/linux/include/asm-generic/ |
H A D | access_ok.h | 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/csky/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/nios2/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/sparc/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
H A D | uaccess_32.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
H A D | uaccess_64.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/hexagon/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/m68k/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/arc/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/openrisc/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/sh/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/alpha/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/xtensa/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/riscv/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/mips/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/microblaze/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/parisc/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/arm/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/powerpc/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/arm64/include/asm/ |
H A D | uaccess.h | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
/linux/arch/sparc/ |
H A D | Kconfig | diff 12700c17fc286149324f92d6d380bc48e43f253d Tue Feb 15 17:55:04 CET 2022 Arnd Bergmann <arnd@arndb.de> uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything.
Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections.
For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong.
Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this.
Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch.
Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|