[PATCH -V5 RESEND 06/21] swap: Support PMD swap mapping when splitting huge PMD

A huge PMD need to be split when zap a part of the PMD mapping etc. If the PMD mapping is a swap mapping, we need to split it too. This patch implemented the support for this. This is similar as splitting the PMD page mapping, except we need to decrease the PMD swap mapping count for the huge

[PATCH -V5 RESEND 06/21] swap: Support PMD swap mapping when splitting huge PMD

A huge PMD need to be split when zap a part of the PMD mapping etc. If the PMD mapping is a swap mapping, we need to split it too. This patch implemented the support for this. This is similar as splitting the PMD page mapping, except we need to decrease the PMD swap mapping count for the huge

[PATCH -V5 RESEND 06/21] swap: Support PMD swap mapping when splitting huge PMD

A huge PMD need to be split when zap a part of the PMD mapping etc. If the PMD mapping is a swap mapping, we need to split it too. This patch implemented the support for this. This is similar as splitting the PMD page mapping, except we need to decrease the PMD swap mapping count for the huge

[PATCH -V5 RESEND 06/21] swap: Support PMD swap mapping when splitting huge PMD

A huge PMD need to be split when zap a part of the PMD mapping etc. If the PMD mapping is a swap mapping, we need to split it too. This patch implemented the support for this. This is similar as splitting the PMD page mapping, except we need to decrease the PMD swap mapping count for the huge