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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/hfsplus/bitmap.c
downloadlinux-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/hfsplus/bitmap.c')
-rw-r--r--fs/hfsplus/bitmap.c246
1 files changed, 246 insertions, 0 deletions
diff --git a/fs/hfsplus/bitmap.c b/fs/hfsplus/bitmap.c
new file mode 100644
index 000000000..1b3af8c87
--- /dev/null
+++ b/fs/hfsplus/bitmap.c
@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/hfsplus/bitmap.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Handling of allocation file
+ */
+
+#include <linux/pagemap.h>
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+#define PAGE_CACHE_BITS (PAGE_SIZE * 8)
+
+int hfsplus_block_allocate(struct super_block *sb, u32 size,
+ u32 offset, u32 *max)
+{
+ struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+ struct page *page;
+ struct address_space *mapping;
+ __be32 *pptr, *curr, *end;
+ u32 mask, start, len, n;
+ __be32 val;
+ int i;
+
+ len = *max;
+ if (!len)
+ return size;
+
+ hfs_dbg("size %u, offset %u, len %u\n", size, offset, len);
+ mutex_lock(&sbi->alloc_mutex);
+ mapping = sbi->alloc_file->i_mapping;
+ page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS, NULL);
+ if (IS_ERR(page)) {
+ start = size;
+ goto out;
+ }
+ pptr = kmap_local_page(page);
+ curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
+ i = offset % 32;
+ offset &= ~(PAGE_CACHE_BITS - 1);
+ if ((size ^ offset) / PAGE_CACHE_BITS)
+ end = pptr + PAGE_CACHE_BITS / 32;
+ else
+ end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
+
+ /* scan the first partial u32 for zero bits */
+ val = *curr;
+ if (~val) {
+ n = be32_to_cpu(val);
+ mask = (1U << 31) >> i;
+ for (; i < 32; mask >>= 1, i++) {
+ if (!(n & mask))
+ goto found;
+ }
+ }
+ curr++;
+
+ /* scan complete u32s for the first zero bit */
+ while (1) {
+ while (curr < end) {
+ val = *curr;
+ if (~val) {
+ n = be32_to_cpu(val);
+ mask = 1 << 31;
+ for (i = 0; i < 32; mask >>= 1, i++) {
+ if (!(n & mask))
+ goto found;
+ }
+ }
+ curr++;
+ }
+ kunmap_local(pptr);
+ offset += PAGE_CACHE_BITS;
+ if (offset >= size)
+ break;
+ page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
+ NULL);
+ if (IS_ERR(page)) {
+ start = size;
+ goto out;
+ }
+ curr = pptr = kmap_local_page(page);
+ if ((size ^ offset) / PAGE_CACHE_BITS)
+ end = pptr + PAGE_CACHE_BITS / 32;
+ else
+ end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
+ }
+ hfs_dbg("bitmap full\n");
+ start = size;
+ goto out;
+
+found:
+ start = offset + (curr - pptr) * 32 + i;
+ if (start >= size) {
+ hfs_dbg("bitmap full\n");
+ goto out;
+ }
+ /* do any partial u32 at the start */
+ len = min(size - start, len);
+ while (1) {
+ n |= mask;
+ if (++i >= 32)
+ break;
+ mask >>= 1;
+ if (!--len || n & mask)
+ goto done;
+ }
+ if (!--len)
+ goto done;
+ *curr++ = cpu_to_be32(n);
+ /* do full u32s */
+ while (1) {
+ while (curr < end) {
+ n = be32_to_cpu(*curr);
+ if (len < 32)
+ goto last;
+ if (n) {
+ len = 32;
+ goto last;
+ }
+ *curr++ = cpu_to_be32(0xffffffff);
+ len -= 32;
+ }
+ set_page_dirty(page);
+ kunmap_local(pptr);
+ offset += PAGE_CACHE_BITS;
+ page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
+ NULL);
+ if (IS_ERR(page)) {
+ start = size;
+ goto out;
+ }
+ pptr = kmap_local_page(page);
+ curr = pptr;
+ end = pptr + PAGE_CACHE_BITS / 32;
+ }
+last:
+ /* do any partial u32 at end */
+ mask = 1U << 31;
+ for (i = 0; i < len; i++) {
+ if (n & mask)
+ break;
+ n |= mask;
+ mask >>= 1;
+ }
+done:
+ *curr = cpu_to_be32(n);
+ set_page_dirty(page);
+ kunmap_local(pptr);
+ *max = offset + (curr - pptr) * 32 + i - start;
+ sbi->free_blocks -= *max;
+ hfsplus_mark_mdb_dirty(sb);
+ hfs_dbg("start %u, max %u\n", start, *max);
+out:
+ mutex_unlock(&sbi->alloc_mutex);
+ return start;
+}
+
+int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count)
+{
+ struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+ struct page *page;
+ struct address_space *mapping;
+ __be32 *pptr, *curr, *end;
+ u32 mask, len, pnr;
+ int i;
+
+ /* is there any actual work to be done? */
+ if (!count)
+ return 0;
+
+ hfs_dbg("offset %u, count %u\n", offset, count);
+ /* are all of the bits in range? */
+ if ((offset + count) > sbi->total_blocks)
+ return -ENOENT;
+
+ mutex_lock(&sbi->alloc_mutex);
+ mapping = sbi->alloc_file->i_mapping;
+ pnr = offset / PAGE_CACHE_BITS;
+ page = read_mapping_page(mapping, pnr, NULL);
+ if (IS_ERR(page))
+ goto kaboom;
+ pptr = kmap_local_page(page);
+ curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
+ end = pptr + PAGE_CACHE_BITS / 32;
+ len = count;
+
+ /* do any partial u32 at the start */
+ i = offset % 32;
+ if (i) {
+ int j = 32 - i;
+ mask = 0xffffffffU << j;
+ if (j > count) {
+ mask |= 0xffffffffU >> (i + count);
+ *curr++ &= cpu_to_be32(mask);
+ goto out;
+ }
+ *curr++ &= cpu_to_be32(mask);
+ count -= j;
+ }
+
+ /* do full u32s */
+ while (1) {
+ while (curr < end) {
+ if (count < 32)
+ goto done;
+ *curr++ = 0;
+ count -= 32;
+ }
+ if (!count)
+ break;
+ set_page_dirty(page);
+ kunmap_local(pptr);
+ page = read_mapping_page(mapping, ++pnr, NULL);
+ if (IS_ERR(page))
+ goto kaboom;
+ pptr = kmap_local_page(page);
+ curr = pptr;
+ end = pptr + PAGE_CACHE_BITS / 32;
+ }
+done:
+ /* do any partial u32 at end */
+ if (count) {
+ mask = 0xffffffffU >> count;
+ *curr &= cpu_to_be32(mask);
+ }
+out:
+ set_page_dirty(page);
+ kunmap_local(pptr);
+ sbi->free_blocks += len;
+ hfsplus_mark_mdb_dirty(sb);
+ mutex_unlock(&sbi->alloc_mutex);
+
+ return 0;
+
+kaboom:
+ pr_crit("unable to mark blocks free: error %ld\n", PTR_ERR(page));
+ mutex_unlock(&sbi->alloc_mutex);
+
+ return -EIO;
+}