diff options
author | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2020-05-19 23:01:26 +0200 |
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committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2020-05-19 23:37:01 +0200 |
commit | 2ae782ca839e0ee07de37122ddea362adff2e975 (patch) | |
tree | df6b1a190760f51465122ca4c13492d5ac5984c6 /mm/gup.c | |
parent | 0a8ab17689e628c84a666195bfc6ab85d11cf057 (diff) | |
parent | 0661b3d6cfd774e28a2e2ba90a3d87479e5c399b (diff) |
Merge tag 'v4.9.220' into 4.9-2.3.x-imx
This is the 4.9.220 stable release
Conflicts:
arch/arm/Kconfig.debug
arch/arm/boot/dts/imx7s.dtsi
arch/arm/mach-imx/common.h
arch/arm/mach-imx/cpuidle-imx6q.c
arch/arm/mach-imx/cpuidle-imx6sx.c
arch/arm/mach-imx/suspend-imx6.S
block/blk-core.c
drivers/crypto/caam/caamalg.c
drivers/crypto/mxs-dcp.c
drivers/dma/imx-sdma.c
drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
drivers/input/keyboard/imx_keypad.c
drivers/input/keyboard/snvs_pwrkey.c
drivers/mmc/host/sdhci.c
drivers/net/can/flexcan.c
drivers/net/ethernet/freescale/fec_main.c
drivers/net/phy/phy_device.c
drivers/net/wireless/ath/ath10k/pci.c
drivers/tty/serial/imx.c
drivers/usb/dwc3/gadget.c
drivers/usb/host/xhci.c
include/linux/blkdev.h
include/linux/cpu.h
include/linux/platform_data/dma-imx-sdma.h
kernel/cpu.c
net/wireless/util.c
sound/soc/fsl/Kconfig
sound/soc/fsl/fsl_esai.c
sound/soc/fsl/fsl_sai.c
sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'mm/gup.c')
-rw-r--r-- | mm/gup.c | 54 |
1 files changed, 37 insertions, 17 deletions
@@ -153,7 +153,10 @@ retry: } if (flags & FOLL_GET) { - get_page(page); + if (unlikely(!try_get_page(page))) { + page = ERR_PTR(-ENOMEM); + goto out; + } /* drop the pgmap reference now that we hold the page */ if (pgmap) { @@ -292,7 +295,10 @@ struct page *follow_page_mask(struct vm_area_struct *vma, if (pmd_trans_unstable(pmd)) ret = -EBUSY; } else { - get_page(page); + if (unlikely(!try_get_page(page))) { + spin_unlock(ptl); + return ERR_PTR(-ENOMEM); + } spin_unlock(ptl); lock_page(page); ret = split_huge_page(page); @@ -348,7 +354,10 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address, goto unmap; *page = pte_page(*pte); } - get_page(*page); + if (unlikely(!try_get_page(*page))) { + ret = -ENOMEM; + goto unmap; + } out: ret = 0; unmap: @@ -1231,6 +1240,20 @@ struct page *get_dump_page(unsigned long addr) */ #ifdef CONFIG_HAVE_GENERIC_RCU_GUP +/* + * Return the compund head page with ref appropriately incremented, + * or NULL if that failed. + */ +static inline struct page *try_get_compound_head(struct page *page, int refs) +{ + struct page *head = compound_head(page); + if (WARN_ON_ONCE(page_ref_count(head) < 0)) + return NULL; + if (unlikely(!page_cache_add_speculative(head, refs))) + return NULL; + return head; +} + #ifdef __HAVE_ARCH_PTE_SPECIAL static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, int write, struct page **pages, int *nr) @@ -1263,9 +1286,9 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, VM_BUG_ON(!pfn_valid(pte_pfn(pte))); page = pte_page(pte); - head = compound_head(page); - if (!page_cache_get_speculative(head)) + head = try_get_compound_head(page, 1); + if (!head) goto pte_unmap; if (unlikely(pte_val(pte) != pte_val(*ptep))) { @@ -1313,17 +1336,16 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr, return 0; refs = 0; - head = pmd_page(orig); - page = head + ((addr & ~PMD_MASK) >> PAGE_SHIFT); + page = pmd_page(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); do { - VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; (*nr)++; page++; refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + head = try_get_compound_head(pmd_page(orig), refs); + if (!head) { *nr -= refs; return 0; } @@ -1348,17 +1370,16 @@ static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr, return 0; refs = 0; - head = pud_page(orig); - page = head + ((addr & ~PUD_MASK) >> PAGE_SHIFT); + page = pud_page(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT); do { - VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; (*nr)++; page++; refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + head = try_get_compound_head(pud_page(orig), refs); + if (!head) { *nr -= refs; return 0; } @@ -1384,17 +1405,16 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr, return 0; refs = 0; - head = pgd_page(orig); - page = head + ((addr & ~PGDIR_MASK) >> PAGE_SHIFT); + page = pgd_page(orig) + ((addr & ~PGDIR_MASK) >> PAGE_SHIFT); do { - VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; (*nr)++; page++; refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + head = try_get_compound_head(pgd_page(orig), refs); + if (!head) { *nr -= refs; return 0; } |