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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /fs/minix/itree_common.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'fs/minix/itree_common.c')
| -rw-r--r-- | fs/minix/itree_common.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/fs/minix/itree_common.c b/fs/minix/itree_common.c new file mode 100644 index 000000000..c3cd2c75a --- /dev/null +++ b/fs/minix/itree_common.c @@ -0,0 +1,374 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Generic part */ + +typedef struct { + block_t *p; + block_t key; + struct buffer_head *bh; +} Indirect; + +static DEFINE_RWLOCK(pointers_lock); + +static inline void add_chain(Indirect *p, struct buffer_head *bh, block_t *v) +{ + p->key = *(p->p = v); + p->bh = bh; +} + +static inline int verify_chain(Indirect *from, Indirect *to) +{ + while (from <= to && from->key == *from->p) + from++; + return (from > to); +} + +static inline block_t *block_end(struct buffer_head *bh) +{ + return (block_t *)((char*)bh->b_data + bh->b_size); +} + +static inline Indirect *get_branch(struct inode *inode, + int depth, + int *offsets, + Indirect chain[DEPTH], + int *err) +{ + struct super_block *sb = inode->i_sb; + Indirect *p = chain; + struct buffer_head *bh; + + *err = 0; + /* i_data is not going away, no lock needed */ + add_chain (chain, NULL, i_data(inode) + *offsets); + if (!p->key) + goto no_block; + while (--depth) { + bh = sb_bread(sb, block_to_cpu(p->key)); + if (!bh) + goto failure; + read_lock(&pointers_lock); + if (!verify_chain(chain, p)) + goto changed; + add_chain(++p, bh, (block_t *)bh->b_data + *++offsets); + read_unlock(&pointers_lock); + if (!p->key) + goto no_block; + } + return NULL; + +changed: + read_unlock(&pointers_lock); + brelse(bh); + *err = -EAGAIN; + goto no_block; +failure: + *err = -EIO; +no_block: + return p; +} + +static int alloc_branch(struct inode *inode, + int num, + int *offsets, + Indirect *branch) +{ + int n = 0; + int i; + int parent = minix_new_block(inode); + int err = -ENOSPC; + + branch[0].key = cpu_to_block(parent); + if (parent) for (n = 1; n < num; n++) { + struct buffer_head *bh; + /* Allocate the next block */ + int nr = minix_new_block(inode); + if (!nr) + break; + branch[n].key = cpu_to_block(nr); + bh = sb_getblk(inode->i_sb, parent); + if (!bh) { + minix_free_block(inode, nr); + err = -ENOMEM; + break; + } + lock_buffer(bh); + memset(bh->b_data, 0, bh->b_size); + branch[n].bh = bh; + branch[n].p = (block_t*) bh->b_data + offsets[n]; + *branch[n].p = branch[n].key; + set_buffer_uptodate(bh); + unlock_buffer(bh); + mmb_mark_buffer_dirty(bh, &minix_i(inode)->i_metadata_bhs); + parent = nr; + } + if (n == num) + return 0; + + /* Allocation failed, free what we already allocated */ + for (i = 1; i < n; i++) + bforget(branch[i].bh); + for (i = 0; i < n; i++) + minix_free_block(inode, block_to_cpu(branch[i].key)); + return err; +} + +static inline int splice_branch(struct inode *inode, + Indirect chain[DEPTH], + Indirect *where, + int num) +{ + int i; + + write_lock(&pointers_lock); + + /* Verify that place we are splicing to is still there and vacant */ + if (!verify_chain(chain, where-1) || *where->p) + goto changed; + + *where->p = where->key; + + write_unlock(&pointers_lock); + + /* We are done with atomic stuff, now do the rest of housekeeping */ + + inode_set_ctime_current(inode); + + /* had we spliced it onto indirect block? */ + if (where->bh) + mmb_mark_buffer_dirty(where->bh, + &minix_i(inode)->i_metadata_bhs); + + mark_inode_dirty(inode); + return 0; + +changed: + write_unlock(&pointers_lock); + for (i = 1; i < num; i++) + bforget(where[i].bh); + for (i = 0; i < num; i++) + minix_free_block(inode, block_to_cpu(where[i].key)); + return -EAGAIN; +} + +static int get_block(struct inode * inode, sector_t block, + struct buffer_head *bh, int create) +{ + int err = -EIO; + int offsets[DEPTH]; + Indirect chain[DEPTH]; + Indirect *partial; + int left; + int depth = block_to_path(inode, block, offsets); + + if (depth == 0) + goto out; + +reread: + partial = get_branch(inode, depth, offsets, chain, &err); + + /* Simplest case - block found, no allocation needed */ + if (!partial) { +got_it: + map_bh(bh, inode->i_sb, block_to_cpu(chain[depth-1].key)); + /* Clean up and exit */ + partial = chain+depth-1; /* the whole chain */ + goto cleanup; + } + + /* Next simple case - plain lookup or failed read of indirect block */ + if (!create || err == -EIO) { +cleanup: + while (partial > chain) { + brelse(partial->bh); + partial--; + } +out: + return err; + } + + /* + * Indirect block might be removed by truncate while we were + * reading it. Handling of that case (forget what we've got and + * reread) is taken out of the main path. + */ + if (err == -EAGAIN) + goto changed; + + left = (chain + depth) - partial; + err = alloc_branch(inode, left, offsets+(partial-chain), partial); + if (err) + goto cleanup; + + if (splice_branch(inode, chain, partial, left) < 0) + goto changed; + + set_buffer_new(bh); + goto got_it; + +changed: + while (partial > chain) { + brelse(partial->bh); + partial--; + } + goto reread; +} + +static inline int all_zeroes(block_t *p, block_t *q) +{ + while (p < q) + if (*p++) + return 0; + return 1; +} + +static Indirect *find_shared(struct inode *inode, + int depth, + int offsets[DEPTH], + Indirect chain[DEPTH], + block_t *top) +{ + Indirect *partial, *p; + int k, err; + + *top = 0; + for (k = depth; k > 1 && !offsets[k-1]; k--) + ; + partial = get_branch(inode, k, offsets, chain, &err); + + write_lock(&pointers_lock); + if (!partial) + partial = chain + k-1; + if (!partial->key && *partial->p) { + write_unlock(&pointers_lock); + goto no_top; + } + for (p=partial;p>chain && all_zeroes((block_t*)p->bh->b_data,p->p);p--) + ; + if (p == chain + k - 1 && p > chain) { + p->p--; + } else { + *top = *p->p; + *p->p = 0; + } + write_unlock(&pointers_lock); + + while(partial > p) + { + brelse(partial->bh); + partial--; + } +no_top: + return partial; +} + +static inline void free_data(struct inode *inode, block_t *p, block_t *q) +{ + unsigned long nr; + + for ( ; p < q ; p++) { + nr = block_to_cpu(*p); + if (nr) { + *p = 0; + minix_free_block(inode, nr); + } + } +} + +static void free_branches(struct inode *inode, block_t *p, block_t *q, int depth) +{ + struct buffer_head * bh; + unsigned long nr; + + if (depth--) { + for ( ; p < q ; p++) { + nr = block_to_cpu(*p); + if (!nr) + continue; + *p = 0; + bh = sb_bread(inode->i_sb, nr); + if (!bh) + continue; + free_branches(inode, (block_t*)bh->b_data, + block_end(bh), depth); + bforget(bh); + minix_free_block(inode, nr); + mark_inode_dirty(inode); + } + } else + free_data(inode, p, q); +} + +static inline void truncate (struct inode * inode) +{ + struct super_block *sb = inode->i_sb; + block_t *idata = i_data(inode); + int offsets[DEPTH]; + Indirect chain[DEPTH]; + Indirect *partial; + block_t nr = 0; + int n; + int first_whole; + long iblock; + + iblock = (inode->i_size + sb->s_blocksize -1) >> sb->s_blocksize_bits; + block_truncate_page(inode->i_mapping, inode->i_size, get_block); + + n = block_to_path(inode, iblock, offsets); + if (!n) + return; + + if (n == 1) { + free_data(inode, idata+offsets[0], idata + DIRECT); + first_whole = 0; + goto do_indirects; + } + + first_whole = offsets[0] + 1 - DIRECT; + partial = find_shared(inode, n, offsets, chain, &nr); + if (nr) { + if (partial == chain) + mark_inode_dirty(inode); + else + mmb_mark_buffer_dirty(partial->bh, + &minix_i(inode)->i_metadata_bhs); + free_branches(inode, &nr, &nr+1, (chain+n-1) - partial); + } + /* Clear the ends of indirect blocks on the shared branch */ + while (partial > chain) { + free_branches(inode, partial->p + 1, block_end(partial->bh), + (chain+n-1) - partial); + mmb_mark_buffer_dirty(partial->bh, + &minix_i(inode)->i_metadata_bhs); + brelse (partial->bh); + partial--; + } +do_indirects: + /* Kill the remaining (whole) subtrees */ + while (first_whole < DEPTH-1) { + nr = idata[DIRECT+first_whole]; + if (nr) { + idata[DIRECT+first_whole] = 0; + mark_inode_dirty(inode); + free_branches(inode, &nr, &nr+1, first_whole+1); + } + first_whole++; + } + inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); + mark_inode_dirty(inode); +} + +static inline unsigned nblocks(loff_t size, struct super_block *sb) +{ + int k = sb->s_blocksize_bits - 10; + unsigned blocks, res, direct = DIRECT, i = DEPTH; + blocks = (size + sb->s_blocksize - 1) >> (BLOCK_SIZE_BITS + k); + res = blocks; + while (--i && blocks > direct) { + blocks -= direct; + blocks += sb->s_blocksize/sizeof(block_t) - 1; + blocks /= sb->s_blocksize/sizeof(block_t); + res += blocks; + direct = 1; + } + return res; +} |
