From cc02e6e21aa5f2ac0defe8c15e5a9d024da6e73d Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Fri, 10 Jun 2022 11:04:36 +0200 Subject: [PATCH 1/9] s390/crash: add missing iterator advance in copy_oldmem_page() In case old memory was successfully copied the passed iterator should be advanced as well. Currently copy_oldmem_page() is always called with single-segment iterator. Should that ever change - copy_oldmem_user and copy_oldmem_kernel() functions would need a rework to deal with multi-segment iterators. Fixes: 5d8de293c224 ("vmcore: convert copy_oldmem_page() to take an iov_iter") Reviewed-by: Alexander Egorenkov Tested-by: Alexander Egorenkov Signed-off-by: Alexander Gordeev --- arch/s390/kernel/crash_dump.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index a2c1c55daec0..2534a31d2550 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -219,6 +219,11 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize, unsigned long src; int rc; + if (!(iter_is_iovec(iter) || iov_iter_is_kvec(iter))) + return -EINVAL; + /* Multi-segment iterators are not supported */ + if (iter->nr_segs > 1) + return -EINVAL; if (!csize) return 0; src = pfn_to_phys(pfn) + offset; @@ -228,6 +233,8 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize, rc = copy_oldmem_user(iter->iov->iov_base, src, csize); else rc = copy_oldmem_kernel(iter->kvec->iov_base, src, csize); + if (!rc) + iov_iter_advance(iter, csize); return rc; } From af2debd58bd769e38f538143f0d332e15d753396 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Thu, 9 Jun 2022 21:32:39 +0200 Subject: [PATCH 2/9] s390/crash: make copy_oldmem_page() return number of bytes copied Callback copy_oldmem_page() returns either error code or zero. Instead, it should return the error code or number of bytes copied. Fixes: df9694c7975f ("s390/dump: streamline oldmem copy functions") Reviewed-by: Alexander Egorenkov Tested-by: Alexander Egorenkov Signed-off-by: Alexander Gordeev --- arch/s390/kernel/crash_dump.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 2534a31d2550..28124d0fa1d5 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -233,9 +233,10 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize, rc = copy_oldmem_user(iter->iov->iov_base, src, csize); else rc = copy_oldmem_kernel(iter->kvec->iov_base, src, csize); - if (!rc) - iov_iter_advance(iter, csize); - return rc; + if (rc < 0) + return rc; + iov_iter_advance(iter, csize); + return csize; } /* From 7190d84966b34de3892cd4eb8698a2229ceb8d82 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Fri, 15 Jul 2022 06:43:32 +0200 Subject: [PATCH 3/9] s390/mm: remove unused tprot() function Since commit 461e0da7ddbb ("s390: remove broken hibernate / power management support") there are no users of tprot() left. Remove the function itself as well. Acked-by: Heiko Carstens Signed-off-by: Alexander Gordeev --- arch/s390/include/asm/mmu.h | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h index 82aae78e1315..bc254bce48fa 100644 --- a/arch/s390/include/asm/mmu.h +++ b/arch/s390/include/asm/mmu.h @@ -42,18 +42,4 @@ typedef struct { .context.pgtable_list = LIST_HEAD_INIT(name.context.pgtable_list), \ .context.gmap_list = LIST_HEAD_INIT(name.context.gmap_list), -static inline int tprot(unsigned long addr) -{ - int rc = -EFAULT; - - asm volatile( - " tprot 0(%1),0\n" - "0: ipm %0\n" - " srl %0,28\n" - "1:\n" - EX_TABLE(0b,1b) - : "+d" (rc) : "a" (addr) : "cc"); - return rc; -} - #endif From 86caa4b678956bc19567256dd8422f3978620897 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Fri, 15 Jul 2022 12:02:33 +0200 Subject: [PATCH 4/9] s390/crash: remove redundant panic() on save area allocation failure Make save_area_alloc() return classic NULL on allocation failure. The only caller smp_save_dump_cpus() does check the return value already and panics if NULL is returned. Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev --- arch/s390/kernel/crash_dump.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 28124d0fa1d5..117f13b3d153 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -63,7 +63,7 @@ struct save_area * __init save_area_alloc(bool is_boot_cpu) sa = memblock_alloc(sizeof(*sa), 8); if (!sa) - panic("Failed to allocate save area\n"); + return NULL; if (is_boot_cpu) list_add(&sa->list, &dump_save_areas); From f6749da17a34eb08c9665f072ce7c812ff68aad2 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Fri, 15 Jul 2022 12:59:33 +0200 Subject: [PATCH 5/9] s390/crash: fix incorrect number of bytes to copy to user space The number of bytes in a chunk is correctly calculated, but instead the total number of bytes is passed to copy_to_user_real() function. Reported-by: Matthew Wilcox Fixes: df9694c7975f ("s390/dump: streamline oldmem copy functions") Signed-off-by: Alexander Gordeev --- arch/s390/kernel/crash_dump.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 117f13b3d153..0efee5c49b1e 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -199,7 +199,7 @@ static int copy_oldmem_user(void __user *dst, unsigned long src, size_t count) } else { len = count; } - rc = copy_to_user_real(dst, src, count); + rc = copy_to_user_real(dst, src, len); if (rc) return rc; } From 9ffed254d938c9e99eb7761c7f739294c84e0367 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Tue, 19 Jul 2022 07:16:33 +0200 Subject: [PATCH 6/9] s390/zcore: fix race when reading from hardware system area Memory buffer used for reading out data from hardware system area is not protected against concurrent access. Reported-by: Matthew Wilcox Fixes: 411ed3225733 ("[S390] zfcpdump support.") Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/e68137f0f9a0d2558f37becc20af18e2939934f6.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev --- drivers/s390/char/zcore.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c index 516783ba950f..92b32ce645b9 100644 --- a/drivers/s390/char/zcore.c +++ b/drivers/s390/char/zcore.c @@ -50,6 +50,7 @@ static struct dentry *zcore_reipl_file; static struct dentry *zcore_hsa_file; static struct ipl_parameter_block *zcore_ipl_block; +static DEFINE_MUTEX(hsa_buf_mutex); static char hsa_buf[PAGE_SIZE] __aligned(PAGE_SIZE); /* @@ -66,19 +67,24 @@ int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count) if (!hsa_available) return -ENODATA; + mutex_lock(&hsa_buf_mutex); while (count) { if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) { TRACE("sclp_sdias_copy() failed\n"); + mutex_unlock(&hsa_buf_mutex); return -EIO; } offset = src % PAGE_SIZE; bytes = min(PAGE_SIZE - offset, count); - if (copy_to_user(dest, hsa_buf + offset, bytes)) + if (copy_to_user(dest, hsa_buf + offset, bytes)) { + mutex_unlock(&hsa_buf_mutex); return -EFAULT; + } src += bytes; dest += bytes; count -= bytes; } + mutex_unlock(&hsa_buf_mutex); return 0; } @@ -96,9 +102,11 @@ int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count) if (!hsa_available) return -ENODATA; + mutex_lock(&hsa_buf_mutex); while (count) { if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) { TRACE("sclp_sdias_copy() failed\n"); + mutex_unlock(&hsa_buf_mutex); return -EIO; } offset = src % PAGE_SIZE; @@ -108,6 +116,7 @@ int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count) dest += bytes; count -= bytes; } + mutex_unlock(&hsa_buf_mutex); return 0; } From d6da67378198e4caa37404f87851659553b936b9 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Tue, 19 Jul 2022 07:16:34 +0200 Subject: [PATCH 7/9] s390/crash: move copy_to_user_real() to crash_dump.c Function copy_to_user_real() does not really belong to maccess.c. It is only used for copying oldmem to user space, so let's move it to the friends. Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/e8de968d40202d87caa09aef12e9c67ec23a1c1a.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev --- arch/s390/include/asm/uaccess.h | 1 - arch/s390/kernel/crash_dump.c | 26 ++++++++++++++++++++++++++ arch/s390/mm/maccess.c | 26 -------------------------- 3 files changed, 26 insertions(+), 27 deletions(-) diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index f4511e21d646..2a067315fe59 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -285,7 +285,6 @@ static inline unsigned long __must_check clear_user(void __user *to, unsigned lo return __clear_user(to, n); } -int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count); void *s390_kernel_write(void *dst, const void *src, size_t size); int __noreturn __put_kernel_bad(void); diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 0efee5c49b1e..8d7332d4444c 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -173,6 +173,32 @@ int copy_oldmem_kernel(void *dst, unsigned long src, size_t count) return 0; } +/* + * Copy memory from kernel (real) to user (virtual) + */ +static int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count) +{ + int offs = 0, size, rc; + char *buf; + + buf = (char *)__get_free_page(GFP_KERNEL); + if (!buf) + return -ENOMEM; + rc = -EFAULT; + while (offs < count) { + size = min(PAGE_SIZE, count - offs); + if (memcpy_real(buf, src + offs, size)) + goto out; + if (copy_to_user(dest + offs, buf, size)) + goto out; + offs += size; + } + rc = 0; +out: + free_page((unsigned long)buf); + return rc; +} + /* * Copy memory of the old, dumped system to a user space virtual address */ diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c index 421efa46946b..d6d84e02f35a 100644 --- a/arch/s390/mm/maccess.c +++ b/arch/s390/mm/maccess.c @@ -171,32 +171,6 @@ void memcpy_absolute(void *dest, void *src, size_t count) arch_local_irq_restore(flags); } -/* - * Copy memory from kernel (real) to user (virtual) - */ -int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count) -{ - int offs = 0, size, rc; - char *buf; - - buf = (char *) __get_free_page(GFP_KERNEL); - if (!buf) - return -ENOMEM; - rc = -EFAULT; - while (offs < count) { - size = min(PAGE_SIZE, count - offs); - if (memcpy_real(buf, src + offs, size)) - goto out; - if (copy_to_user(dest + offs, buf, size)) - goto out; - offs += size; - } - rc = 0; -out: - free_page((unsigned long) buf); - return rc; -} - /* * Check if physical address is within prefix or zero page */ From 6d2e5a4a13da2e91a46a37cd00d23dba8613ad7b Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Tue, 19 Jul 2022 07:16:35 +0200 Subject: [PATCH 8/9] s390/crash: use static swap buffer for copy_to_user_real() Currently a temporary page-size buffer is allocated for copying oldmem to user space. That limits copy_to_user_real() operation only to stages when virtual memory is available and still makes it possible to fail while the system is being dumped. Instead of reallocating single page on each copy_oldmem_page() iteration use a statically allocated buffer. This also paves the way for a further memcpy_real() rework where no swap buffer is needed altogether. Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/334ed359680c4d45dd32feb104909f610312ef0f.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev --- arch/s390/kernel/crash_dump.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 8d7332d4444c..1662f1d81abe 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -53,6 +53,8 @@ struct save_area { }; static LIST_HEAD(dump_save_areas); +static DEFINE_MUTEX(memcpy_real_mutex); +static char memcpy_real_buf[PAGE_SIZE]; /* * Allocate a save area @@ -178,25 +180,21 @@ int copy_oldmem_kernel(void *dst, unsigned long src, size_t count) */ static int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count) { - int offs = 0, size, rc; - char *buf; + unsigned long offs = 0, size; - buf = (char *)__get_free_page(GFP_KERNEL); - if (!buf) - return -ENOMEM; - rc = -EFAULT; + mutex_lock(&memcpy_real_mutex); while (offs < count) { size = min(PAGE_SIZE, count - offs); - if (memcpy_real(buf, src + offs, size)) - goto out; - if (copy_to_user(dest + offs, buf, size)) - goto out; + if (memcpy_real(memcpy_real_buf, src + offs, size)) + break; + if (copy_to_user(dest + offs, memcpy_real_buf, size)) + break; offs += size; } - rc = 0; -out: - free_page((unsigned long)buf); - return rc; + mutex_unlock(&memcpy_real_mutex); + if (offs < count) + return -EFAULT; + return 0; } /* From ebbc9570169147740aa39aee1d61b4cc5a631644 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Tue, 19 Jul 2022 07:16:36 +0200 Subject: [PATCH 9/9] s390/crash: support multi-segment iterators Make it possible to handle not only single-, but also multi- segment iterators in copy_oldmem_iter() callback. Change the semantics of called functions to match the iterator model - instead of an error code the exact number of bytes copied is returned. The swap page used to copy data to user space is adopted for kernel space too. That does not bring any performance impact. Suggested-by: Matthew Wilcox Fixes: cc02e6e21aa5 ("s390/crash: add missing iterator advance in copy_oldmem_page()") Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/5af6da3a0bffe48a90b0b7139ecf6a818b2d18e8.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev --- arch/s390/include/asm/os_info.h | 17 ++++- arch/s390/include/asm/sclp.h | 4 +- arch/s390/kernel/crash_dump.c | 128 ++++++-------------------------- drivers/s390/char/zcore.c | 58 ++++++--------- 4 files changed, 63 insertions(+), 144 deletions(-) diff --git a/arch/s390/include/asm/os_info.h b/arch/s390/include/asm/os_info.h index 147a8d547ef9..85248d8fee0c 100644 --- a/arch/s390/include/asm/os_info.h +++ b/arch/s390/include/asm/os_info.h @@ -8,6 +8,8 @@ #ifndef _ASM_S390_OS_INFO_H #define _ASM_S390_OS_INFO_H +#include + #define OS_INFO_VERSION_MAJOR 1 #define OS_INFO_VERSION_MINOR 1 #define OS_INFO_MAGIC 0x4f53494e464f535aULL /* OSINFOSZ */ @@ -39,7 +41,20 @@ u32 os_info_csum(struct os_info *os_info); #ifdef CONFIG_CRASH_DUMP void *os_info_old_entry(int nr, unsigned long *size); -int copy_oldmem_kernel(void *dst, unsigned long src, size_t count); +size_t copy_oldmem_iter(struct iov_iter *iter, unsigned long src, size_t count); + +static inline int copy_oldmem_kernel(void *dst, unsigned long src, size_t count) +{ + struct iov_iter iter; + struct kvec kvec; + + kvec.iov_base = dst; + kvec.iov_len = count; + iov_iter_kvec(&iter, WRITE, &kvec, 1, count); + if (copy_oldmem_iter(&iter, src, count) < count) + return -EFAULT; + return 0; +} #else static inline void *os_info_old_entry(int nr, unsigned long *size) { diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h index 236b34b75ddb..24ee532fab84 100644 --- a/arch/s390/include/asm/sclp.h +++ b/arch/s390/include/asm/sclp.h @@ -17,6 +17,7 @@ #define EXT_SCCB_READ_CPU (3 * PAGE_SIZE) #ifndef __ASSEMBLY__ +#include #include #include @@ -142,8 +143,7 @@ int sclp_pci_deconfigure(u32 fid); int sclp_ap_configure(u32 apid); int sclp_ap_deconfigure(u32 apid); int sclp_pci_report(struct zpci_report_error_header *report, u32 fh, u32 fid); -int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count); -int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count); +size_t memcpy_hsa_iter(struct iov_iter *iter, unsigned long src, size_t count); void sclp_ocf_cpc_name_copy(char *dst); static inline int sclp_get_core_info(struct sclp_core_info *info, int early) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 1662f1d81abe..bad8f47fc5d6 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -116,102 +116,35 @@ void __init save_area_add_vxrs(struct save_area *sa, __vector128 *vxrs) memcpy(sa->vxrs_high, vxrs + 16, 16 * sizeof(__vector128)); } -/* - * Return physical address for virtual address - */ -static inline void *load_real_addr(void *addr) +static size_t copy_to_iter_real(struct iov_iter *iter, unsigned long src, size_t count) { - unsigned long real_addr; - - asm volatile( - " lra %0,0(%1)\n" - " jz 0f\n" - " la %0,0\n" - "0:" - : "=a" (real_addr) : "a" (addr) : "cc"); - return (void *)real_addr; -} - -/* - * Copy memory of the old, dumped system to a kernel space virtual address - */ -int copy_oldmem_kernel(void *dst, unsigned long src, size_t count) -{ - unsigned long len; - void *ra; - int rc; - - while (count) { - if (!oldmem_data.start && src < sclp.hsa_size) { - /* Copy from zfcp/nvme dump HSA area */ - len = min(count, sclp.hsa_size - src); - rc = memcpy_hsa_kernel(dst, src, len); - if (rc) - return rc; - } else { - /* Check for swapped kdump oldmem areas */ - if (oldmem_data.start && src - oldmem_data.start < oldmem_data.size) { - src -= oldmem_data.start; - len = min(count, oldmem_data.size - src); - } else if (oldmem_data.start && src < oldmem_data.size) { - len = min(count, oldmem_data.size - src); - src += oldmem_data.start; - } else { - len = count; - } - if (is_vmalloc_or_module_addr(dst)) { - ra = load_real_addr(dst); - len = min(PAGE_SIZE - offset_in_page(ra), len); - } else { - ra = dst; - } - if (memcpy_real(ra, src, len)) - return -EFAULT; - } - dst += len; - src += len; - count -= len; - } - return 0; -} - -/* - * Copy memory from kernel (real) to user (virtual) - */ -static int copy_to_user_real(void __user *dest, unsigned long src, unsigned long count) -{ - unsigned long offs = 0, size; + size_t len, copied, res = 0; mutex_lock(&memcpy_real_mutex); - while (offs < count) { - size = min(PAGE_SIZE, count - offs); - if (memcpy_real(memcpy_real_buf, src + offs, size)) + while (count) { + len = min(PAGE_SIZE, count); + if (memcpy_real(memcpy_real_buf, src, len)) break; - if (copy_to_user(dest + offs, memcpy_real_buf, size)) + copied = copy_to_iter(memcpy_real_buf, len, iter); + count -= copied; + src += copied; + res += copied; + if (copied < len) break; - offs += size; } mutex_unlock(&memcpy_real_mutex); - if (offs < count) - return -EFAULT; - return 0; + return res; } -/* - * Copy memory of the old, dumped system to a user space virtual address - */ -static int copy_oldmem_user(void __user *dst, unsigned long src, size_t count) +size_t copy_oldmem_iter(struct iov_iter *iter, unsigned long src, size_t count) { - unsigned long len; - int rc; + size_t len, copied, res = 0; while (count) { if (!oldmem_data.start && src < sclp.hsa_size) { /* Copy from zfcp/nvme dump HSA area */ len = min(count, sclp.hsa_size - src); - rc = memcpy_hsa_user(dst, src, len); - if (rc) - return rc; + copied = memcpy_hsa_iter(iter, src, len); } else { /* Check for swapped kdump oldmem areas */ if (oldmem_data.start && src - oldmem_data.start < oldmem_data.size) { @@ -223,15 +156,15 @@ static int copy_oldmem_user(void __user *dst, unsigned long src, size_t count) } else { len = count; } - rc = copy_to_user_real(dst, src, len); - if (rc) - return rc; + copied = copy_to_iter_real(iter, src, len); } - dst += len; - src += len; - count -= len; + count -= copied; + src += copied; + res += copied; + if (copied < len) + break; } - return 0; + return res; } /* @@ -241,26 +174,9 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize, unsigned long offset) { unsigned long src; - int rc; - if (!(iter_is_iovec(iter) || iov_iter_is_kvec(iter))) - return -EINVAL; - /* Multi-segment iterators are not supported */ - if (iter->nr_segs > 1) - return -EINVAL; - if (!csize) - return 0; src = pfn_to_phys(pfn) + offset; - - /* XXX: pass the iov_iter down to a common function */ - if (iter_is_iovec(iter)) - rc = copy_oldmem_user(iter->iov->iov_base, src, csize); - else - rc = copy_oldmem_kernel(iter->kvec->iov_base, src, csize); - if (rc < 0) - return rc; - iov_iter_advance(iter, csize); - return csize; + return copy_oldmem_iter(iter, src, csize); } /* diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c index 92b32ce645b9..f6da215ccf9f 100644 --- a/drivers/s390/char/zcore.c +++ b/drivers/s390/char/zcore.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -54,38 +55,37 @@ static DEFINE_MUTEX(hsa_buf_mutex); static char hsa_buf[PAGE_SIZE] __aligned(PAGE_SIZE); /* - * Copy memory from HSA to user memory (not reentrant): + * Copy memory from HSA to iterator (not reentrant): * - * @dest: User buffer where memory should be copied to + * @iter: Iterator where memory should be copied to * @src: Start address within HSA where data should be copied * @count: Size of buffer, which should be copied */ -int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count) +size_t memcpy_hsa_iter(struct iov_iter *iter, unsigned long src, size_t count) { - unsigned long offset, bytes; + size_t bytes, copied, res = 0; + unsigned long offset; if (!hsa_available) - return -ENODATA; + return 0; mutex_lock(&hsa_buf_mutex); while (count) { if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) { TRACE("sclp_sdias_copy() failed\n"); - mutex_unlock(&hsa_buf_mutex); - return -EIO; + break; } offset = src % PAGE_SIZE; bytes = min(PAGE_SIZE - offset, count); - if (copy_to_user(dest, hsa_buf + offset, bytes)) { - mutex_unlock(&hsa_buf_mutex); - return -EFAULT; - } - src += bytes; - dest += bytes; - count -= bytes; + copied = copy_to_iter(hsa_buf + offset, bytes, iter); + count -= copied; + src += copied; + res += copied; + if (copied < bytes) + break; } mutex_unlock(&hsa_buf_mutex); - return 0; + return res; } /* @@ -95,28 +95,16 @@ int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count) * @src: Start address within HSA where data should be copied * @count: Size of buffer, which should be copied */ -int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count) +static inline int memcpy_hsa_kernel(void *dst, unsigned long src, size_t count) { - unsigned long offset, bytes; + struct iov_iter iter; + struct kvec kvec; - if (!hsa_available) - return -ENODATA; - - mutex_lock(&hsa_buf_mutex); - while (count) { - if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) { - TRACE("sclp_sdias_copy() failed\n"); - mutex_unlock(&hsa_buf_mutex); - return -EIO; - } - offset = src % PAGE_SIZE; - bytes = min(PAGE_SIZE - offset, count); - memcpy(dest, hsa_buf + offset, bytes); - src += bytes; - dest += bytes; - count -= bytes; - } - mutex_unlock(&hsa_buf_mutex); + kvec.iov_base = dst; + kvec.iov_len = count; + iov_iter_kvec(&iter, WRITE, &kvec, 1, count); + if (memcpy_hsa_iter(&iter, src, count) < count) + return -EIO; return 0; }