs_palloc_bitmap_blkoff() returns block offset of the bitmap + * block used to allocate/deallocate entries in the specified group. + * + * Return: Index number in the metadata file of the bitmap block of + * the group specified by @group. + */ +static unsigned long +nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group) +{ + unsigned long desc_offset = + group % nilfs_palloc_groups_per_desc_block(inode); + return nilfs_palloc_desc_blkoff(inode, group) + 1 + + desc_offset * NILFS_MDT(inode)->mi_blocks_per_group; +} + +/** + * nilfs_palloc_group_desc_nfrees - get the number of free entries in a group + * @desc: pointer to descriptor structure for the group + * @lock: spin lock protecting @desc + * + * Return: Number of free entries written in the group descriptor @desc. + */ +static unsigned long +nilfs_palloc_group_desc_nfrees(const struct nilfs_palloc_group_desc *desc, + spinlock_t *lock) +{ + unsigned long nfree; + + spin_lock(lock); + nfree = le32_to_cpu(desc->pg_nfrees); + spin_unlock(lock); + return nfree; +} + +/** + * nilfs_palloc_group_desc_add_entries - adjust count of free entries + * @desc: pointer to descriptor structure for the group + * @lock: spin lock protecting @desc + * @n: delta to be added + * + * Return: Number of free entries after adjusting the group descriptor + * @desc. + */ +static u32 +nilfs_palloc_group_desc_add_entries(struct nilfs_palloc_group_desc *desc, + spinlock_t *lock, u32 n) +{ + u32 nfree; + + spin_lock(lock); + le32_add_cpu(&desc->pg_nfrees, n); + nfree = le32_to_cpu(desc->pg_nfrees); + spin_unlock(lock); + return nfree; +} + +/** + * nilfs_palloc_entry_blkoff - get block offset of an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * + * Return: Index number in the metadata file of the block containing + * the entry specified by @nr. + */ +static unsigned long +nilfs_palloc_entry_blkoff(const struct inode *inode, __u64 nr) +{ + unsigned long group, group_offset; + + group = nilfs_palloc_group(inode, nr, &group_offset); + + return nilfs_palloc_bitmap_blkoff(inode, group) + 1 + + group_offset / NILFS_MDT(inode)->mi_entries_per_block; +} + +/** + * nilfs_palloc_desc_block_init - initialize buffer of a group descriptor block + * @inode: inode of metadata file + * @bh: buffer head of the buffer to be initialized + * @from: kernel address mapped for a chunk of the block + * + * This function does not yet support the case where block size > PAGE_SIZE. + */ +static void nilfs_palloc_desc_block_init(struct inode *inode, + struct buffer_head *bh, void *from) +{ + struct nilfs_palloc_group_desc *desc = from; + unsigned long n = nilfs_palloc_groups_per_desc_block(inode); + __le32 nfrees; + + nfrees = cpu_to_le32(nilfs_palloc_entries_per_group(inode)); + while (n-- > 0) { + desc->pg_nfrees = nfrees; + desc++; + } +} + +static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff, + int create, + void (*init_block)(struct inode *, + struct buffer_head *, + void *), + struct buffer_head **bhp, + struct nilfs_bh_assoc *prev, + spinlock_t *lock) +{ + int ret; + + spin_lock(lock); + if (prev->bh && blkoff == prev->blkoff && + likely(buffer_uptodate(prev->bh))) { + get_bh(prev->bh); + *bhp = prev->bh; + spin_unlock(lock); + return 0; + } + spin_unlock(lock); + + ret = nilfs_mdt_get_block(inode, blkoff, create, init_block, bhp); + if (!ret) { + spin_lock(lock); + /* + * The following code must be safe for change of the + * cache contents during the get block call. + */ + brelse(prev->bh); + get_bh(*bhp); + prev->bh = *bhp; + prev->blkoff = blkoff; + spin_unlock(lock); + } + return ret; +} + +/** + * nilfs_palloc_delete_block - delete a block on the persistent allocator file + * @inode: inode of metadata file using this allocator + * @blkoff: block offset + * @prev: nilfs_bh_assoc struct of the last used buffer + * @lock: spin lock protecting @prev + * + * Return: 0 on success, or one of the following negative error codes on + * failure: + * * %-EIO - I/O error (including metadata corruption). + * * %-ENOENT - Non-existent block. + * * %-ENOMEM - Insufficient memory available. + */ +static int nilfs_palloc_delete_block(struct inode *inode, unsigned long blkoff, + struct nilfs_bh_assoc *prev, + spinlock_t *lock) +{ + spin_lock(lock); + if (prev->bh && blkoff == prev->blkoff) { + brelse(prev->bh); + prev->bh = NULL; + } + spin_unlock(lock); + return nilfs_mdt_delete_block(inode, blkoff); +} + +/** + * nilfs_palloc_get_desc_block - get buffer head of a group descriptor block + * @inode: inode of metadata file using this allocator + * @group: group number + * @create: create flag + * @bhp: pointer to store the resultant buffer head + * + * Return: 0 on success, or a negative error code on failure. + */ +static int nilfs_palloc_get_desc_block(struct inode *inode, + unsigned long group, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_desc_blkoff(inode, group), + create, nilfs_palloc_desc_block_init, + bhp, &cache->prev_desc, &cache->lock); +} + +/** + * nilfs_palloc_get_bitmap_block - get buffer head of a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + * @create: create flag + * @bhp: pointer to store the resultant buffer head + * + * Return: 0 on success, or a negative error code on failure. + */ +static int nilfs_palloc_get_bitmap_block(struct inode *inode, + unsigned long group, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_bitmap_blkoff(inode, group), + create, NULL, bhp, + &cache->prev_bitmap, &cache->lock); +} + +/** + * nilfs_palloc_delete_bitmap_block - delete a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + * + * Return: 0 on success, or a negative error code on failure. + */ +static int nilfs_palloc_delete_bitmap_block(struct inode *inode, + unsigned long group) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_delete_block(inode, + nilfs_palloc_bitmap_blkoff(inode, + group), + &cache->prev_bitmap, &cache->lock); +} + +/** + * nilfs_palloc_get_entry_block - get buffer head of an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @create: create flag + * @bhp: pointer to store the resultant buffer head + * + * Return: 0 on success, or a negative error code on failure. + */ +int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_entry_blkoff(inode, nr), + create, NULL, bhp, + &cache->prev_entry, &cache->lock); +} + +/** + * nilfs_palloc_delete_entry_block - delete an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry + * + * Return: 0 on success, or a negative error code on failure. + */ +static int nilfs_palloc_delete_entry_block(struct inode *inode, __u64 nr) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_delete_block(inode, + nilfs_palloc_entry_blkoff(inode, nr), + &cache->prev_entry, &cache->lock); +} + +/** + * nilfs_palloc_group_desc_offset - calculate the byte offset of a group + * descriptor in the folio containing it + * @inode: inode of metadata file using this allocator + * @group: group number + * @bh: buffer head of the group descriptor block + * + * Return: Byte offset in the folio of the group descriptor for @group. + */ +static size_t nilfs_palloc_group_desc_offset(const struct inode *inode, + unsigned long group, + const struct buffer_head *bh) +{ + return offset_in_folio(bh->b_folio, bh->b_data) + + sizeof(struct nilfs_palloc_group_desc) * + (group % nilfs_palloc_groups_per_desc_block(inode)); +} + +/** + * nilfs_palloc_bitmap_offset - calculate the byte offset of a bitmap block + * in the folio containing it + * @bh: buffer head of the bitmap block + * + * Return: Byte offset in the folio of the bitmap block for @bh. + */ +static size_t nilfs_palloc_bitmap_offset(const struct buffer_head *bh) +{ + return offset_in_folio(bh->b_folio, bh->b_data); +} + +/** + * nilfs_palloc_entry_offset - calculate the byte offset of an entry in the + * folio containing it + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @bh: buffer head of the entry block + * + * Return: Byte offset in the folio of the entry @nr. + */ +size_t nilfs_palloc_entry_offset(const struct inode *inode, __u64 nr, + const struct buffer_head *bh) +{ + unsigned long entry_index_in_group, entry_index_in_block; + + nilfs_palloc_group(inode, nr, &entry_index_in_group); + entry_index_in_block = entry_index_in_group % + NILFS_MDT(inode)->mi_entries_per_block; + + return offset_in_folio(bh->b_folio, bh->b_data) + + entry_index_in_block * NILFS_MDT(inode)->mi_entry_size; +} + +/** + * nilfs_palloc_find_available_slot - find available slot in a group + * @bitmap: bitmap of the group + * @target: offset number of an entry in the group (start point) + * @bsize: size in bits + * @lock: spin lock protecting @bitmap + * @wrap: whether to wrap around + * + * Return: Offset number within the group of the found free entry, or + * %-ENOSPC if not found. + */ +static int nilfs_palloc_find_available_slot(unsigned char *bitmap, + unsigned long target, + unsigned int bsize, + spinlock_t *lock, bool wrap) +{ + int pos, end = bsize; + + if (likely(target < bsize)) { + pos = target; + do { + pos = nilfs_find_next_zero_bit(bitmap, end, pos); + if (pos >= end) + break; + if (!nilfs_set_bit_atomic(lock, pos, bitmap)) + return pos; + } while (++pos < end); + + end = target; + } + if (!wrap) + return -ENOSPC; + + /* wrap around */ + for (pos = 0; pos < end; pos++) { + pos = nilfs_find_next_zero_bit(bitmap, end, pos); + if (pos >= end) + break; + if (!nilfs_set_bit_atomic(lock, pos, bitmap)) + return pos; + } + + return -ENOSPC; +} + +/** + * nilfs_palloc_rest_groups_in_desc_block - get the remaining number of groups + * in a group descriptor block + * @inode: inode of metadata file using this allocator + * @curr: current group number + * @max: maximum number of groups + * + * Return: Number of remaining descriptors (= groups) managed by the descriptor + * block. + */ +static unsigned long +nilfs_palloc_rest_groups_in_desc_block(const struct inode *inode, + unsigned long curr, unsigned long max) +{ + return min_t(unsigned long, + nilfs_palloc_groups_per_desc_block(inode) - + curr % nilfs_palloc_groups_per_desc_block(inode), + max - curr + 1); +} + +/** + * nilfs_palloc_count_desc_blocks - count descriptor blocks number + * @inode: inode of metadata file using this allocator + * @desc_blocks: descriptor blocks number [out] + * + * Return: 0 on success, or a negative error code on failure. + */ +static int nilfs_palloc_count_desc_blocks(struct inode *inode, + unsigned long *desc_blocks) +{ + __u64 blknum; + int ret; + + ret = nilfs_bmap_last_key(NILFS_I(inode)->i_bmap, &blknum); + if (likely(!ret)) + *desc_blocks = DIV_ROUND_UP( + (unsigned long)blknum, + NILFS_MDT(inode)->mi_blocks_per_desc_block); + return ret; +} + +/** + * nilfs_palloc_mdt_file_can_grow - check potential opportunity for + * MDT file growing + * @inode: inode of metadata file using this allocator + * @desc_blocks: known current descriptor blocks count + * + * Return: true if a group can be added in the metadata file, false if not. + */ +static inline bool nilfs_palloc_mdt_file_can_grow(struct inode *inode, + unsigned long desc_blocks) +{ + return (nilfs_palloc_groups_per_desc_block(inode) * desc_blocks) < + nilfs_palloc_groups_count(inode); +} + +/** + * nilfs_palloc_count_max_entries - count max number of entries that can be + * described by descriptor blocks count + * @inode: inode of metadata file using this allocator + * @nused: current number of used entries + * @nmaxp: max number of entries [out] + * + * Return: 0 on success, or one of the following negative error codes on + * failure: + * * %-EIO - I/O error (including metadata corruption). + * * %-ENOMEM - Insufficient memory available. + * * %-ERANGE - Number of entries in use is out of range. + */ +int nilfs_palloc_count_max_entries(struct inode *inode, u64 nused, u64 *nmaxp) +{ + unsigned long desc_blocks = 0; + u64 entries_per_desc_block, nmax; + int err; + + err = nilfs_palloc_count_desc_blocks(inode, &desc_blocks); + if (unlikely(err)) + return err; + + entries_per_desc_block = (u64)nilfs_palloc_entries_per_group(inode) * + nilfs_palloc_groups_per_desc_block(inode); + nmax = entries_per_desc_block * desc_blocks; + + if (nused == nmax && + nilfs_palloc_mdt_file_can_grow(inode, desc_blocks)) + nmax += entries_per_desc_block; + + if (nused > nmax) + return -ERANGE; + + *nmaxp = nmax; + return 0; +} + +/** + * nilfs_palloc_prepare_alloc_entry - prepare to allocate a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + * @wrap: whether to wrap around + * + * Return: 0 on success, or one of the following negative error codes on + * failure: + * * %-EIO - I/O error (including metadata corruption). + * * %-ENOMEM - Insufficient memory available. + * * %-ENOSPC - Entries exhausted (No entries available for allocation). + * * %-EROFS - Read only filesystem + */ +int nilfs_palloc_prepare_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req, bool wrap) +{ + struct buffer_head *desc_bh, *bitmap_bh; + struct nilfs_palloc_group_desc *desc; + unsigned char *bitmap; + size_t doff, boff; + unsigned long group, maxgroup, ngroups; + unsigned long group_offset, maxgroup_offset; + unsigned long n, entries_per_group; + unsigned long i, j; + spinlock_t *lock; + int pos, ret; + + ngroups = nilfs_palloc_groups_count(inode); + maxgroup = ngroups - 1; + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + entries_per_group = nilfs_palloc_entries_per_group(inode); + + for (i = 0; i < ngroups; i += n) { + if (group >= ngroups && wrap) { + /* wrap around */ + group = 0; + maxgroup = nilfs_palloc_group(inode, req->pr_entry_nr, + &maxgroup_offset) - 1; + } + ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh); + if (ret < 0) + return ret; + + doff = nilfs_palloc_group_desc_offset(inode, group, desc_bh); + desc = kmap_local_folio(desc_bh->b_folio, doff); + n = nilfs_palloc_rest_groups_in_desc_block(inode, group, + maxgroup); + for (j = 0; j < n; j++, group++, group_offset = 0) { + lock = nilfs_mdt_bgl_lock(inode, group); + if (nilfs_palloc_group_desc_nfrees(&desc[j], lock) == 0) + continue; + + kunmap_local(desc); + ret = nilfs_palloc_get_bitmap_block(inode, group, 1, + &bitmap_bh); + if (unlikely(ret < 0)) { + brelse(desc_bh); + return ret; + } + + /* + * Re-kmap the folio containing the first (and + * subsequent) group descriptors. + */ + desc = kmap_local_folio(desc_bh->b_folio, doff); + + boff = nilfs_palloc_bitmap_offset(bitmap_bh); + bitmap = kmap_local_folio(bitmap_bh->b_folio, boff); + pos = nilfs_palloc_find_available_slot( + bitmap, group_offset, entries_per_group, lock, + wrap); + /* + * Since the search for a free slot in the second and + * subsequent bitmap blocks always starts from the + * beginning, the wrap flag only has an effect on the + * first search. + */ + kunmap_local(bitmap); + if (pos >= 0) + goto found; + + brelse(bitmap_bh); + } + + kunmap_local(desc); + brelse(desc_bh); + } + + /* no entries left */ + return -ENOSPC; + +found: + /* found a free entry */ + nilfs_palloc_group_desc_add_entries(&desc[j], lock, -1); + req->pr_entry_nr = entries_per_group * group + pos; + kunmap_local(desc); + + req->pr_desc_bh = desc_bh; + req->pr_bitmap_bh = bitmap_bh; + return 0; +} + +/** + * nilfs_palloc_commit_alloc_entry - finish allocation of a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + */ +void nilfs_palloc_commit_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + mark_buffer_dirty(req->pr_bitmap_bh); + mark_buffer_dirty(req->pr_desc_bh); + nilfs_mdt_mark_dirty(inode); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); +} + +/** + * nilfs_palloc_commit_free_entry - finish deallocating a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + */ +void nilfs_palloc_commit_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + unsigned long group, group_offset; + size_t doff, boff; + struct nilfs_palloc_group_desc *desc; + unsigned char *bitmap; + spinlock_t *lock; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + doff = nilfs_palloc_group_desc_offset(inode, group, req->pr_desc_bh); + desc = kmap_local_folio(req->pr_desc_bh->b_folio, doff); + + boff = nilfs_palloc_bitmap_offset(req->pr_bitmap_bh); + bitmap = kmap_local_folio(req->pr_bitmap_bh->b_folio, boff); + lock = nilfs_mdt_bgl_lock(inode, group); + + if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) + nilfs_warn(inode->i_sb, + "%s (ino=%llu): entry number %llu already freed", + __func__, inode->i_ino, + (unsigned long long)req->pr_entry_nr); + else + nilfs_palloc_group_desc_add_entries(desc, lock, 1); + + kunmap_local(bitmap); + kunmap_local(desc); + + mark_buffer_dirty(req->pr_desc_bh); + mark_buffer_dirty(req->pr_bitmap_bh); + nilfs_mdt_mark_dirty(inode); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); +} + +/** + * nilfs_palloc_abort_alloc_entry - cancel allocation of a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + */ +void nilfs_palloc_abort_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct nilfs_palloc_group_desc *desc; + size_t doff, boff; + unsigned char *bitmap; + unsigned long group, group_offset; + spinlock_t *lock; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + doff = nilfs_palloc_group_desc_offset(inode, group, req->pr_desc_bh); + desc = kmap_local_folio(req->pr_desc_bh->b_folio, doff); + + boff = nilfs_palloc_bitmap_offset(req->pr_bitmap_bh); + bitmap = kmap_local_folio(req->pr_bitmap_bh->b_folio, boff); + lock = nilfs_mdt_bgl_lock(inode, group); + + if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) + nilfs_warn(inode->i_sb, + "%s (ino=%llu): entry number %llu already freed", + __func__, inode->i_ino, + (unsigned long long)req->pr_entry_nr); + else + nilfs_palloc_group_desc_add_entries(desc, lock, 1); + + kunmap_local(bitmap); + kunmap_local(desc); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); + + req->pr_entry_nr = 0; + req->pr_bitmap_bh = NULL; + req->pr_desc_bh = NULL; +} + +/** + * nilfs_palloc_prepare_free_entry - prepare to deallocate a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + * + * Return: 0 on success, or a negative error code on failure. + */ +int nilfs_palloc_prepare_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct buffer_head *desc_bh, *bitmap_bh; + unsigned long group, group_offset; + int ret; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh); + if (ret < 0) + return ret; + ret = nilfs_palloc_get_bitmap_block(inode, group, 1, &bitmap_bh); + if (ret < 0) { + brelse(desc_bh); + return ret; + } + + req->pr_desc_bh = desc_bh; + req->pr_bitmap_bh = bitmap_bh; + return 0; +} + +/** + * nilfs_palloc_abort_free_entry - cancel deallocating a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + */ +void nilfs_palloc_abort_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); + + req->pr_entry_nr = 0; + req->pr_bitmap_bh = NULL; + req->pr_desc_bh = NULL; +} + +/** + * nilfs_palloc_freev - deallocate a set of persistent objects + * @inode: inode of metadata file using this allocator + * @entry_nrs: array of entry numbers to be deallocated + * @nitems: number of entries stored in @entry_nrs + * + * Return: 0 on success, or a negative error code on failure. + */ +int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) +{ + struct buffer_head *desc_bh, *bitmap_bh; + struct nilfs_palloc_group_desc *desc; + unsigned char *bitmap; + size_t doff, boff; + unsigned long group, group_offset; + __u64 group_min_nr, last_nrs[8]; + const unsigned long epg = nilfs_palloc_entries_per_group(inode); + const unsigned int epb = NILFS_MDT(inode)->mi_entries_per_block; + unsigned int entry_start, end, pos; + spinlock_t *lock; + int i, j, k, ret; + u32 nfree; + + for (i = 0; i < nitems; i = j) { + int change_group = false; + int nempties = 0, n = 0; + + group = nilfs_palloc_group(inode, entry_nrs[i], &group_offset); + ret = nilfs_palloc_get_desc_block(inode, group, 0, &desc_bh); + if (ret < 0) + return ret; + ret = nilfs_palloc_get_bitmap_block(inode, group, 0, + &bitmap_bh); + if (ret < 0) { + brelse(desc_bh); + return ret; + } + + /* Get the first entry number of the group */ + group_min_nr = (__u64)group * epg; + + boff = nilfs_palloc_bitmap_offset(bitmap_bh); + bitmap = kmap_local_folio(bitmap_bh->b_folio, boff); + lock = nilfs_mdt_bgl_lock(inode, group); + + j = i; + entry_start = rounddown(group_offset, epb); + do { + if (!nilfs_clear_bit_atomic(lock, group_offset, + bitmap)) { + nilfs_warn(inode->i_sb, + "%s (ino=%llu): entry number %llu already freed", + __func__, inode->i_ino, + (unsigned long long)entry_nrs[j]); + } else { + n++; + } + + j++; + if (j >= nitems || entry_nrs[j] < group_min_nr || + entry_nrs[j] >= group_min_nr + epg) { + change_group = true; + } else { + group_offset = entry_nrs[j] - group_min_nr; + if (group_offset >= entry_start && + group_offset < entry_start + epb) { + /* This entry is in the same block */ + continue; + } + } + + /* Test if the entry block is empty or not */ + end = entry_start + epb; + pos = nilfs_find_next_bit(bitmap, end, entry_start); + if (pos >= end) { + last_nrs[nempties++] = entry_nrs[j - 1]; + if (nempties >= ARRAY_SIZE(last_nrs)) + break; + } + + if (change_group) + break; + + /* Go on to the next entry block */ + entry_start = rounddown(group_offset, epb); + } while (true); + + kunmap_local(bitmap); + mark_buffer_dirty(bitmap_bh); + brelse(bitmap_bh); + + for (k = 0; k < nempties; k++) { + ret = nilfs_palloc_delete_entry_block(inode, + last_nrs[k]); + if (ret && ret != -ENOENT) + nilfs_warn(inode->i_sb, + "error %d deleting block that object (entry=%llu, ino=%llu) belongs to", + ret, (unsigned long long)last_nrs[k], + inode->i_ino); + } + + doff = nilfs_palloc_group_desc_offset(inode, group, desc_bh); + desc = kmap_local_folio(desc_bh->b_folio, doff); + nfree = nilfs_palloc_group_desc_add_entries(desc, lock, n); + kunmap_local(desc); + mark_buffer_dirty(desc_bh); + nilfs_mdt_mark_dirty(inode); + brelse(desc_bh); + + if (nfree == nilfs_palloc_entries_per_group(inode)) { + ret = nilfs_palloc_delete_bitmap_block(inode, group); + if (ret && ret != -ENOENT) + nilfs_warn(inode->i_sb, + "error %d deleting bitmap block of group=%lu, ino=%llu", + ret, group, inode->i_ino); + } + } + return 0; +} + +void nilfs_palloc_setup_cache(struct inode *inode, + struct nilfs_palloc_cache *cache) +{ + NILFS_MDT(inode)->mi_palloc_cache = cache; + spin_lock_init(&cache->lock); +} + +void nilfs_palloc_clear_cache(struct inode *inode) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + spin_lock(&cache->lock); + brelse(cache->prev_desc.bh); + brelse(cache->prev_bitmap.bh); + brelse(cache->prev_entry.bh); + cache->prev_desc.bh = NULL; + cache->prev_bitmap.bh = NULL; + cache->prev_entry.bh = NULL; + spin_unlock(&cache->lock); +} + +void nilfs_palloc_destroy_cache(struct inode *inode) +{ + nilfs_palloc_clear_cache(inode); + NILFS_MDT(inode)->mi_palloc_cache = NULL; +} -- cgit v1.3.1