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Mon, 01 May 2023 12:28:37 -0700 (PDT) Received: from fedora.hsd1.ca.comcast.net ([2601:644:937f:7f20::9a2c]) by smtp.googlemail.com with ESMTPSA id u8-20020a170902bf4800b0019c13d032d8sm18175622pls.253.2023.05.01.12.28.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 May 2023 12:28:36 -0700 (PDT) From: "Vishal Moola (Oracle)" To: Andrew Morton , Matthew Wilcox Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, "Vishal Moola (Oracle)" , David Hildenbrand , Claudio Imbrenda Subject: [PATCH v2 02/34] s390: Use _pt_s390_gaddr for gmap address tracking Date: Mon, 1 May 2023 12:27:57 -0700 Message-Id: <20230501192829.17086-3-vishal.moola@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230501192829.17086-1-vishal.moola@gmail.com> References: <20230501192829.17086-1-vishal.moola@gmail.com> MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Queue-Id: 5D42B40015 X-Rspamd-Server: rspam09 X-Stat-Signature: gi15w9p4gy9xhiii8c8ktiwkdw1rcqxr X-HE-Tag: 1682969318-525871 X-HE-Meta: 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 1uEYpuoI 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: s390 uses page->index to keep track of page tables for the guest address space. In an attempt to consolidate the usage of page fields in s390, replace _pt_pad_2 with _pt_s390_gaddr to replace page->index in gmap. This will help with the splitting of struct ptdesc from struct page, as well as allow s390 to use _pt_frag_refcount for fragmented page table tracking. Since page->_pt_s390_gaddr aliases with mapping, ensure its set to NULL before freeing the pages as well. This also reverts commit 7e25de77bc5ea ("s390/mm: use pmd_pgtable_page() helper in __gmap_segment_gaddr()") which had s390 use pmd_pgtable_page() to get a gmap page table, as pmd_pgtable_page() should be used for more generic process page tables. Signed-off-by: Vishal Moola (Oracle) --- arch/s390/mm/gmap.c | 56 +++++++++++++++++++++++++++------------- include/linux/mm_types.h | 2 +- 2 files changed, 39 insertions(+), 19 deletions(-) diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index dfe905c7bd8e..a9e8b1805894 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -70,7 +70,7 @@ static struct gmap *gmap_alloc(unsigned long limit) page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); if (!page) goto out_free; - page->index = 0; + page->_pt_s390_gaddr = 0; list_add(&page->lru, &gmap->crst_list); table = page_to_virt(page); crst_table_init(table, etype); @@ -187,16 +187,20 @@ static void gmap_free(struct gmap *gmap) if (!(gmap_is_shadow(gmap) && gmap->removed)) gmap_flush_tlb(gmap); /* Free all segment & region tables. */ - list_for_each_entry_safe(page, next, &gmap->crst_list, lru) + list_for_each_entry_safe(page, next, &gmap->crst_list, lru) { + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); + } gmap_radix_tree_free(&gmap->guest_to_host); gmap_radix_tree_free(&gmap->host_to_guest); /* Free additional data for a shadow gmap */ if (gmap_is_shadow(gmap)) { /* Free all page tables. */ - list_for_each_entry_safe(page, next, &gmap->pt_list, lru) + list_for_each_entry_safe(page, next, &gmap->pt_list, lru) { + page->_pt_s390_gaddr = 0; page_table_free_pgste(page); + } gmap_rmap_radix_tree_free(&gmap->host_to_rmap); /* Release reference to the parent */ gmap_put(gmap->parent); @@ -318,12 +322,14 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, list_add(&page->lru, &gmap->crst_list); *table = __pa(new) | _REGION_ENTRY_LENGTH | (*table & _REGION_ENTRY_TYPE_MASK); - page->index = gaddr; + page->_pt_s390_gaddr = gaddr; page = NULL; } spin_unlock(&gmap->guest_table_lock); - if (page) + if (page) { + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); + } return 0; } @@ -336,12 +342,14 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, static unsigned long __gmap_segment_gaddr(unsigned long *entry) { struct page *page; - unsigned long offset; + unsigned long offset, mask; offset = (unsigned long) entry / sizeof(unsigned long); offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE; - page = pmd_pgtable_page((pmd_t *) entry); - return page->index + offset; + mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); + page = virt_to_page((void *)((unsigned long) entry & mask)); + + return page->_pt_s390_gaddr + offset; } /** @@ -1351,6 +1359,7 @@ static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr) /* Free page table */ page = phys_to_page(pgt); list_del(&page->lru); + page->_pt_s390_gaddr = 0; page_table_free_pgste(page); } @@ -1379,6 +1388,7 @@ static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr, /* Free page table */ page = phys_to_page(pgt); list_del(&page->lru); + page->_pt_s390_gaddr = 0; page_table_free_pgste(page); } } @@ -1409,6 +1419,7 @@ static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr) /* Free segment table */ page = phys_to_page(sgt); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } @@ -1437,6 +1448,7 @@ static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr, /* Free segment table */ page = phys_to_page(sgt); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } } @@ -1467,6 +1479,7 @@ static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr) /* Free region 3 table */ page = phys_to_page(r3t); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } @@ -1495,6 +1508,7 @@ static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr, /* Free region 3 table */ page = phys_to_page(r3t); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } } @@ -1525,6 +1539,7 @@ static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr) /* Free region 2 table */ page = phys_to_page(r2t); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } @@ -1557,6 +1572,7 @@ static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr, /* Free region 2 table */ page = phys_to_page(r2t); list_del(&page->lru); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); } } @@ -1762,9 +1778,9 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; - page->index = r2t & _REGION_ENTRY_ORIGIN; + page->_pt_s390_gaddr = r2t & _REGION_ENTRY_ORIGIN; if (fake) - page->index |= GMAP_SHADOW_FAKE_TABLE; + page->_pt_s390_gaddr |= GMAP_SHADOW_FAKE_TABLE; s_r2t = page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); @@ -1814,6 +1830,7 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, return rc; out_free: spin_unlock(&sg->guest_table_lock); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); return rc; } @@ -1846,9 +1863,9 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; - page->index = r3t & _REGION_ENTRY_ORIGIN; + page->_pt_s390_gaddr = r3t & _REGION_ENTRY_ORIGIN; if (fake) - page->index |= GMAP_SHADOW_FAKE_TABLE; + page->_pt_s390_gaddr |= GMAP_SHADOW_FAKE_TABLE; s_r3t = page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); @@ -1898,6 +1915,7 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, return rc; out_free: spin_unlock(&sg->guest_table_lock); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); return rc; } @@ -1930,9 +1948,9 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; - page->index = sgt & _REGION_ENTRY_ORIGIN; + page->_pt_s390_gaddr = sgt & _REGION_ENTRY_ORIGIN; if (fake) - page->index |= GMAP_SHADOW_FAKE_TABLE; + page->_pt_s390_gaddr |= GMAP_SHADOW_FAKE_TABLE; s_sgt = page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); @@ -1982,6 +2000,7 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, return rc; out_free: spin_unlock(&sg->guest_table_lock); + page->_pt_s390_gaddr = 0; __free_pages(page, CRST_ALLOC_ORDER); return rc; } @@ -2014,9 +2033,9 @@ int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, if (table && !(*table & _SEGMENT_ENTRY_INVALID)) { /* Shadow page tables are full pages (pte+pgste) */ page = pfn_to_page(*table >> PAGE_SHIFT); - *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE; + *pgt = page->_pt_s390_gaddr & ~GMAP_SHADOW_FAKE_TABLE; *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT); - *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE); + *fake = !!(page->_pt_s390_gaddr & GMAP_SHADOW_FAKE_TABLE); rc = 0; } else { rc = -EAGAIN; @@ -2054,9 +2073,9 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, page = page_table_alloc_pgste(sg->mm); if (!page) return -ENOMEM; - page->index = pgt & _SEGMENT_ENTRY_ORIGIN; + page->_pt_s390_gaddr = pgt & _SEGMENT_ENTRY_ORIGIN; if (fake) - page->index |= GMAP_SHADOW_FAKE_TABLE; + page->_pt_s390_gaddr |= GMAP_SHADOW_FAKE_TABLE; s_pgt = page_to_phys(page); /* Install shadow page table */ spin_lock(&sg->guest_table_lock); @@ -2101,6 +2120,7 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, return rc; out_free: spin_unlock(&sg->guest_table_lock); + page->_pt_s390_gaddr = 0; page_table_free_pgste(page); return rc; diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 306a3d1a0fa6..6161fe1ae5b8 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -144,7 +144,7 @@ struct page { struct { /* Page table pages */ unsigned long _pt_pad_1; /* compound_head */ pgtable_t pmd_huge_pte; /* protected by page->ptl */ - unsigned long _pt_pad_2; /* mapping */ + unsigned long _pt_s390_gaddr; /* mapping */ union { struct mm_struct *pt_mm; /* x86 pgds only */ atomic_t pt_frag_refcount; /* powerpc */