linux_dsm_epyc7002/arch/alpha/kernel
Nicolin Chen 1e9d90dbed dma-mapping: introduce dma_get_seg_boundary_nr_pages()
We found that callers of dma_get_seg_boundary mostly do an ALIGN
with page mask and then do a page shift to get number of pages:
    ALIGN(boundary + 1, 1 << shift) >> shift

However, the boundary might be as large as ULONG_MAX, which means
that a device has no specific boundary limit. So either "+ 1" or
passing it to ALIGN() would potentially overflow.

According to kernel defines:
    #define ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
    #define ALIGN(x, a)	ALIGN_MASK(x, (typeof(x))(a) - 1)

We can simplify the logic here into a helper function doing:
  ALIGN(boundary + 1, 1 << shift) >> shift
= ALIGN_MASK(b + 1, (1 << s) - 1) >> s
= {[b + 1 + (1 << s) - 1] & ~[(1 << s) - 1]} >> s
= [b + 1 + (1 << s) - 1] >> s
= [b + (1 << s)] >> s
= (b >> s) + 1

This patch introduces and applies dma_get_seg_boundary_nr_pages()
as an overflow-free helper for the dma_get_seg_boundary() callers
to get numbers of pages. It also takes care of the NULL dev case
for non-DMA API callers.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-03 18:12:15 +02:00
..
syscalls all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
asm-offsets.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
audit.c alpha: Enable system-call auditing support. 2014-01-31 09:21:55 -08:00
binfmt_loader.c exec: Remove recursion from search_binary_handler 2020-05-21 10:16:57 -05:00
bugs.c alpha: Implement CPU vulnerabilities sysfs functions. 2018-04-07 15:04:04 -07:00
console.c vgacon: Set VGA struct resource types 2017-12-18 23:07:43 -06:00
core_apecs.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
core_cia.c treewide: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
core_irongate.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
core_lca.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
core_marvel.c iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
core_mcpcia.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
core_polaris.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
core_t2.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
core_titan.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
core_tsunami.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
core_wildfire.c alpha: fix spelling mistake QSD_PORT_ACTUVE -> QSD_PORT_ACTIVE 2018-12-21 11:57:57 -05:00
entry.S alpha: unify the glue for sigreturn-like syscalls 2018-08-16 21:03:35 -04:00
err_common.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
err_ev6.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
err_ev7.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
err_impl.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
err_marvel.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
err_titan.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
es1888.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gct.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
io.c iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
irq_alpha.c alpha: Replace setup_irq() by request_irq() 2020-03-29 21:03:41 +02:00
irq_i8259.c alpha: Replace setup_irq() by request_irq() 2020-03-29 21:03:41 +02:00
irq_impl.h alpha: Replace setup_irq() by request_irq() 2020-03-29 21:03:41 +02:00
irq_pyxis.c alpha: Replace setup_irq() by request_irq() 2020-03-29 21:03:41 +02:00
irq_srm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
machvec_impl.h mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
Makefile alpha: Implement CPU vulnerabilities sysfs functions. 2018-04-07 15:04:04 -07:00
module.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
osf_sys.c alpha: remove unneeded semicolon in osf_sys.c 2020-06-12 17:43:17 -07:00
pc873xx.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pc873xx.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci_impl.h alpha: fix reboot on Avanti platform 2018-01-20 17:01:10 -08:00
pci_iommu.c dma-mapping: introduce dma_get_seg_boundary_nr_pages() 2020-09-03 18:12:15 +02:00
pci-noop.c treewide: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
pci-sysfs.c PCI: Add PCI_STD_NUM_BARS for the number of standard BARs 2019-10-14 10:22:26 -05:00
pci.c treewide: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
perf_event.c alpha: Use pr_warn instead of pr_warning 2019-10-18 10:26:32 +02:00
process.c arch: rename copy_thread_tls() back to copy_thread() 2020-07-04 23:41:37 +02:00
proto.h mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
ptrace.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
rtc.c alpha: rtc: simplify alpha_rtc_init 2018-12-21 11:57:57 -05:00
setup.c alpha: Fix build around srm_sysrq_reboot_op 2020-06-12 17:43:18 -07:00
signal.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
smc37c93x.c arch: mostly remove <asm/segment.h> 2019-04-23 21:51:40 +02:00
smc37c669.c arch: mostly remove <asm/segment.h> 2019-04-23 21:51:40 +02:00
smp.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
srm_env.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
srmcons.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
sys_alcor.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_cabriolet.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_dp264.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_eb64p.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_eiger.c alpha: remove unneeded semicolon in sys_eiger.c 2020-06-12 17:43:17 -07:00
sys_jensen.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_marvel.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_miata.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_mikasa.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_nautilus.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_noritake.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_rawhide.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_ruffian.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_rx164.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_sable.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_sio.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_sx164.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_takara.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_titan.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sys_wildfire.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
systbls.S alpha: generate uapi header and syscall table header files 2018-12-21 11:57:56 -05:00
time.c alpha: Replace setup_irq() by request_irq() 2020-03-29 21:03:41 +02:00
traps.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
vmlinux.lds.S alpha: Move EXCEPTION_TABLE to RO_DATA segment 2019-11-04 17:57:56 +01:00