summaryrefslogtreecommitdiffstats
path: root/Documentation/admin-guide/device-mapper/dm-ebs.rst
diff options
context:
space:
mode:
authorSalah Triki <salah.triki@gmail.com>2026-09-17 14:00:52 +0100
committerJonathan Cameron <jonathan.cameron@oss.qualcomm.com>2026-09-30 18:59:55 +0100
commite8dd273d199f5bbe295a8e3d8b777c5505b6b2e1 (patch)
tree767c7e109d3e6b9ec6549e99dfec9085d01318ad /Documentation/admin-guide/device-mapper/dm-ebs.rst
downloadlinux-stable-e8dd273d199f5bbe295a8e3d8b777c5505b6b2e1.tar.gz
linux-stable-e8dd273d199f5bbe295a8e3d8b777c5505b6b2e1.zip
iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted
isl29501_register_write() was returning a u32 instead of an int. Since the function returns negative error codes (such as -ERANGE or return values from i2c_smbus_write_byte_data()), returning an unsigned integer type prevents callers from correctly checking for negative error conditions. Fix this by changing the function return type from u32 to int. This was found through manual code review. Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.") Signed-off-by: Salah Triki <salah.triki@gmail.com> Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Diffstat (limited to 'Documentation/admin-guide/device-mapper/dm-ebs.rst')
-rw-r--r--Documentation/admin-guide/device-mapper/dm-ebs.rst51
1 files changed, 51 insertions, 0 deletions
diff --git a/Documentation/admin-guide/device-mapper/dm-ebs.rst b/Documentation/admin-guide/device-mapper/dm-ebs.rst
new file mode 100644
index 000000000..c09f66db5
--- /dev/null
+++ b/Documentation/admin-guide/device-mapper/dm-ebs.rst
@@ -0,0 +1,51 @@
+======
+dm-ebs
+======
+
+
+This target is similar to the linear target except that it emulates
+a smaller logical block size on a device with a larger logical block
+size. Its main purpose is to provide emulation of 512 byte sectors on
+devices that do not provide this emulation (i.e. 4K native disks).
+
+Supported emulated logical block sizes 512, 1024, 2048 and 4096.
+
+Underlying block size can be set to > 4K to test buffering larger units.
+
+
+Table parameters
+----------------
+ <dev path> <offset> <emulated sectors> [<underlying sectors>]
+
+Mandatory parameters:
+
+ <dev path>:
+ Full pathname to the underlying block-device,
+ or a "major:minor" device-number.
+ <offset>:
+ Starting sector within the device;
+ has to be a multiple of <emulated sectors>.
+ <emulated sectors>:
+ Number of sectors defining the logical block size to be emulated;
+ 1, 2, 4, 8 sectors of 512 bytes supported.
+
+Optional parameter:
+
+ <underlying sectors>:
+ Number of sectors defining the logical block size of <dev path>.
+ 2^N supported, e.g. 8 = emulate 8 sectors of 512 bytes = 4KiB.
+ If not provided, the logical block size of <dev path> will be used.
+
+
+Examples:
+
+Emulate 1 sector = 512 bytes logical block size on /dev/sda starting at
+offset 1024 sectors with underlying devices block size automatically set:
+
+ebs /dev/sda 1024 1
+
+Emulate 2 sector = 1KiB logical block size on /dev/sda starting at
+offset 128 sectors, enforce 2KiB underlying device block size.
+This presumes 2KiB logical blocksize on /dev/sda or less to work:
+
+ebs /dev/sda 128 2 4