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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /fs/hfs/bitmap.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'fs/hfs/bitmap.c')
-rw-r--r--fs/hfs/bitmap.c243
1 files changed, 243 insertions, 0 deletions
diff --git a/fs/hfs/bitmap.c b/fs/hfs/bitmap.c
new file mode 100644
index 000000000..5e84833a4
--- /dev/null
+++ b/fs/hfs/bitmap.c
@@ -0,0 +1,243 @@
+/*
+ * linux/fs/hfs/bitmap.c
+ *
+ * Copyright (C) 1996-1997 Paul H. Hargrove
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ * This file may be distributed under the terms of the GNU General Public License.
+ *
+ * Based on GPLed code Copyright (C) 1995 Michael Dreher
+ *
+ * This file contains the code to modify the volume bitmap:
+ * search/set/clear bits.
+ */
+
+#include "hfs_fs.h"
+
+/*
+ * hfs_find_zero_bit()
+ *
+ * Description:
+ * Given a block of memory, its length in bits, and a starting bit number,
+ * determine the number of the first zero bits (in left-to-right ordering)
+ * in that range.
+ *
+ * Returns >= 'size' if no zero bits are found in the range.
+ *
+ * Accesses memory in 32-bit aligned chunks of 32-bits and thus
+ * may read beyond the 'size'th bit.
+ */
+static u32 hfs_find_set_zero_bits(__be32 *bitmap, u32 size, u32 offset, u32 *max)
+{
+ __be32 *curr, *end;
+ u32 mask, start, len, n;
+ __be32 val;
+ int i;
+
+ len = *max;
+ if (!len)
+ return size;
+
+ curr = bitmap + (offset / 32);
+ end = bitmap + ((size + 31) / 32);
+
+ /* scan the first partial u32 for zero bits */
+ val = *curr;
+ if (~val) {
+ n = be32_to_cpu(val);
+ i = offset % 32;
+ mask = (1U << 31) >> i;
+ for (; i < 32; mask >>= 1, i++) {
+ if (!(n & mask))
+ goto found;
+ }
+ }
+
+ /* scan complete u32s for the first zero bit */
+ 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;
+ }
+ }
+ }
+ return size;
+
+found:
+ start = (curr - bitmap) * 32 + i;
+ if (start >= size)
+ return start;
+ /* 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) {
+ n = be32_to_cpu(*curr);
+ if (len < 32)
+ break;
+ if (n) {
+ len = 32;
+ break;
+ }
+ *curr++ = cpu_to_be32(0xffffffff);
+ len -= 32;
+ }
+ /* 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);
+ *max = (curr - bitmap) * 32 + i - start;
+ return start;
+}
+
+/*
+ * hfs_vbm_search_free()
+ *
+ * Description:
+ * Search for 'num_bits' consecutive cleared bits in the bitmap blocks of
+ * the hfs MDB. 'mdb' had better be locked or the returned range
+ * may be no longer free, when this functions returns!
+ * XXX Currently the search starts from bit 0, but it should start with
+ * the bit number stored in 's_alloc_ptr' of the MDB.
+ * Input Variable(s):
+ * struct hfs_mdb *mdb: Pointer to the hfs MDB
+ * u16 *num_bits: Pointer to the number of cleared bits
+ * to search for
+ * Output Variable(s):
+ * u16 *num_bits: The number of consecutive clear bits of the
+ * returned range. If the bitmap is fragmented, this will be less than
+ * requested and it will be zero, when the disk is full.
+ * Returns:
+ * The number of the first bit of the range of cleared bits which has been
+ * found. When 'num_bits' is zero, this is invalid!
+ * Preconditions:
+ * 'mdb' points to a "valid" (struct hfs_mdb).
+ * 'num_bits' points to a variable of type (u16), which contains
+ * the number of cleared bits to find.
+ * Postconditions:
+ * 'num_bits' is set to the length of the found sequence.
+ */
+u32 hfs_vbm_search_free(struct super_block *sb, u32 goal, u32 *num_bits)
+{
+ void *bitmap;
+ u32 pos;
+
+ /* make sure we have actual work to perform */
+ if (!*num_bits)
+ return 0;
+
+ mutex_lock(&HFS_SB(sb)->bitmap_lock);
+ bitmap = HFS_SB(sb)->bitmap;
+
+ pos = hfs_find_set_zero_bits(bitmap, HFS_SB(sb)->fs_ablocks, goal, num_bits);
+ if (pos >= HFS_SB(sb)->fs_ablocks) {
+ if (goal)
+ pos = hfs_find_set_zero_bits(bitmap, goal, 0, num_bits);
+ if (pos >= HFS_SB(sb)->fs_ablocks) {
+ *num_bits = pos = 0;
+ goto out;
+ }
+ }
+
+ hfs_dbg("pos %u, num_bits %u\n", pos, *num_bits);
+ HFS_SB(sb)->free_ablocks -= *num_bits;
+ hfs_bitmap_dirty(sb);
+out:
+ mutex_unlock(&HFS_SB(sb)->bitmap_lock);
+ return pos;
+}
+
+
+/*
+ * hfs_clear_vbm_bits()
+ *
+ * Description:
+ * Clear the requested bits in the volume bitmap of the hfs filesystem
+ * Input Variable(s):
+ * struct hfs_mdb *mdb: Pointer to the hfs MDB
+ * u16 start: The offset of the first bit
+ * u16 count: The number of bits
+ * Output Variable(s):
+ * None
+ * Returns:
+ * 0: no error
+ * -1: One of the bits was already clear. This is a strange
+ * error and when it happens, the filesystem must be repaired!
+ * -2: One or more of the bits are out of range of the bitmap.
+ * Preconditions:
+ * 'mdb' points to a "valid" (struct hfs_mdb).
+ * Postconditions:
+ * Starting with bit number 'start', 'count' bits in the volume bitmap
+ * are cleared. The affected bitmap blocks are marked "dirty", the free
+ * block count of the MDB is updated and the MDB is marked dirty.
+ */
+int hfs_clear_vbm_bits(struct super_block *sb, u16 start, u16 count)
+{
+ __be32 *curr;
+ u32 mask;
+ int i, len;
+
+ /* is there any actual work to be done? */
+ if (!count)
+ return 0;
+
+ hfs_dbg("start %u, count %u\n", start, count);
+ /* are all of the bits in range? */
+ if ((start + count) > HFS_SB(sb)->fs_ablocks)
+ return -2;
+
+ mutex_lock(&HFS_SB(sb)->bitmap_lock);
+ /* bitmap is always on a 32-bit boundary */
+ curr = HFS_SB(sb)->bitmap + (start / 32);
+ len = count;
+
+ /* do any partial u32 at the start */
+ i = start % 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 (count >= 32) {
+ *curr++ = 0;
+ count -= 32;
+ }
+ /* do any partial u32 at end */
+ if (count) {
+ mask = 0xffffffffU >> count;
+ *curr &= cpu_to_be32(mask);
+ }
+out:
+ HFS_SB(sb)->free_ablocks += len;
+ mutex_unlock(&HFS_SB(sb)->bitmap_lock);
+ hfs_bitmap_dirty(sb);
+
+ return 0;
+}