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23 October 2021, 00:29:24 UTC
Revision 4f258a46346c03fa0bbb6199ffaf4e1f9f599660 authored by Martin K. Petersen on 23 June 2015, 16:13:59 UTC, committed by James Bottomley on 12 August 2015, 18:54:37 UTC 
sd: Fix maximum I/O size for BLOCK_PC requests
 
Commit bcdb247c6b6a ("sd: Limit transfer length") clamped the maximum
size of an I/O request to the MAXIMUM TRANSFER LENGTH field in the BLOCK
LIMITS VPD. This had the unfortunate effect of also limiting the maximum
size of non-filesystem requests sent to the device through sg/bsg.

Avoid using blk_queue_max_hw_sectors() and set the max_sectors queue
limit directly.

Also update the comment in blk_limits_max_hw_sectors() to clarify that
max_hw_sectors defines the limit for the I/O controller only.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Brian King <brking@linux.vnet.ibm.com>
Tested-by: Brian King <brking@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: James Bottomley <JBottomley@Odin.com>
1 parent 8f2777f
Raw File
Tip revision: 4f258a46346c03fa0bbb6199ffaf4e1f9f599660 authored by Martin K. Petersen on 23 June 2015, 16:13:59 UTC
sd: Fix maximum I/O size for BLOCK_PC requests
Tip revision: 4f258a4
Kbuild 
#
# Kbuild for top-level directory of the kernel
# This file takes care of the following:
# 1) Generate bounds.h
# 2) Generate timeconst.h
# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
# 4) Check for missing system calls

# Default sed regexp - multiline due to syntax constraints
define sed-y
	"/^->/{s:->#\(.*\):/* \1 */:; \
	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
	s:->::; p;}"
endef

# Use filechk to avoid rebuilds when a header changes, but the resulting file
# does not
define filechk_offsets
	(set -e; \
	 echo "#ifndef $2"; \
	 echo "#define $2"; \
	 echo "/*"; \
	 echo " * DO NOT MODIFY."; \
	 echo " *"; \
	 echo " * This file was generated by Kbuild"; \
	 echo " */"; \
	 echo ""; \
	 sed -ne $(sed-y); \
	 echo ""; \
	 echo "#endif" )
endef

#####
# 1) Generate bounds.h

bounds-file := include/generated/bounds.h

always  := $(bounds-file)
targets := kernel/bounds.s

# We use internal kbuild rules to avoid the "is up to date" message from make
kernel/bounds.s: kernel/bounds.c FORCE
	$(Q)mkdir -p $(dir $@)
	$(call if_changed_dep,cc_s_c)

$(obj)/$(bounds-file): kernel/bounds.s FORCE
	$(call filechk,offsets,__LINUX_BOUNDS_H__)

#####
# 2) Generate timeconst.h

timeconst-file := include/generated/timeconst.h

targets += $(timeconst-file)

quiet_cmd_gentimeconst = GEN     $@
define cmd_gentimeconst
	(echo $(CONFIG_HZ) | bc -q $< ) > $@
endef
define filechk_gentimeconst
	(echo $(CONFIG_HZ) | bc -q $< )
endef

$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
	$(call filechk,gentimeconst)

#####
# 3) Generate asm-offsets.h
#

offsets-file := include/generated/asm-offsets.h

always  += $(offsets-file)
targets += arch/$(SRCARCH)/kernel/asm-offsets.s

# We use internal kbuild rules to avoid the "is up to date" message from make
arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
                                      $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
	$(Q)mkdir -p $(dir $@)
	$(call if_changed_dep,cc_s_c)

$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
	$(call filechk,offsets,__ASM_OFFSETS_H__)

#####
# 4) Check for missing system calls
#

always += missing-syscalls
targets += missing-syscalls

quiet_cmd_syscalls = CALL    $<
      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)

missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
	$(call cmd,syscalls)

# Keep these three files during make clean
no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
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